OBSERVATIONS
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The assessment was conducted and the report prepared under a CAP grant funded by the Institute for Museum and Library Services and administered by Heritage Preservation, Inc. Click here for more information on the CAP grant program. Since this report was originally prepared several years ago, some of the addresses and telephone numbers referred to in the footnotes may be out of date. CONSERVATION ASSESSMENT 13 OAK STREET 1997 Report (21 pages) Consolidated field notes (19 pages) Nomenclature and sketch floor plans (3 pages) Appendices Prepared for the Town Historical Museum This report summarizes the findings, conclusions, and recommendations of a conservation assessment visit made to the Town Historical Museum building in 1997. It is based on conditions observed at that time, using non-invasive techniques, and on information supplied by Museum personnel. Due care was used in making these observations, and all conclusions are based on the assessor's professional experience as an architect specializing in historic preservation and history museum buildings, but no warranty can be made as to their completeness or correctness. This report should be construed as an initial step in the process of determining and meeting the building's conservation needs. An edited copy of the field notes taken during that visit is included as an appendix, and contains information and recommendations about the building that were not feasible to include in the body of this report. In referring to building elements, this report will use the names shown on the sketch floor plans which are included as an appendix. Like many small institutions, the Town Historical Museum operates with scant financial resources; its annual budget is only about two thousand dollars. The amount that the Museum has been able to accomplish under this brutal constraint is a tribute to the very hard and excellent work that everyone connected with the Museum has been doing. In many ways, this report may appear unfair to the Museum's diligent efforts--the need to boil a huge amount of information down into a reasonably compact form can lead to a bluntness that gives short shrift to the many positive aspects of this institution and the dedication of those who manage it. Too, the report's emphasis is on the many problems and pathologies needing attention, rather than the "unremarkable" situations that don't. The intent was not to launch an overwhelming broadside of criticism, but rather to outline in reasonable detail the issues that we believe are important to the ongoing conservation, restoration, and preservation of the Museum's building. Our task was complicated by the imminent possibility of a move to space in the soon-to-be-expanded Public Library, and the ambiguous situation into which it casts the Museum building. Even assuming that this change will come to pass, however, the Museum will remain at least two years more in its present location. Accordingly, we have opted to prepare this report as though the Museum would remain in the Oak Street building for the foreseeable future, but at the same time to attempt to discuss important issues specific to a move to new (and as yet unconstructed) space. This report is intended to complement, and should be read in conjunction with, the collections assessment report prepared by [_______], Collection Assessor. Built around 1900, the Museum's building appears to survive with most of its original work intact. It stands on a generally open site, sloping down from east to west, and fronting on Oak Street to the north. In form the structure is a simple gable-on-hip-roofed one and one-half story wooden structure with a projecting pavilion and entrance porch to the north. Construction is wood-frame throughout. The basement perimeter wall is rubble masonry below grade and brick above. Interior finishes are primarily plaster walls and ceilings above beaded matched board wainscots. Floors and trim are wood. The basement floor is concrete. The heating system was removed some years ago. II. SUMMARY OF FINDINGS, CONCERNS, AND RECOMMENDATIONS The building on Oak Street occupied by the Town Historical Museum was used as a schoolhouse from its construction around 1900 until 1942, when it became the Museum's home. As a museum structure, however, it is problematical. On the one hand, as an historically significant artifact of Town's past it is an appropriate and wonderful home for Town's "memory." On the other, its construction and the present lack of climate control prevent establishing and maintaining an interior environment that will ensure the long-term preservation of the collections housed in it.* The building has also been undermaintained for many years--the result of a chronic lack of adequate funds with which to take care of it--with the consequence that a great deal of remedial work is required, ranging from removing the blue wrapper and repairing the chimney to repairing water damage inside the building, planning for replacing the roofs, and providing sanitary and convenient toilet facilities. Most of this work--including providing a heating plant--will be required whether or not the Museum continues to occupy the place.
The Museum is presently on the verge of having the opportunity to move to more secure and climate-controlled space in the newly enlarged town library. So long as adequate measures are taken to deal with the risk of dampness due to the proposed exhibit space's location below grade, this space appears to offer a substantial improvement in conditions for the Museum and its collections, although we are concerned about the effect of separating the gallery and work areas as widely as is proposed. Whether or not the Museum moves to new space, it will continue to occupy the Oak Street building for the next couple of years, making it important to undertake at least the most basic and most critical work as soon as possible. The following is a summary of the major issues raised in the course of this conservation assessment: A. General concerns - Resource management: The Museum's resources for caring for its collections and building are meager, and visitation is small. There is an urgent need to develop over time ways to expand both the Museum's resources and its visitation. - Effects of the proposed move to the Public Library: The imminent possibility of a move to new space in the Library has sidetracked most activity directed toward the ongoing care and conservation of the building. There is an urgent need to develop both an interim strategy for dealing with the building, assuming that the Museum will move, and a longer-term strategy to cover the contingency that it may not. - Building records/ archive: There is presently no systematic record of the history of the building and events affecting it. There is an urgent need to develop such an archive as a fundamental planning and management document. - Periodic maintenance plan: There is presently no written plan for the periodic maintenance of the building. Particularly where the Museum and the Town are both involved in its maintenance, there is an urgent need for such a document. - Restoration/conservation plan: Presently there is no comprehensive, prioritized list of needed restoration and conservation work. Particularly since much of this work will have to go through the Town's capital budget process, there is an urgent need to develop such a plan. - Role of the building: It is not presently clear whether the building is simply a container for the Museum's collections, or an exhibit in its own right. There is a serious need to determine what the building represents, as a guide for planning for ongoing management, maintenance, and conservation. B. Exterior concerns - Chimney and flashings: The existing blue wrapper covering the chimney was placed there in response to an emergency several years ago. It is urgent that it be removed and the chimney and associated flashings be repaired, whether or not the Museum remains here. - Roof and flashings: The roofing does not appear presently to be in crisis, but both asphalt and metal roofs appear to be near the ends of their useful lives. There is a serious-to-urgent need to replace them within the next few years. - Drainage: Appropriate site drainage is a key factor in minimizing the amount of moisture entering a rubble-stone basement such as the Museum's. There is a serious-to-urgent need to modify the existing surface drainage, particularly at the ends of the front entrance pavilion. - Exterior envelope: Overall, the exterior walls and siding appear to be in good condition. The exception lies on the south side, where movement of the wall against the roof overhang has resulted in a serious need to undertake destructive investigation, followed by appropriate repairs. - Site plantings: Vegetation to the south of the building is encroaching on it. There is a serious need to prune and remove these trees and shrubs. C. Interior concerns - Toilets: That the Museum's staff puts up with the existing toilet facilities is yet further testimony to their great dedication. There is an urgent need to provide better. - Insect infestation: We noted only one small area in the basement with obvious signs of insect infestation. There is a serious-to-urgent need to treat and monitor this area so that the infestation, if active, will not spread. - Interior environment--basement: Dampness in the basement is a serious-to-urgent concern. The existing plastic sheeting on the floor is an excellent step in the right direction, as would be increased ventilation obtained by selectively opening basement windows. - Water-related damage: Repair of water damage to second-story finishes and the basement stairs is a serious-to-urgent matter. In particular, the basement stair stringers are rotting and becoming liable to collapse. - Access: The Museum's building is not accessible under the provisions of either State or Federal law. There is a serious-to-urgent need for a compliance survey and plan, to be followed by appropriate modifications to render the building more accessible to disabled people. - Interior environment--upper stories: Interior conditions are presently subject to wide daily swings in temperature and humidity. There is a serious need to develop and implement measures to improve ventilation and to stabilize day-to-day environmental conditions. - Interior environment--off-season: During the off season when the building is not used, condensation and wide daily fluctuations in humidity are problems. There is a serious need to implement measures to mitigate these conditions. - Electrical system and lighting: The existing electrical system and lighting are totally inadequate. There is an urgent need to upgrade them; in view of the Museum's other needs, we have downgraded it to serious. - Interior finishes: Finish condition varies from good to failing. The need throughout the building, over time, to conserve, clean, and repair these finishes is a cause for serious concern. - Window sash: The condition of sash and their finish is a cause for serious concern. Sash appear structurally sound, but weathered, primarily due to wintertime condensation. Finishes are failing. Window conservation can successfully be undertaken on a unit-by-unit basis over an extended period. D. Concerns related to the proposed new museum space at the Public Library - Separation of museum space: The separation between the proposed gallery and the upper-story storage and work space represents a cause for concern. - Location of museum space: The new exhibit space is partly below grade, making it vulnerable to vapor and water entry. Ensuring that appropriate measures are taken to guard against this problem is a cause for concern. - Loss of autonomy: The fact that the Museum will no longer be constrained only by its own resources, but will also be affected by the Library's actions and policies which may not always be in the Museum's best interest represents a cause for concern. III. FINDINGS, CONCERNS, AND RECOMMENDATIONS A. General concerns - Resource management: For an organization with an annual budget of approximately two thousand dollars, the Museum has done an impressive job of maintaining the building. With the exception of the chimney and immediate environs, the structure's exterior presents in good condition. Inside the building, the primary spaces appear quite well cared for, although it is clear that resources have had to be directed where they would make the greatest effect. A building of this size has a replacement value on the order of three hundred thousand dollars. A rough rule of thumb says that over time the annual cost of maintaining a building in standard condition* will average about five percent of its replacement value. This means that in a more perfect world up to fifteen thousand dollars per year would have been devoted to the Museum building. Even two-thirds of this amount--more consistent with the realities of an "adequately funded" institution--would have been sufficient to arrest most of the deterioration that is now evident, and to underwrite retention and upgrading of the heating system and other improvements.
Unfortunately, funding at that level has simply not been possible, with the consequence that needed work has had to be postponed, and deteriorated conditions have had to be left uncorrected. The cumulative result is that, as this report will show, the building now requires major repair and conservation work to return it to standard condition. The sources of funding to support such a program over time is an urgent and difficult question. The needs of the present Town Historical Museum building exceed the Museum's and Town's ability to meet in the short term. This situation places a premium on long-term planning and making the strongest possible case for support from the Museum's present constituency, from the Town, and from outside funding sources. A critical part of this enterprise will include developing the periodic maintenance and conservation/restoration plans mentioned elsewhere in this report, to obtain a comprehensive picture of the work that will be required, to coordinate with the Town's ongoing budgetary process, and to use in rallying new financial support. - Effects of the proposed move to the Public Library: The looming possibility of a move to new space at the Library, combined with the Museum's tight funding, have sidetracked most activity directed toward the ongoing care and conservation of the present building. That is a dangerous, if understandable, course of action. Assuming that the Town votes to proceed with construction documents and bidding at a meeting this September, significant time will still elapse before the new space is ready. Construction will not start until the spring of 1999 at the earliest, and even that is not certain.* Construction will require between six months and a year, with the result that the earliest likely date for a move to new space is about two years from now. To assume otherwise is simply imprudent. During that interim, the Museum will remain in its present quarters, whose needs and deficiencies will not spontaneously abate.
Until the Town has irrevocably committed to an expanded library, including space for the Museum, the Museum should attend to as many smaller projects as possible to improve the environment in which its collections presently are kept, and should work vigorously to convince the Town immediately to repair the chimney and associated flashings to the point where the blue wrapper can safely be removed. At the same time, we recommend that the Museum develop two ongoing strategies for its own actions: The first to ensure that space in the renovated library is acceptable and committed to Museum use for a reasonable time, and the second to address the contingency that the Library may not pass Town Meeting this fall. In that case, the Museum is likely remain at Oak Street for some time, making immediately addressing the building's major conservation needs a critical issue.
- Building records/ archive: A systematic record of the building's history and the events happening to it is an essential resource for the ongoing stewardship of the Town Historical Museum building. The building archive's purpose is twofold--to serve as a repository of a particular part of "the History of the Historical Museum," and to serve as a fundamental resource for the management and maintenance of the building. At present there are no systematic building records and no building archive. This is a serious omission; a formal building archive should be started immediately. At the minimum, the building archive should contain a contemporary record of all maintenance (routine and extraordinary), conservation, construction, demolition, restoration, and unusual occurrences (leaks, building failures, break-ins, visitor accidents, etc.), using logs, specifications, notes, sketches, photographs, invoices, and whatever other documentation may be appropriate. In addition, it is desirable that the archive contain as much historical information about the building as can be, including its original form, configuration, and finishes, and subsequent events and modifications. Filling in the many gaps in the historical record will be an important ongoing research activity. - Periodic maintenance plan: Periodic maintenance incorporates everything from daily and seasonal opening and closing routines, to housekeeping, to repainting and reroofing. A periodic maintenance and ongoing conservation plan, properly prepared and kept up-to-date, provides an orderly structure for property maintenance, helps financial planning to meet building needs, and ensures continuity by moving long-term maintenance needs and scheduling from an individual's mind into the institutional memory, where it will be accessible when needed. When resources are scarce and multiple organizations are involved, as clearly is the case at the Town Historical Museum, the existence of a carefully-prepared plan helps ensure that resources will be used to yield the most benefit, and that major items will be budgeted for sufficiently in advance of need to avoid disasters like the recent roof leak. Where the Museum does not own its building, the periodic maintenance plan serves also as a tool for alerting the building's owners--the Town--to its ongoing needs and for promoting awareness of the need for action to meet them. We recommend immediately starting to prepare a such a plan.
- Restoration/conservation plan: In addition to a periodic maintenance plan to guide the day-to-day care of the Museum's building, a restoration and conservation plan is needed to provide for the major repairs and other conservation and restoration work the building presently needs. Although the building conservation plan can be made part of an ongoing periodic maintenance plan, in the case of the Town Historical Museum we believe it is preferable to keep it separate: Much of the conservation and restoration work the Museum needs is larger-scaled and more expensive than all but the most major periodic-maintenance items (repainting and re-roofing). It represents capital expenses, while periodic maintenance typically represents operating expenses. In a situation where the Town Historical Museum building is municipally owned, this distinction is significant to the Town's budgeting and money-raising process.
As with a periodic maintenance plan, a conservation and maintenance plan provides a necessary orderly structure to the process and helps ensure continuity by committing the building's conservation and restoration needs to the institutional memory. Unlike periodic maintenance, much of which can be handled independently by the Museum, the plan for conservation and restoration will require working closely with the appropriate Town bodies in order to succeed. - Role of the building: The role of an historical organization's building is by nature ambiguous and internally contradictory: Is it merely a container for the Museum's collections, or is it an exhibit in its own right--the largest and most intractable object in the collection? This role may change over time; the Museum's building historically has been viewed primarily as a container, but it has gained willy-nilly aspects of an exhibit in its own right, particularly in conjunction with its use as a schoolhouse from its construction into the early nineteen-forties. Assuming that the Museum remains in the Oak Street building and does not move to new space in the Library, a critical issue will be to decide what this building represents: Is it a vessel to contain the Museum which just happens to be a well-preserved turn-of-the-century schoolhouse, or is it an exhibit in its own right? How can the building contribute to the Museum's programs? How can necessary modifications be made without unduly compromising its integrity? To the extent that the building is worthy of preservation and interpretation in its own right--which we believe to be the case--nominating it to the National Register of Historic Places, followed by seeking status as a Totally Preserved Building under the Massachusetts State Building Code may be useful. These steps would ease some code-compliance issues, and would provide access to the minute amount of grant money that is presently available. A clear and well-considered answer to the question of the building's role will be an essential component of the context in which to resolve the issues that this report discusses, and an anchor to windward when hard decisions have to be made about specific work. Regardless of the building's role, it is important to establish and maintain a building archive, as recommended earlier in this report. The importance of documenting all changes made to any building occupied by a curatorial organization, regardless of its role, should go without saying. The ramifications of the building's role begin at the point where that role (container or exhibit) affects what work is undertaken and how it is executed. Depending on the building's purpose, very different approaches (with differing costs) may be required to address the same physical concern. B. Exterior concerns The exterior of the Museum building appears generally to be in good condition, particularly in light of the resources that have been available for its maintenance. That said, there exist several areas of concern: - Chimney and flashings: As is apparent to the most casual visitor to the building, the chimney has a serious problem. It appears that the leak was caused by a combination of a problem with the chimney itself and failure of the flashing at its base. The bright blue wrapper appears to have been an effective immediate "first-aid" solution to the major leaks that had occurred, but it was appropriate for at most one season. Several years have elapsed with no subsequent action. The chimney needs to be inspected by a skilled preservation mason, following which the necessary masonry and flashing repairs should be made. Simply buttering the base of the chimney with roofing mastic ("black goo") will solve nothing and will, in the long run, exacerbate the problem. The existing flashing and counterflashing should be replaced with new copper. The stack should be repointed,* using a relatively soft (weak) mortar in order not to risk long-term damage to the brick. If the chimney is not presently capped, consideration should be given to capping all open unused flues with bluestone or similar material to exclude water and vermin. It is also desirable to ventilate unused flues by installing one or more brick vents in the south side of the chimney above the roof, and an equal number near its base.
- Roof and flashings: The Museum building was originally roofed with wood shingles; the underside of the roof shows plainly that the original decking boards were laid widely spaced to allow air to circulate around the backs of the shingles. Those gaps were later filled in when asphalt shingles were substituted for wood. The condition of a building's roof is arguably the most critical single factor contributing to its longevity and health. When a roof fails in its purpose of keeping water out of the structure, deterioration and decay rapidly set in. The Museum's roof does not appear presently to be in crisis, but several evident conditions combine with frank signs of past disasters to represent a cause for serious concern: Although less immediately critical than the chimney, the roof also present causes for serious concern. The asphalt shingle roofing appears in the main to be ten to fifteen years old, which means that it will be due for replacement within the next five to ten years. The copper valley flashing shows staining characteristic of eroding metal, suggesting that new valleys will be needed when the roof is next replaced. We recommend installing self-healing ice and water flashing* along all eaves and up all valleys as additional protection against ice dams and flashing failures when the main roofs are replaced.
The metal roofs beneath the east and west gables and over the porch and the basement entry appear to have reached the ends of their useful lives. Spotty corrosion is evident through the paint, indicating that the anti-rust coatings have failed. It is possible that these roofs are leaking now; if they are not, leaks are certainly imminent. These roofs should be replaced as soon as possible. The historically appropriate material is flat-seamed sheet metal. The existing roofing is either galvanized or tin-plated steel. So long as it was kept painted, hot-dip galvanized steel would be an acceptable material; other appropriate metals would be lead-coated copper or terne-plated steel. Metal roofing should be applied over a continuous ice and water shield membrane. Because of the high cost of metal roofs, consideration should be given to "rubber" (EPDM) roofing as a less expensive alternative. Since the roofs in question are not readily visible, the change of material should have little visible effect on the building. The aluminum flashing around the edges of the east and west roofs was just laid over the wall and roofing materials and nailed into place. It appears to rely on caulking compound for its effectiveness. Although common, this approach is unwise; when the (mostly concealed) caulking compound reaches the end of its very finite life, water will be able to penetrate the flashing along its upward-facing edge and through the nail holes and enter the building. When these roofs are replaced, the flashing should be completely replaced as well. Install the new flashing in accordance with good commercial roofing practice, worked into the walls and secured with concealed clips (no through-nailing!). The final roof-related exterior concern involves the flat area at the top of the building. Buildings of this style frequently were crowned with flat decks surrounded by balustrades, reminiscent of the so-called "widows' walks" found on late eighteenth and early nineteenth-century houses.* As was typical with these structures, access to the Museum building's deck is difficult, with the predictable result that little attention has been paid to the condition of the roofing and the access hatchway. One consequence was a major flood, the evidence of which pervades the interior second story.
This deck requires attention as soon as possible. At the minimum it requires complete reroofing* and reflashing, both around the access hatch and around its perimeter, where thickly applied roofing mastic speaks of long-standing problems. We would prefer, rather than just to reroof this area, to rebuild it somewhat, first to give it a pitch to ensure that water is shed and does not pool on the surface, and second, to provide a new, better flashed and more secure access hatchway. Because of the location of this deck, these changes should not be apparent from the ground.
- Drainage: As with all structures built before the advent of waterproofed basement walls, drainage of water from around the building is a particular concern. Fieldstone basement walls are highly permeable both to liquid water (from flooding of the ground above) and water vapor (from soil moisture), leading to high humidity in the basement and ultimately throughout the building.
That said, surface drainage appears more or less acceptable around much of the building, with grade located well below the basement window sills on the south, west, and north sides. It is higher along the east end, but still appears acceptable. The ground slopes well away from the building on the north and west sides, less so to the south, and poorly along the east. We recommend regrading, gently sloping the grade away from the building on all sides, and constructing swales to the east and south to lead water safely away from the building. At the east and west ends of the entrance pavilion, at its joint with the main block of the building, major roof valleys drop large amounts of water, resulting in significant erosion where the water lands and flows away, accompanied by soil build-up against the foundation wall. This area urgently needs to be regraded to lead the water away from the building and prevent ponding. In addition the ground surface should be hardened with brick or stone to arrest further erosion.
There is no readily-apparent evidence that the Museum building ever was equipped with gutters. To the contrary, the treatment of the roof edges implies that gutters were not a part of the original building, which means that to introduce them now will alter the building's historical appearance. In addition, the building's wide eaves overhangs present a challenge to any attempt to introduce downspouts in a visually appropriate way. There is no question, however, that providing a well-functioning system of gutters could, in conjunction with the regrading just discussed, alleviate the worst of the basement dampness. If gutters were to be added, we would recommend that they be as idiomatic to the building as possible--probably half-round metal, hung off the fascia on hangers. For the same historical-esthetic reason, we prefer (corrugated) round downspouts to rectangular. Discharge should be taken underground twelve feet or more away from the building to drywells.* Because of the large roof areas that they drain, the pavilion-main block junctions can be expected to be an ongoing problem, even with the addition of gutters, and deflectors at the bottoms of the valleys.
- Exterior walls: With the exception of a few easily-replaced cracked clapboards on the south side of the building, only one area on the building exterior gives us cause for concern, and it appears potentially serious: On the south side of the building, east of center, there is disconcerting evidence of gross movement between the wall and the eaves: The bed molding* has separated from the wall along much of its length, and the edge of the soffit lies an inch or more off the wall at its left end. The return of the fascia and the crown molding+ have moved away from the wall as well. These signs indicate that the wall has bowed outward in response to a minor structural failure. Since the existing roofing and flashing appear to be well connected to the building wall, it is highly likely that this movement occurred some time ago, and is presently stable.
At the same time, given this building's history of leaks and bare-bones maintenance, it is important to investigate the cause of this phenomenon and make necessary repairs. This process will probably require destructive investigation, which should be undertaken with the assistance of a skilled preservation carpenter. Begin with close inspection from a ladder. The most significant information is likely to be found in the presently-inaccessible space between the south wall of the second-story room and the roof. Access should be gained by cutting through the interior wall, rather than opening the roof itself. The corresponding area along the west part of the south wall also shows slight signs of movement. Here, though, the gap is nominal, the ends of the moldings are tight to the wall, and the soffit attaches tightly to the building, suggesting that this area is probably not a cause for present concern unless investigation of the east area discloses a major problem. - Site plantings: Two site-planting issues affect the Museum building. The first, and more serious, is the condition south of the structure. No more than fifteen feet beyond the building is a thicket of cat brier, maples, white pines, and other species. Several of the trees overhang and otherwise encroach upon the building. Close-in planting and buildings are always an uneasy mix at best; the vegetation tends to retard drying out after rain, provides a path to the building for vermin, and in more extreme cases than the situation at the Museum, abrades the structure and blocks access for inspection and maintenance. It is always desirable to maintain at least three feet horizontally and ten feet vertically between plants and building. Because these plants are in many cases good-sized trees located out of sight (and out of mind) behind the Museum, we recommend that the trees be trimmed back to leave at least twelve feet, horizontally and vertically, between them and the building. In addition, the shrubs and brier should be cut back as far from the building as politically feasible, and replaced with grass, if possible. The trees in the front yard are well separated from the building, and do not appear to pose any physical threat to it. Their appearance, however, is not particularly appropriate to the building, which they screen from the street. We would recommend removing all but the large weeping spruce. C. Interior concerns - Toilets: Decent staff toilet facilities are essential. The existing facilities are appalling, and need immediate replacement with a more attractive and sanitary facility. The Museum is small enough that a disabled-accessible toilet will not be required under the Americans With Disabilities Act. State access requirements should not be triggered so long as no more than fifty thousand dollars' worth of work is done on the building within any twenty-four-month period. Although it is certainly possible to locate a rebuilt facility in the basement, we recommend moving it to the first story, both for reasons of convenience and of cost. The matter of convenience should be obvious; as for costs, the easier access and reduced need for demolition should more than compensate for the longer pipe runs required in the upper location. Our first recommendation would be to consider the present passage between the east and west classrooms as a location.* If that space proves too small, the closet off the east classroom should offer sufficient space, although at the cost of relocating elsewhere the functions it presently fulfills.
- Insect infestation: We noted flight holes and piles of frass* in and around the wooden enclosure surrounding the west-facing window in the southwest corner of the basement, indicating an infestation of wood-destroying beetles. We believe that the collections assessor also found similar evidence in at least one stored object.
It is an urgent matter to determine the extent of this infestation and its activity. Because of the rich variety of species that can be involved, consultation with a pest-control firm is indicated to develop an appropriate course of action. In the meantime, we recommend photographing the area overall and in detail, and marking the flight holes that appear to be dropping frass, all to establish a baseline against which to compare change. Then cleaning the area and observe it monthly for the next twelve months. The appearance of new flight holes or substantial quantities of frass (beyond small amounts that may continue to trickle out the existing holes) can be taken as evidence of ongoing activity, and of the need for immediate further pest-control treatment. - Interior environment--basement: The environment inside the building is almost always an issue with small museums. Not only is commonly impossible to maintain stable conditions ideally favorable to collections* due to cost or the damage it would inflict on the museum's historic building, maintaining a reasonably clean and vermin-free space can also be an extreme challenge. In those regards, the Town Historical Museum is no exception. The building has no mechanical system whatever--the heating plant having been removed some years ago--and only rudimentary ventilation. Exacerbating the whole situation, the Museum's basement functions as a pump, moving moisture from the surrounding soil into the building.
Basements constructed of rubble masonry such as the Museum's are highly permeable, both to water vapor and to liquid water. The basement air tends to become humid, and this humidity then moves throughout the rest of the building, damaging both objects and the building itself. The most desirable course of action in a perfect world, of course, would be to introduce barriers to water movement and so prevent this humidity buildup from occurring. The plastic sheeting that was laid on the basement floor in 1991 represents an inexpensive and generally successful, if not very durable, step in this direction. By placing a membrane, otherwise known as a vapor retarder,* over the concrete floor slab the amount of water vapor entering the basement has been dramatically reduced. Unfortunately, significant amounts of water vapor--and occasionally liquid water--still enter through the walls, which are more difficult to treat.
The present plastic sheeting is subject to wear from being walked on and its joints are not tightly closed, but it represents probably the single most effect and inexpensive structural modification that can be made to reduce the amount of humidity entering the building.
Others have recommended that basement windows be left open to improve the flow of air through the space and help carry off water vapor before it accumulates to damaging levels. In principle this recommendation is sound, so long as the dew point* of the outside air is lower than the temperature of the air in the basement, which is normally the case except on hot, humid summer days. When the basement air temperature lies below the outdoor dew point, the effect of introducing outside air will be opposite to what it desired--moisture will be brought into the structure.+
In addition to common-sense monitoring, and closing basement windows during times of high outdoor humidity, ventilation through windows requires that steps be taken to maintain building security against unauthorized entry, and to prevent rain from entering. A basic building security system, which we understand the Museum has in operation, can deal with the first concern; the second may be dealt with by providing louvers outside all openable windows similar to those now in place over several basement windows. These measures can palliate the excessive humidity in the basement and can, in concert with other measures described further on, mitigate the effects of that humidity on the remainder of the building. It does not, however, appear feasible to modify the basement to the degree necessary to make it an appropriate place in which to store objects. To reduce the permeability of a stone-walled basement to an acceptable level for that purpose would require some or all of the following: Dampproof the basement floor, dampproof the basement walls, install a curtain drain outside the building, and provide at least minimal heat and mechanical dehumidification. As we have already noted, dampproofing the basement floor is the simplest of these actions to take, and has already been done. Effectively dampproofing the basement walls either requires A) excavating along the building exterior and installing a membrane that is able to accommodate both the irregularity of the wall and the minute differential movements that naturally occur in it, or B) installing a membrane on the interior of the wall and supporting it with a concrete face wall poured against the existing masonry. Both processes are expensive and stressful to the building; exterior dampproofing requires removing the earth that stabilizes the wall, and interior dampproofing subjects the building to a great quantity of water from the fresh concrete. In view of the quantity and quality of the space that would be realized, it is hard to justify the cost of either. A curtain drain would not alter the water permeability of the basement walls, but would reduce the amount of moisture entering through them by preventing the soil immediately around the building from becoming wet: An excavation would be made all around the building, beginning about a foot below the surface at the building walls and falling away at a slope of about one foot in three until it was as deep as the basement floor. Geotextile fabric* would be laid on the slope, leading to a drain at its bottom, completely encircling the building and running either to remote drywells, the Town storm drainage system, or an outfall.
Since installing a curtain drain does not require removing any of the soil that buttresses the basement walls, it is less stressful to the building than direct waterproofing. Since the drain, if correctly designed, will intercept and dispose of both roof runoff and subsurface water, it can greatly reduce the amount of moisture entering the basement. It is, however, at least as expensive a solution as waterproofing the walls themselves, and so does not appear feasible or justified in this situation. Reinstating at least minimal heating, preferably in conjunction with warm-weather dehumidification, would appear to offer substantial benefits during much of the year.* The mechanics of air and water vapor are such that a relatively small increase in temperature can result in a substantial decrease in relative humidity. This issue is discussed at length in Richard L. Kerschner's article, A practical approach to environmental requirements for collections in historic buildings, which appeared in Issue 31 (1992) of the Journal of the American Institute for Conservation.+ Mr. Kerschner's article takes the position that there are many steps that can be taken to improve the interior environment in historic-building museums short of full "new museum building" climate control, and recommends specific actions. We recommend it highly.
- Water-related damage: Water damage--resulting both from dramatic flooding and insidious chronic dampness--while widespread in the Museum's building, falls short of what we have observed elsewhere in similar situations. Primary areas of concern involve the roof, chimney, and window sash that we have already discussed, second-story finishes, and the basement stairs. The bases of both basement stairs are heavily stained and show extensive signs of chronic wetting. The stringers that carry the treads and risers are decaying; fruiting bodies of wood-destroying fungi ("mushrooms") are plentiful along the carriages beneath the west stair from its base four or five feet up toward the first floor. The east stair, while also deteriorating, is not as spectacularly involved. The increasing risk of structural failure raises a safety concern, and requires that at least the west stair--and preferably both stairs--be rebuilt within the next five years, maximum. Proper reconstruction will include raising the lowest wood a couple of inches above the cement floor and interposing damp-proof courses of sheet metal or slate between wood and masonry. The remainder of the water-caused damage appears primarily cosmetic in its effect, but it is widespread, involving much of the second story and part of the ceiling in the west first-story room. Its extensiveness makes repair into a major project, with attendant costs and inevitable disruption to stored collections. Although repairing this damage should be a high priority for action, only the most basic stabilization--such as removing dangerously loose plaster--should be undertaken until the Museum is well on the way to resolving the critical question of the building's role and purpose. - Access: The Museum qualifies as a place of public accommodation under the Americans With Disabilities Act, which requires that "readily feasible" steps be taken to improve access to disabled persons. A.D.A. is a civil rights law rather than a building code, which means that the definition of what constitutes readily feasible steps is left to guidelines and the results of litigation, and ultimately is decided on a case-by-case basis. That gloomy assessment aside, the Museum's best defense against running afoul of the Act's provisions is a plan for compliance, taking into account where the Museum presently is not accessible, alternative ways to bring the building into compliance, and the comparative feasibility of those alternatives, taking into account the Museum's annual visitation and financial resources. Listing in the National Register of Historic Places would make available a few specific historic-building mitigations. This is obviously a complex subject. For the purposes of this assessment, it appears that three steps would go far toward bringing the Museum into reasonable compliance: First, of course, is to determine immediately all the ways in which the building is not accessible.* Second, plan to provide ramp access to the first floor as part of the first major piece of work undertaken on the building.+ Third, using photographs, videotape, or some other approach, over time develop ways to give disabled visitors a sense of the second floor spaces and exhibits.
The existing exterior door in the south side of the building has been suggested as an obvious location for an accessible entrance. The necessary ramp would run parallel to the south wall of the building and then turn east around the end wall. This strikes us as an appropriate and common-sensical location, with a couple of cautions: First, except where it must touch the building at the door, space should be left between the ramp and the building to allow inspection and maintenance of both. Second, there should be a smooth, hard-surfaced walkway--for which may be possible to obtain a variance to permit it to be built later--between the ramp and the car parking area
Interior environment--upper stories: Environmental concerns in the upper stories are different from those in the basement. Specific sources of humidity are less of a concern here than in the basement; the need to develop an environment in which relative humidity is as stable and slow-changing as possible comes to the fore. The building is poorly ventilated; open windows and doors are the principal means of mitigating interior conditions. Unfortunately, with outside air come also dirt, insects, and water. All active openings need to be fitted with close-fitting screening against insects and other vermin, and effective weatherstripping, so that when doors and windows are closed they will effectively block drafts and water from entering. As for dust, short of a sophisticated mechanical system with filtered and conditioned central ventilation, there is not a great deal that can be done to reduce further the amount of material that enters the building. Fortunately, Town is a semi-rural area and the Museum sits well back from a side street, factors tending to reduce the amount of airborne contamination. Regular housekeeping will help; protected storage and display appear to be the most effective measures that can be taken for the foreseeable future. Sunlight entering the building damages objects, as well as contributing to wide daily temperature and relative humidity variation. The Museum presently keeps window shades drawn in the collections storage areas,. This is an excellent first step. The shades are old; replacing them with new and close-fitting units would be desirable, provided that the new shades are not made of vinyl or other material that may outgas substances potentially damaging to the collection. It is important to provide ultraviolet shielding over all windows where the shades are not kept drawn. Shielding products come in both adhesive films and in sheets, either flexible or rigid. We prefer to avoid the adhesive films, since as they age they become unsightly due to adhesive failure. Flexible sheets can be mounted and used like roller shades. With both ultra-violet shielding and light-blocking shades, better light control is achieved when the edges of the shades are contained in channel guides. Since sunlight causes damage even when ultraviolet shading is used,* we would like to see windows blocked with non-outgassing board to block both light and drafts. This is effectively what the plywood over the outsides of the south windows accomplishes, although it is so visually offensive that it would be unacceptable on any other face of the building. Placing the light blocking on the building interior within the window openings would cause the least offensive change in the building's appearance, interior or exterior. Since the space between the window glass and the interior closure would act as a solar collector, thought would have to be given to ventilation to prevent damagingly high temperatures in that area.
A side benefit of blocking windows in the exhibition and storage areas would be to reduce the amount of heat entering and leaving the building through the windows, and a more stable interior environment. Interior environment--off-season: During the off season when the building is not used the daily fluctuations in temperature and relative humidity are likely to be even more severe than during the rest of the year. Outdoor temperature swings of twenty to thirty degrees from coldest night to warmest day are common. Interior temperatures can fluctuate even more, depending on how the sun enters the building, producing wide extremes of relative humidity, ranging up to one hundred percent at window surfaces. Further, since the building is closed, the water vapor that continues to enter through the basement tends to accumulate in the building, with the result that the relative humidity tends to rise over the winter. The most obvious effects of this phenomenon can be seen on the window sash, where water deposited on the glass by extensive condensation has soaked the horizontal elements of the sash, destroying their finish and damaging the wood. Two strategies are needed--the one to ventilate the building to carry away excess moisture, and the other to modulate the temperature to produce a more stable relative humidity. As Richard Kerschner notes in the article to which we have referred,* providing humidistat-controlled heat is an effective way to control relative humidity: Instead of switching the heat on and off to maintain a constant temperature, it is used to maintain a stable relative humidity. As the amount of water vapor in the air increases, a small increase in temperature will keep the relative humidity from rising significantly. This form of heating does not provide comfort for building users. Its sole purpose is to even out fluctuations in relative humidity.
Because there is no need to maintain temperatures in the comfort range, heating can be minimal. Temperatures in the low forties may be adequate to maintain the desired relative humidities. Because it results in a much smaller temperature difference between outdoors and indoors, this approach offers substantial savings in operating costs over "full comfort" heating. The initial costs are somewhat higher, however, since the heating system must be able to deliver heat selectively to different parts of the building. It would be highly desirable to install such a system in the Town Historical Museum, provided the funds for installation and operation could be acquired. Ventilating the building is a more immediately-accessible option. In its simplest form it involves opening windows in the basement and the upper stories, and leaving open the doors between the second-story antechamber and the spaces communicating with the attic (to take advantage of the small vent louvers in the gables). Except for the necessary protection for windows that are to be left open,* this is a no-cost option. There is no reason not to implement it immediately.
A more sophisticated system would involve humidistat-controlled exhaust fans (with heat exchangers, if the building is heated) that would respond to elevated humidity. Consultation with an engineer familiar with the environmental needs and problems of small historic-building museums is an essential step in designing a successful system.
Because it is unlikely that the Museum's financial constraints will allow implementation of the more thorough-going and expensive solutions, it is likely that the primary point of buffering against relative humidity swings will continue to be the methods and materials used to store the collection. We understand that this matter is addressed in the collections assessor's report. - Electrical system and lighting: The present building electrical system is antiquated and inadequate on virtually every count. There is an acute need for more extensive and more controllable lighting in both storage, exhibition, and circulation space, and a critical need for more convenience outlets. In view of the other needs facing the Museum, however, this appears to represent only a moderate priority. - Interior finishes: The condition of the Museum's interior finishes varies more or less in accordance with the use to which the spaces are put. Generally speaking, finishes in the first story are in better condition than those in the second, even after eliminating seriously water-damaged areas. Because the Museum's building appears to survive substantially intact from its origin as a schoolhouse, it seems appropriate to take a conservative approach to finishes, opting gently to clean and touch up rather than to undertake wholesale removal and renewal. This approach appears particularly well suited to the first story, where, for instance, to strip and refinish wooden elements would be unnecessary, and result in excessive destruction of the building's fabric. The second story as a whole is not in as good condition as the first. Scarce maintenance resources have been focused in the first story, with the result that second-story plaster surfaces are dirty and faded, wood trim needs cleaning, and floors probably are candidates for refinishing.* More seriously, there is extensive damage resulting from at least one major roof leak, resulting in loose and fallen plaster, staining, and failing paint, compounded by the very circumstantial patches that were installed when the heating system was removed.
As we have already suggested, the first step in dealing with these more serious problems is to stabilize them by removing loose plaster and other materials that threaten to fall, installing temporary barriers and surfaces as necessary. Before undertaking more permanent repairs, though, it is important to resolve questions about the role and use of the building, since it is pointless to spend scarce money, for instance, to restore a collections storage room to its historical appearance. On the other hand, it is important that the interior finishes be sound, durable, and within the Museum's ability to provide, historically and functionally appropriate. - Window sash: Window sash throughout the building appear to be structurally sound, with finishes generally fair on the exterior and poor to fair on the interior. Years of cold-weather condensation have caused significant weathering of the horizontal elements, with total loss of finish and deterioration of the wood. Appropriate treatment includes temporarily removing the sash, stripping the finish, consolidating damaged wood and replacing missing material,* followed by regular maintenance and touch-up.+ There is no need to repair all windows at once; sash conservation and repair can be a long-term ongoing program.
A concern that is secondary to the condition of the sash is the absence of storm windows. At first thought, it would appear absurd to install storm sash on an unheated building, but benefits would result that justify considering this step. The windows in the Museum building are old and relatively permeable to drafts. This uncontrollable ventilation complicates attempts to stabilize the interior environment, regardless of whether it is undertaken through the addition of heat and mechanical ventilation or simply by leaving open selected windows and doors. The addition of storm sash would significantly reduce the amount of air infiltrating through windows.
More significantly, another layer of glazing between the interior of the building and the exterior would reduce the amount of condensation that now occurs on windows, and so mitigate the conditions leading to deterioration of those elements. We recommend that the addition of storm sash be made part of any overall conservation program for the Museum building. Whether the storms be installed on the building exterior or on the inside of the primary sash is subject to discretion. Both work well. It is sometimes argued that interior storm sash offer a bit better performance than exterior because their draft barrier is established inside the sash balance pulleys and weight pockets, which often allow drafts to circumvent the barriers. This difference is not likely to be significant, suggesting that the choice can appropriately be made on other factors. Both interior and exterior storm sash are visible; both can be finished to match the color of their surroundings. On that basis, we would opt to use standard exterior triple-track storms. They are part of the common architectural vernacular (as were wooden exterior storm sash before them); people tend not to notice them; they allow easy opening for warm-weather ventilation; they are relatively inexpensive; and they are easily reversible, should that become desirable. There is no reason not to use snug-fitting removable interior storm sash, either, although we believe that visitors would be more likely to notice them than exterior sash. D. Concerns related to the proposed new Museum space at the Public Library The museum space in the proposed Library enlargement is a remarkable statement of the Town's apparent commitment to the Museum (and the Library), and is highly commendable. At the same time, it raises some issues worth considering. It is not the place of this report to take a position for or against the move, but it is appropriate to discuss briefly some considerations bearing on that relocation. - Separation: As for to the planning of the proposed space, the gallery appears well located with respect to the relocated main entrance to the expanded library building. The amount of space allocated to the Museum appears adequate, and is in fact slightly more than the area given in the Museum's list of space needs. The amount of proposed storage space immediately adjacent to the exhibit gallery appears to offer particular flexibility in how this area is used. The separation between the proposed gallery and the upper-story storage and work space clearly represents an imperfect compromise with the ideal of keeping all museum space in a single contiguous location. What appears on the plans to be a generously-sized elevator is a great mitigation; it should facilitate moving between the two areas. This separation does, however, raise a cause for concern: At present, a single person can manage the Museum, simultaneously working in the collections storage area, controlling admission, and monitoring the exhibits gallery.* The proposed space does not lend itself readily to one-person operation. For security reasons, the gallery should not be open unattended, which means that either two staff are necessary or it will not be possible to work in the main storage and work area during gallery hours. Although it would certainly be possible to locate a bell at the gallery entrance with an annunciator in the second-story space, such an approach would be at best an awkward workaround.
- Location: The new exhibit space is located partly below grade, enclosed on two sides with fieldstone basement walls. As we have discussed elsewhere in this report, fieldstone basement walls (and plain concrete floors) admit significant amounts of water, primarily as vapor, but also as liquid. The building's architect is aware of this situation; the presentation drawings which we saw carried the notation, "Waterproofing/dampproofing required in this area." The nature and location of that work will be critical for the environment within the exhibit space. To be successful, waterproofing must be applied on the outside face of the wall or floor, so that water pressure will not push it off it over time. Attempts to waterproof the exterior of the rubble wall will be costly, will risk major damage to the building, and are unlikely to succeed over time. The wall is not monolithic; slight movements are all that will be required to compromise the barrier's effectiveness. This fact leads us to recommend to some form of a "room within a room," with waterproofing on the outside of an interior enclosure.
As both this report and the collections assessor's report have discussed, a stable environment is essential for the long-term preservation of objects. Relative humidity is particularly critical; the less it fluctuates hour-to-hour and day-to-day, the less the collections will be stressed. It would be ideal for the exhibition area and the upstairs storage area each to be separate, separately-controlled climatic zones. Assuming that operating funds were available, this approach would allow creating relatively stable environmental conditions within the museum space, regardless of conditions in the rest of the building. In any event, emphasis should be placed on maintaining a relatively constant relative humidity over a range of temperatures. Thought should also be given to the feasibility of modifying the construction in ways that will tend to uncouple the museum spaces from the rest of the building, such as insulation and vapor barriers between Museum and other space. - Autonomy: Finally, the Museum will give up its independent presence in the community in favor of a building which is clearly identified as the Library. Occupying one's own building is not, as the Museum's operators know and this report has doubtless confirmed, an easy affair. At the same time, for better or worse, much can be said in favor of having one's exclusive place, particularly when it is as characterful and as much a part of the community's history as the present structure. Moving to new space will not resolve all the problems the Museum is experiencing in its current location. Relocating will of course eliminate much of the stress of occupying an unheated and undermaintained building, to be sure, but it will also bring new challenges. At the Library, for instance, the Museum will no longer be constrained only by its own resources; it will also be affected by the Library's actions and policies, which may not always be in the Museum's best interest. A copy of our field notes, lightly edited for grammar and consistency, is an important part of all our conservation assessment reports. It allows including material that is not feasible to incorporate into the narrative report, and provides a record of conditions as we found them: ...The plaster ceiling has been replaced or overlaid with what appears to be plywood, three panels east to west and seven panels north to south. Water damage is apparent, extensively in the second panel from the north in the central range, and secondarily in the first and third panels. Minor cracking is apparent in the plaster walls. Otherwise this room appears relatively unremarkable. The ceiling water damage appears to lie directly below the area of ruined plaster and other damage in the main second-story room. Dehumidifiers are in use throughout the building, including in this space, where the machine drains via a hose through a heat register to a basement lavatory. It is questionable whether there are enough units operating (and whether the Museum could afford to operate them on its limited budget), but their existence indicates awareness of the issue and is a definite step in the right direction. Windows appear typical, in good-to-fair condition, with finishes in fair-to-poor shape. The floor is stained, and the finish needs renewal, but the floor itself appears worn but otherwise unremarkable. The other woodwork appears unremarkable, in generally good condition, with good to fair finish. The south-wall windows appear to retain their sash, but have been covered on the exterior with plywood to protect the stage curtain that is hung in front of them. The west closet appears originally to have been a supply closet. It has recently been treated very circumstantially. Original flooring and plaster wall finishes remain in part, as does what appear to be elements of the original shelving. The plaster walls show some cracking, which does not appear to represent a cause for concern. Wall paint appears to be a single coat brushed over the previous finish at an excessively thin coverage, yielding a streaky appearance. The ceiling and half the north wall are gypsum wallboard, nailed in place but not finished. The original matched-board wainscot has been replaced with unpainted plywood in this area. An adjacent plywood patch in the floor suggests that there may have been a heat or ventilation riser in the northwest corner of this space. Passage: Wall plaster shows minor cracking, but appears otherwise unremarkable. Paint has not been tended as recently as in some of the major spaces, but also appears unremarkable. There does not seem to be any immediate cause for concern here. The condition of the window and sash, woodwork, and finishes appears typical. The east classroom serves as collection storage and a curatorial work area. Its finishes and their condition appear similar to those in the west room, without the water damage noted in that ceiling. Blinds were drawn in this space, however, and lighting was generally inadequate. These conditions, coupled with the large volume of storage racks and stored objects occluding much of the wall and floor area, hampered a thorough review of the room. The door in the south wall leading to the fire escape replaces a window that formerly stood about a foot east of the present opening. The exterior door appears to be in fair to good condition; the inner door is screened, of recent vintage, and apparently unremarkable. I noted no indication that this door is causing decay or other problems in the structure below, which is encouraging (The collections assessor points out, however, that few if any of the exterior doors fit tightly in their frames, allowing drafts, precipitation, and vermin to enter. These conditions should be addressed by adjusting and weatherstripping doors and doorways wherever possible). The east closet appears more intact the one off the west room. The floor finish has worn away and needs renewal; wall and ceiling finish shows alligator-esque* cracking, indicating failure and the need to remove the existing paint before repainting. Otherwise, the room appears unremarkable.
Second story Anteroom and flanking storage spaces: Finishes here are generally unremarkable except for an extensive area of severe water damage in the ceiling. The ceiling has been resecured around the chimney with nails and plaster washers. Water damage is evident on all sides of the chimney, extending well to the east and west; the chimney itself shows water-damaged and peeling paint on its east and west faces. This damage apparently relates to a chimney leak, which has apparently been dealt with successfully for the short term by wrapping the stack in a blue polytarp above the roof. In the long term, this wrapper will accelerate the deterioration of the chimney by retarding the evaporation of moisture from the brick. The east storage space is unfinished, and has a floor of fiberboard or particleboard of comparatively recent origin. Since the space under the main-block eaves is board-floored, this work appears to replace earlier flooring. The roof structure visible in this space and between the walls and eaves of the principal room appears unremarkable, with no readily apparent signs of water staining, decay, or structural distress. The eaves appear to be tight; no daylight was visible in that area after the light was extinguished. The rear of the plaster walls appears similarly unremarkable, although in some areas the plaster keying appears minimal. This condition appears as much related to close lath spacing as anything, and therefore appears to be of long standing, and not a cause for concern. Apparently this building was originally wood-shingled. The early roof boards were laid throughout with wide spaces between adjacent members to provide ventilation for the backs of the shingles. These spaces were later filled in with narrow strips, presumably when the roof was converted from wood shingles to asphalt, which requires a continuous deck. The roof decking appears otherwise unremarkable. We did not enter the attic over the second story, due to difficult access. Looking from the top of a stepladder in the east space, it was possible to see much of the upper roof and gain a sense of its condition. As we expected, the central part of the roof is flat. A ladder leads... Copyright 1997-2008 Allen C. Hill |
