Preservation vs. Green Remodeling
Historic preservation vs. energy-saving renovations
by Tim Snyder
I’ve lived most of my life in New England, and like many Yankees, I’m proud of our historic buildings. There’s a very special feeling when you drive through the center of a town and see houses that were built two centuries ago, still standing tall and proud today. It’s good to know that we have state and local organizations devoted to the preservation of these venerable structures. This public support is backed up by local historic district regulations and a strong national organization –The National Trust for Historic Preservation.
Despite such widespread support, or perhaps because of it, many people disagree about the type and scope of work that can be done to make an historic house more livable according to present-day standards. There are some obvious “no-no’s,” of course –like covering original wood clapboards with vinyl siding or installing wall-to-wall carpet over a 200-year-old pine board floor.
But once we dispense with these blatant violations of historic character, the water gets murky. Modern plumbing and electrical wiring are essential upgrades. But careful planning and good craftsmanship are required to unobtrusively integrate these amenities into the historic fabric of an antique house. Hopefully, the same careful considerations will go into selecting the cabinetry and appliances to create a modern kitchen in space that’s two centuries old.
Insulation meets historic preservation
Of all the alterations that can and should be done to ensure the survival and preserve the character of historic buildings, energy-saving upgrades should be given a high priority. I’ve recently come across negative comments with regard to filling empty wall cavities in an historic house with injection foam insulation, and it’s this kind of criticism that prompted the blog you’re reading.
Anyone who owns an antique house will tell you it’s a labor of love. But for all the pride these folks take in their historic home, they aren’t museum curators. They don’t sleep on straw mattresses or heat their bath water on a woodstove. They shouldn’t have to shiver through the winter or pay thousands of dollars in extra heating expenses just to preserve a home’s historic integrity. Making the home more energy efficient with modern insulation materials also makes it more affordable to own. Or perhaps more accurately: Spending less on heating and cooling the structure means there’s more money for making historically appropriate repairs to masonry, siding and roofing.
If it’s important to leave finished wall surfaces intact while upgrading insulation levels, injection foam and dense-pack cellulose insulation are your best options. Both materials are injected into wall cavities through holes that are later plugged and finished. Injection foam would be my first choice in an older house because of its superior ability to flow around obstructions, fill voids and seal the huge number of air leaks typically present. Instead of trapping moisture like 2-part spray polyurethane foam would (a characteristic that can damage adjacent wood), injection foam has an open-cell structure that can absorb and release moisture, enabling the wall to “breathe” while significantly improving the home’s comfort and energy performance. It’s also important to note that injection foam doesn’t outgas harmful chemicals as it cures. You won’t see technicians wearing hazmat suits when installing this insulation.
Other modern air-sealing and insulation strategies are equally useful elsewhere in an historic house. Rigid foam won’t sustain water damage or mold growth; it’s also got high R-value and air-sealing ability. Fiberglass batt insulation certainly has a longer history, but rigid foam has some admirable characteristics for old houses, and like any insulation, it can be kept out of sight.
I’m going to let Carl Elefante do the closing for this piece. The principle architect and director of Sustainable Design at Quinn / Evans Architects, Elefante coined the phrase “The greenest house is the one that’s already built.” His essay in the summer 2007 issue of the Forum Journal of the National Trust for Historic Preservation contains the following words:
“To fully capture the value of the existing building stock requires merging two disciplines: historic preservation and green building. It requires an understanding of how to respect and renew what is already here and a vision for where and how to transform the legacy of the past into the promise of tomorrow.”