AIC's 47th Annual Meeting

Buildings are essential in preserving collections. As the primary barrier to thermal and moisture infiltration, walls, roofs and other enclosures serve as tools for preventive conservation. Their integrity is generally assumed by occupants including those entrusted with collection care. But how do we know how well they perform? Are there signals that indicate weaknesses in building components that might affect how museums operate? When envelops fail, how do we identify the cause? Enclosure problems can affect the collection environment throughout a building: RH stability Spaces along the building perimeter experience more frequent drifts in relative humidity because of their proximity to the outdoors, the creation of microclimates is exacerbated where breaches in the envelop allow moisture to migrate between the building and the exterior. Energy Use Flaws in enclosures trigger a response from building systems, particularly in museum environments where stability is paramount. The cost of running systems more frequently than necessary diverts resources from other institutional goals. Maintenance of Active Systems Systems reliability can be compromised if fans, motors and other devices frequently cycle on and off, needlessly shortening their operational life. Deterioration of the Envelop Failures in enclosures can encourage condensation within wall cavities, further undermining their integrity and creating environments that encourage the growth of mold. This presentation pairs building enclosure forensics with systems design and analysis to study how the envelop and HVAC work in concert. We will trace a typical incidence of failure, starting with observation and field investigation and then moving to more sophisticated analytical tools such as thermal imaging, WUFI and computer modeling. Having identified failure, we will discuss the implications of repair on climate control and review how active systems then respond to achieve stable conditions. The presenters will lay out the trade-offs that museums with existing buildings face: improvements to passive systems such as the envelop offer energy savings, often at a cost, and usually with implications on space and the need for ongoing preventive maintenance. We will discuss the consideration of buffer zones, areas within buildings that are less susceptible to temperature or humidity fluctuations, as lower-cost homes for collection material. And we will identify building components, such as windows or skylights, whose performance is key in creating more manageable and stable museum environments.