Where to start?
Your roof might not seem like a logical place to begin as you think about ways to weatherize your older or historic home. However, the roof is ground zero for providing a weather-tight defense against the elements – keeping water out – and central in any strategy for weatherization and increasing energy efficiency. With an estimated 30% of heat loss occurring through walls, ceiling, and floors, it makes good sense for building owners to focus on their roof to ensure that it is doing the best possible job.
However, roofs are also one of the most important character-defining features of older and historic homes and buildings. Therefore, the way you maintain, repair, and/or replace your roof matters, from the type of roofing shingles you choose to the installation of solar panels.
Of course, your roof is only one part of the equation, though often a major source for heat loss through the attic and other locations. Diagnosing whether or not your roof is performing well – in terms of energy efficiency – can be done through a comprehensive energy audit.
The following frequently asked questions are intended to not only inform and inspire, but demonstrate ways to properly care for the roof on your older building.
Diagnosing problems with your roof and keeping a weather tight "lid" on your older or historic home is imperative.
Once roofing is let go, even for a season or two, damage and deterioration can set in. The longer it is neglected, the more expensive and difficult it will be to fix.
Roofing comes in many different forms and materials. Some are highly visible and serve as prime character-defining features of older and historic buildings. There is no one-size-fits-all solution when it comes to roofing, as it is always a case-by-case situation. However, always try to honor the character of your building by maintaining the original design and materials as closely as possible.
All roofing materials deteriorate and eventually will fail over time, depending of course on the quality of the materials, their installation, routine inspection, and ongoing maintenance. Roofs are subject to natural forces like rain, snow, sun degradation, wind, and pollutants. Roofs are also commonly damaged by falling tree limbs, small animals, foot traffic, and insect infestation. In general, when roofing has failed, replace it using in-kind materials where possible.
Original roofing materials were often selected in terms of practicality, aesthetics, durability, and availability. In many ways, that still holds true today, although there are many additional options available. Substitute synthetic materials are increasingly being developed and marketed that replicate the "look" and simulate the appearance of other older styles, such as wood shingles or slate. These may be more cost effective – short-term – than replacing with original materials, though there are a lot of factors to consider before making this decision. While installation costs are important, also think about long-term durability, sustainability, authenticity, aesthetics, and the experimental nature of some of these emerging substitute products.
Does roofing offer an opportunity to go green? Are there solar solutions for older and historic homes?
Inspecting, maintaining, and repairing your existing roof is the best way to "go green" by using what you already have.
Depending on the materials, installation, and ongoing maintenance, some roofs will last longer than others.
An area that is gaining momentum – or re-emerging – is solar-powered roof systems. New technology and approaches for tapping the power of the sun are cropping up to meet the need for lower energy costs. There are generally two types – photovoltaic and thermal. Photovoltaic, or PV systems (solar panels), generate electricity from sunlight using solar cells made up into modules and arrays where each cell produces one or two watts of electricity from sunlight. Thermal systems use the energy from the sun to produce heat, not electricity, which is then usually tied to a building's water system. The method and size of installations for both systems vary, though each needs optimal sunlight conditions/placement. A new development is building-integrated photovoltaic systems, which integrate the PV or thermal systems directly into the building's materials, such as roof shingles. If installed appropriately, these systems may minimize the visual impact of traditional solar panel applications, as they are difficult to detect from standard shingles.
Overall, older and historic buildings may present unique challenges and require creative approaches, but often can be part of an overall solar solution. Some general factors to consider are:
- Irreversibility of Installations
- Location and Public Visibility
- Installations That Do Not Harm Building Materials
- Size of Systems
- Appearance (Color, Finish, Glare, Overall Shape)