Greening Historic Homes

America is a relatively young nation with a relatively young housing stock. Still, over 20 million houses in use today were built before the 1940’s. Because of their advanced age, many of these abodes present a host of problems for existing homeowners and prospective homebuyers. But they also present unique sustainable retrofitting opportunities that could help make these older homes more energy-efficient and livable, while preserving America’s cultural history.

Historical Sustainability: Greening Historic Homes

When it comes to sustainability, history can be the best teacher. After all, prior to the widespread use of modern air conditioning and lifestyles predicated on fossil fuels, people had to learn to build with nature, not against it. In order to create truly livable spaces, great care and attention was placed on crafting architectural pieces that fit regional climate characteristics. For example, homes in the arid southwest were typically build with adobe, not for the materials inherent aesthetic value (it’s simply dried mud after all), but because adobe provided effective thermal regulation in a region where night and day temperatures could vary wildly. In the same vein, old New England homes were built with steeply-pitched gabled roofs for the very practical purpose of preventing snow drifts from piling on the roof. In the south, elegant antebellum mansions, and the Victorian homes that followed, were characterized by deep, wrap-around porches, in order to protect inhabitants from the scorching southern sun and to help catch prevailing breezes.

In many ways, historical homes are inherently sustainable by design, and by necessity. Most were built from local and recycled materials. Most were designed with solar orientation and natural lighting in mind. Most took special care to promote cross ventilation and catch prevailing breezes. Most of all, well-built historical homes eliminated the significant environmental impact of building a new house from scratch. Today we are relearning many of these old lessons in order to improve the new homes we do build. Likewise, many significant improvements in home-building and sustainable technologies in the past several decades could be, and should be, applied retrospectively to historical homes in order to preserve them and bring our architectural vernaculars into the 21st century.

Remaking History In Order To Save It

As wonderful as historical homes are, functionally nearly all must be retrofitted to 21st century standards of comfort, energy efficiency, and human health. This can be an incredibly tedious and difficult process as homeowners are effectively trying to inject a hefty dose of modernity without ruining a home’s fundamental historical character. Furthermore, historical homes often come with a whole host of other unique challenges including flaking lead-based paints, shifting foundations, asbestos, and inadequate, or even nonexistent, levels of thermal insulation.

These are all major energy efficiency and sustainability problems that cannot be solved with the simple application of a visually disruptive rooftop solar array. In general, with historic architecture subtle sustainable interventions must often be made where they cannot be seen in order to retain character, which makes weatherization and other passive improvements, rather than active technologies, a good place to start.

Weatherize Old Homes: A Must

Old homes are notorious for being drafty. In a time before air conditioning, central heating, and attendant energy costs, this would not have been a major problem. But today’s fuel-intensive lifestyles mean that a leaky home is literally hemorrhaging money and adding significantly to the planet’s carbon overload. In fact, the average unweatherized home in the US leaks so much air that it would be the equivalent of having a four foot by four foot hole in the wall. Unweatherized older and historic homes likely perform even worse.

Basic weatherization could save more than $400 dollars in the first year alone, and more over time. Owners of historic homes will find that weatherstripping, caulking, insulation, and other means of sealing up a building’s envelope, are extremely cost-effective, low impact ways to weatherize their architectural treasures.

Repair or Replace?

When considering green retrofits in a historic home, one of the first questions a homeowner must ask him or herself is what to keep, and what to throw out and get replaced. In the case of historical homes, the question will hinge heavily on whether proposed changes will affect the building’s aesthetic quality and character. However, in general, historical homes that are still standing today were likely built to last with quality materials. That means that the discerning owner will often opt to repair whenever possible.

There are, of course, several important exceptions. Homes with lead-based paints, or asbestos products, must have those paints and products carefully and professionally removed and replaced. Old brick walls, however, would be a shoo in for repair as the embodied energy of the wall would likely make wholesale replacement decidedly unsustainable.

Some decisions, however, will have to be carefully approached on a case-by-case basis. For example, the Environmental Protection Agency (EPA) suggests that windows be replaced outright with energy-efficient models. However, many older wooden window frames add aesthetic value and are made to last. When considering embodied energy, an existing frame that lasts for 50 years would best be left in place and weatherized instead, rather than employing replacement aluminum frames that must be swapped out once every decade.

Incorporating High-Tech Options

Because preservation of key features is an overriding concern when it comes to historic buildings, weatherization and the employment of “passive technologies” should always be a first step when considering sustainable retrofits. However, active technologies, such as solar, wind, and geothermal, can also be incorporated with careful design and a measured approach. Geothermal can be a particularly attractive upgrade to homeowners concerned about the potential aesthetic impact active technologies can have on the exterior since it is noninvasive and virtually undetectable from the outside. Likewise, rain catchment systems, including gutters and storage cisterns, can be done in a way that blends into the existing architecture. Those looking to install wind or solar could consider installing the necessary equipment on a separate structure altogether, such as a detached carport or perhaps a shaded walkway. Other good techniques for minimizing the visual impact of renewable systems include careful site planning and placement of uncharacteristic equipment in the rear of the building.

Historical homes can be a great joy to own. They can also be a huge hassle to bring up to date and up to code in terms of energy efficiency or sustainability. Luckily, historic houses are often built to last and built with climate in mind, making them ideal starting points for sustainable retrofits. Basic weatherization and careful attention to common problem areas in older homes, such as the roof or the windows, could dramatically cut energy costs, improve comfort, and reduce demand for new far flung, car-oriented, suburban tract-homes.

Live Well. Think Green. Build Native.