Elizabeth Tomlinson | 7/30/2009 11:45:44 PM
Repairing or rebuilding your home after it has been damaged by a storm is enough of a challenge. Those who have historic houses have additional challenges. If your home has an historic designation or is within an historic district, you probably already know that making any changes to your home may require approval of a regulating body first. Adherence to the historic preservation regulations of your local jurisdiction is only required if your home is officially designated as an historic structure or is considered a contributing element within an historic district. National and most local historic districts contain structures that are considered either a "contributing element" - meaning their presence contributes to that which makes a district historic - or a "non-contributing element." While the state requests that structures who are non-contributing follow the national standards, it is not required.
Adherence to national standards is required if receiving federal dollars or tax credits to restore a designated structure. In this case, both the interior and exterior of the structure must follow the standards. Local jurisdictions may only require adherence to standards applying to the exterior of the home, but it is best to check the regulations in your area.
However, if your home does not carry an historic designation, you may wish to preserve the architectural integrity of the house anyway. Your local or state historic preservation agency or various preservation nonprofits can help you with understanding the historically significant features and details that are important to preserve.
Many local jurisdictions have established a governing body to oversee the historic structures and districts within their designated areas. For instance, the Historic District Landmarks Commission is the commission that oversees the New Orleans area and enforces the ordinances that regulate the historic structures and districts in their area. The Division of Historic Preservation for the state of Louisiana through the Office of Cultural Development, Department of Culture, Recreation, and Tourism offers no state historic designation, but establishes the eligibility of a structure and conducts the process required to obtain status on the National Register.
The National Register follows the Secretary of the Interior's Standards for Rehabilitation developed by the National Park Service, but is technically non-restrictive, meaning they cannot require adherence. They can, however, decide whether or not a structure is eligible for National Register status at initial application. If changes are made to a structure that is already either individually designated or a contributing element within an historic district and these changes no longer meet the requirements set forth by the NPS, the state will inform the NPS and the structure will lose its historic designation. Requirements and regulations at the local level differ by jurisdiction and in some cases are more stringent than the national standards.
A structure can be designated “historic” if it is over 50 years old, retains most of its original architectural features and character, and carries an architectural or historical importance. Preserving an historic home is not just about aesthetics. Intact historic homes serve as an architectural and historical record that can teach us about the culture and society of the time in which the structure was built. That is why it is so important that in doing repairs or rebuilding you are careful not to “alter the appearance, proportions and details of an historic building.” (National Parks Service Brief 16.) It is also important to preserve whatever evidence exists of construction techniques originally used if possible.
So what do you do if your home has been damaged in a storm-related or other event? How do you make repairs or rebuild? While your first impulse may be to tear down damaged elements, this may cost you your historic designation and future historians will lose a piece of history that can never be replaced. The most important first step is to repair or restore all elements that you can. This may require the advice of a professional. Where you may think a feature of your home is irreparably damaged, they may see a salvageable element. Preservation is always preferred, in fact required where possible, over replacement.
Some elements or materials may be beyond repair or missing altogether. In this case, the National Parks Service (NPS) lists four main circumstances in which material substitutions can be made:
1. When historic materials are no longer available
2. When there are no craftsmen skilled in the craft required
3. When there are flaws inherent in the original material
4. When building and life safety codes require a change
If you carry an historic designation, all substitutions must first be approved by the appropriate historic preservation regulatory agency. Knowing your neighbor used a certain material in the repair of his historic home is not enough. For instance, you may know that cast aluminum, precast concrete, or fiberglass have been used in past historic preservation efforts, but you must still obtain approval for their use on your home. It is important to note that each structure is considered individually by the historic preservation agency regulating your area.
According to the NPS, certain criteria must be met in order to use a substitute material. First, the new material "must be compatible with the historic material in appearance. The physical properties of the substitute material must be similar to those of the original material or be installed in a manner that tolerates differences." Lastly, the substitute material "must meet basic performance expectations over an extended period of time."
Many things go into the consideration of selecting potential substitution materials. Some material substitutes may be chemically incompatible with the older materials in which they may be in contact. Or they may be incompatible with the attachment or anchoring devices needed. In our climate, moisture penetration is a concern. If two materials in contact with or next to each other have different expansion and contraction rates, for example, cracks could occur which could allow moisture penetration. This is just one reason why chemical and physical compatibility of materials are important to consider.
Also, when looking for a substitute material, every effort should be made to match the details and craftsmanship of the original material. Look to match the color, texture, and finish of the original as closely as possible. In addition, the surface reflectivity of the substitute material, or how it reflects light, must be determined and every effort made to duplicate that of the historic material.
As stated earlier, the most important effort you make in repairing or rebuilding your historic home is to salvage and preserve whatever you can and when in doubt, to consult an expert. For instance, most people believe that in the case of historic windows, it is better to replace them because they are considered energy inefficient. According to the Louisiana State Historic Preservation Office, this is a myth. Newer windows that are double-paned or are made with Low-E glass still allow 78% of the outside heat in – called heat gain. Heat gain is exactly what we in our climatic region would like to avoid. Most people do not realize that these “energy efficient” windows are best used in colder climates because they work best at preventing heat loss, but have limited effectiveness in preventing heat gain.
However, a newer type of Low-E glass, referred to as "southern" Low-E glass or "solar shield" Low-E glass, is becoming available. It is most effective during the summer in southern climates as it reflects much of the sun's heat away from the inside of the home. Figures on how much heat still penetrates the home are hard to come by, though the science would suggest these windows do perform better in southern homes than the traditional Low-E glass. The difficulty still remains in the expense of having these windows made to closely match your original historic ones.
Regardless, the point being made is that there are ways to achieve more energy efficiency in your original windows, thereby preserving their historic value. Energy efficiency issues with older windows in Louisiana houses usually involve air infiltration. This can also be a problem with newer windows which are not installed properly as well. The air infiltration issue can be reduced or prevented with weatherization techniques and with renewing the glazing putty on your historic windows. Any heat gain issues can be combated with solar film and interior and exterior window treatments for your historic windows at a much lower expense than newer double-paned or Low-E glass windows.
Financial assistance in repairing or rebuilding your historic home may be available to you through federal grants and tax credits. Some programs may be offered at the state level. Your community might offer special programs as well. In addition, you can help protect your restored home by purchasing flood insurance through the National Flood Insurance Program or NFIP. Historic structures can be insured by the NFIP at a subsidized rate.
The task of repairing or rebuilding your historic house may seem daunting. Your state historic preservation officers, as well as, any local preservation organizations in your community can assist you through the process by answering questions and directing you to appropriate resources. The emphasis placed on preserving and salvaging whatever you can is not only often a less expensive option, but also the most sustainable one. With the proper information and action, you can successfully restore and preserve your historic home.