Mason - just caught your blog. What a great idea. This question may or may not rank on your list.

Many older (pre-WWII) homes in the Fan and West End areas of Richmond were constructed and finished with high-quality materials of the time, such as millwork made from old-growth hardwoods. Obviously, not all of our homes are on the historic landmarks registry, but these homes have a certain charm and scale not often found in more modern homes. In remodeling or adding-on to such a home, how do you balance the need to preserve original architectural detail against contemporary economics and new technologies, such as millwork made from engineered materials?

Jim

Jim,

That is a great question! It is an issue that we deal with regularly. There is no “right” or “wrong” answer, in my opinion; it depends on what the homeowner is attempting to accomplish with their improvements.

There are indeed many wonderful new materials and technologies available for our home improvement use these days. Considering how awful the regularly-available stock of some “old technology” materials (such as wood) is these days, such as wood products no longer commonly (or economically) available from stable, old-growth timbers, contemporary substitutes may be preferable for better performance, longevity, and economy.

An excellent example is the old style of T&G wood porch materials. If Grandma's porch floor held up well for many decades, it was likely due to the fact that it was milled from vertical grain fir or redwood. This material was likely taken from the heart of a centuries-old tree - very dense and full of naturally-protective resins. Such material is still available, but very rare and therefore extremely costly. Likewise, the earlier protective coatings were likely lead-based paint - great stuff for its intended purpose, but environmentally unsound and otherwise dangerous; therefore, no longer legal or available.

An alternative might be composite decking of some sort. There is a very nice material, Tendura (www.tendura.com) that wonderfully emulates the look and feel of the old-time porch decking, without the rot and decay problems inherent in using commonly-available wood. Love it.

We also use a great deal of PVC and composites for exterior trim - completely decay-resistant, and similar in appearance once painted. MDF is one material of choice for interior panels and moldings. Each of these exhibit particular advantages, as well as things you have to be mindful and careful of - PVC has a high coefficient of expansion and contraction due to temperature. MDF is quite moisture sensitive. One must apply this new-materials knowledge in properly detailing and installation of these materials for a successful result.

On the flip side, as you have referred-to, these materials might not be “proper” for consideration in certain aspects of a strict preservation or conservation project. I think it is the property owner's place to decide how faithful one wants to be to the original construction when making repairs or performing a replacement. Sort-of like deciding whether one wants to go OEM when restoring an old car. What is “best”? Your call.

The primary source for historic preservation guidelines in the United States is derived from the Department of the Interior, National Center for Preservation Technology and Training. http://www.ncptt.nps.gov/ A cornerstone preservation ethic, broadly stated, tells us that new work should be distinguishable from the original fabric of a structure. Therefore, one might interpret that the use of new materials in the manner that they are visibly different from the old, is actually more appropriate than an indistinguishable match. There are many dicey details that only a well-trained preservation expert (which I do not purport to be) could assist one so inclined to understand.

Here is a good example, from the NPS Preservation Brief #16 (The Use of Substitute Materials for Historic Exteriors):

http://www.nps.gov/history/hps/tps/briefs/brief16.htm#When%20to%20Consider%20Using%20Substitute%20Materials

So, if you're interested in a strict and proper conservation / preservation effort, the decisions are guided accordingly, by good expert assistance. Otherwise, there are many issues of cost, appearance, performance, and other appropriateness that you might consider.

A long-winded way to tell you that in most cases, there is no “right” or “wrong”answer.

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