Beyond Paper: Preservation in Older Buildings

Jason Smith, Lewis University

While one of the most important parts of preservation is maintaining a consistent room temperature and relative humidity where archival holdings are stored, this is not always an easy task. Consistent temperature and relative humidity are important because objects degrade whenever they are outside of a comfortable range, and that range varies based on the object’s specific materials composition. However, all objects are vulnerable to large changes in humidity and temperature. As relative humidity drops, moisture is pulled out of items, causing cracking or tearing; as relative humidity increases, objects absorb moisture, contributing to mold growth and pest infestations. Archivists must do what they can to keep the ambient environments of their repositories from undergoing rapid changes.

But what happens when an institution’s repository is located in an older building? As buildings age, the foundation and infrastructure deteriorate which allows more moisture in and prevents temperature retention as hot or cold air is cycled through the gaps. In addition, older buildings may not be equipped with HVAC controls in individual rooms. In this case, the building may have  a single temperature control, usually set by a facilities manager or another individual. Archives rooms are then beholden to the level of successful operation and regulation that a central system can achieve. With building level HVAC controls, the temperature and humidity settings may not be what your different materials need. In addition, if you have objects made up of a variety of materials, you cannot set the environment to accommodate each of those materials. Below are some suggestions for these kinds of scenarios. Please note that this will be a general overview; every institution, every building, and every room is unique and should be assessed individually!

Continuous Monitoring

The most important thing is to develop a schedule to record the ambient environment. Ideally, this would be done daily and at a consistent time around the hottest part of the day which is typically 2-5 p.m. Daily monitoring will help identify when and where there are problems within the repository. You are mainly checking if the temperature and relative humidity is consistently out of a comfortable range for the materials stored in that room; if so, this means that your holdings are sustaining more deterioration than usual. It is also likely that the temperature and humidity is fluctuating a lot! While monitoring does not solve any problems on its own, it allows you to identify areas of focus and if actions to mitigate the environment are helping.

For institutions that are tight on budget, the thermometer does not have to be anything expensive. Any analog thermometer-hygrometer combination can work; these cost around $15 and are sufficient for daily monitoring. Institutions with a larger budget available can purchase and install digital monitoring devices; these allow remote data collection, historical trends, and built-in data analysis through Wi-Fi and Bluetooth connections. These allow for more efficient, convenient monitoring and automatic data review, but they can be more expensive, especially if you need to equip multiple rooms. Regardless of which you choose, both will allow you to identify problem areas in your repository.

Manageable Solutions

Because options for mitigating poor environmental conditions are limited in older buildings, it is important that Archivists use their available resources to protect their materials. Below is a list of practical suggestions that Archivists working at any size institution can employ.

1. Control humidity: If the rooms of your repository are consistently humid, it is definitely worth investing in dehumidifiers. These can be found at any home improvement store, supermarket, or online marketplace. Each unit is built for a specific range of room sizes, so be sure to know the size of the room where a humidifier is needed.. They are relatively low-maintenance, but be sure to empty the water container once it is full. The opposite is also true: if your rooms are too dry, invest in a humidifier. In either case, continue to monitor to ensure that you are not pushing the ambient environment too far into the opposite direction. 

2. Separate out your materials: If you have photographs and paper materials mixed into one room that is consistently out of the target range for temperature and humidity for these materials, move your materials to a more appropriate room. For example, if the room is too cold for paper, keep the photographs in that room and move the paper materials to a room that is a bit higher in temperature. This, of course, only works if you have multiple rooms in which to store your materials.

3. Maintain microenvironments: Ensure that, when possible, every item is contained within an acid-free folder or other enclosure; you may not think some items such as ephemera or larger, irregular-sized object need to go into enclosures, but it would benefit you to do so. Enclosures can be custom-made out of acid-free folder stock, but this is also a significant time commitment. Regardless, attempt to place as many items as you can into enclosures followed by placing them into acid-free archival boxes to create microenvironments to minimize environmental fluctuations. Microenvironments will significantly decrease the rate of degradation of all of your materials!

4. Build relationships: Develop a relationship with your institution’s facilities department, building manager, or whatever department oversees infrastructure. A facilities manager may have some further ideas about how to seal off any problem rooms and can help identify any cracks, weaknesses, or problems in the rooms that you may not even be aware of. In addition, maintaining a relationship will ensure that you are able to addresss any concerns in a timely manner as well as ensure that your materials will be safe in the case of an emergency such as floods or fires in the rooms, mold or pest infestations, etc.). This is especially helpful if you are a solo archivist or part of a small team; having an extra person or team you can count on with their own expertise is vital!

5. Block sunlight: If applicable, install curtains, blinds, or drapes over windows and check the seals on any windows. Blocking sunlight from entering the repository will reduce the temperature significantly and help  to achieve a more comfortable range. It also prevents harmful UV radiation from the sun from entering and damaging your materials. Failing seals on windows allow more moisture to enter and reduce the ability to maintain a stable temperature. Window replacements can be expensive, so work with your facilities people to see if they are able to repair the window seals before investing in new windows.

6. Check UV lighting: Finally, check the lights throughout your repository. UV radiation is extremely damaging to all materials typically held in Archives. Invest in a UV light monitor to test the lights throughout your repository. If you have any UV lights installed, or even any incandescent lightbulbs, replace them with LED bulbs that emit low or no UV radiation. This change will also slightly lower the temperature in the rooms.

Final Thoughts

While these suggestions are meant to apply to as many institutions as possible, every situation is unique. You know your institution and your holdings better than anyone else! Take what you can from these suggestions and apply them in any manner that you can. Ultimately, if you are unable to put most (or all) of these into practice, just make sure you are at least consistently monitoring and recording the ambient environment of your repository. This will help you plan for future mitigation and allow you to understand the current state of your space.
 

View additional articles in the Beyond Paper Blog Series.