The best roof for a new solar photovoltaic system is a new roof. But if you know Praxia’s work, you know, we love old buildings. So how can we mix two of our loves: renewable energy and historic preservation?
To start, it helps to understand why new roofs are the best roofs for solar. Roofs, like any part of a building, need routine maintenance over their lifetime and a roof has about the same average lifespan as a solar system; 20-25 years. So to ensure you won’t incur added costs for the dismantle and reinstallation of a solar system for that routine roof maintenance we always recommend starting with a new roof, or planning on a little renovation as part of your installation process.
That means, often the best time for an office or home to incorporate renewable energy is during their routine renovations or modernizations. All this means, solar is an option for historic homes! But if the thought of trying to renovate or touch your historic home intimidates you, maybe the idea of adding a large renewable energy producer to your roof sounds daunting. We get it. It’s hard enough to renovate your historic home, but it shouldn’t stop you from having your clean energy! Let’s break it down together. Exactly how can we incorporate renewable energy while maintaining the architectural integrity of gorgeous historic structures?!
When renovating historic structures, or buildings in historic districts, every element of that renovation must follow the Secretary of the Interior’s Standards for Rehabilitation. But only two of those standards will come into play with our solar installation.
Standard 2: The historic character of a property shall be retained and preserved. The removal of historic materials or alteration of features and spaces that characterize a property shall be avoided.
Standard 9: new additions, exterior alterations, or related new construction shall not destroy historic materials that characterize the property. The new work shall be differentiated from the old and shall be compatible with the massing, size, scale and architectural features to protect the historic integrity of the property and it’s environment.
Put even more simply: your new solar system must be as obscured from the front of your building as possible. In general, if the solar panel system cannot be seen from the ground- it will generally meet the Secreatry of the Interior’s Standards.
There are all sorts of ways to ensure that- including setting the system back from the edge a bit on a flat roof, or using the back half of a slope (facing away from the street) on a low- sloped gabled roof, or even using the cross slopes on a cross gabled roof. So just like you would find professionals knowledgeable in historic rehabilitation to put in that new kitchen, simply finding the right professionals for your solar installation is the easiest way to get your solar on that historic roof.
Maybe your house was built before electricity was invented, but that doesn’t mean you can’t join the 21st century of renewable energy production! Keep the beauty of your historic exterior, and fuel the interior with modern renewable energy. It’s the best of both worlds!
Want more information? Check out these great resources for further reading:
- Design guidelines for solar installations National Trust for Historic Preservation – National Trust for Historic Preservation
- Sample Guidelines for Solar Systems in Historic Districts National Alliance of Preservation Commissions
- Implementing Solar Panels on Historic Bildings and in Historic Districts- National Renewable Energy Laboratory (NREL)
- Illustrated Guidelines on Sustainability for Rehabilitating Historic Homes- the U.S. Department of the Interior