The Building Doctor is a program of the Ohio Historical Society’s Ohio Historic Preservation Office, helping owners, trustees, tenants and friends of older buildings throughout Ohio make informed decisions about repairs and improvements.
Water—whether it’s liquid, vapor or ice—is your old building’s worst enemy.
From the roof peak to the foundation footer, water has the power to destroy a building, given enough access and time. Keeping a building dry is probably the most beneficial endeavor for a building owner. Among the areas that require attention are basements, crawl spaces and site features.
Inspect Your Building Regularly
Inspect your building at least twice a year to look for signs of problems and to make sure that rain and snow are being carried away from your building quickly and thoroughly by sound gutters and downspouts. To eliminate the possibility that plumbing leaks are causing water-related damage, check pipes and fixtures regularly. Make sure that your dryer vent is free of clogs and ends outside.
If you have ground water infiltrating the basement floor or walls, make sure that your sump pump and floor drains are working properly. Check to see that crawl spaces are properly ventilated and that basement windows are operable. For damp basement spaces that cannot be adequately ventilated through doors or windows, use a dehumidifier that runs automatically and empties into a floor drain.
Ensure That Ground Slopes Away From Foundation
and That Downspouts Work
Outside, ensure that the ground is sloped away from the foundation and that downspouts are working properly, carrying precipitation into buried pipes or onto the ground, downhill from the foundation. If drain lines that end at the curb are not emptying any water or less than expected when it’s raining or when tested by pouring water down the originating downspout, you will probably need to hire a plumber or other professional who can check the integrity of the pipes and repair them if necessary. Metal, cement, and plastic splash blocks help direct downspouts that end on the ground away from the building.
If you have a sump pump or another pump that carries water out of your basement or other part of the building, make sure that the outfall pipe empties downhill from your building, preferably into a body of water or a swale or ditch.
For site-drainage problems that cannot be solved more simply, consider an exterior perimeter drain. A wet basement that has not responded to other solutions may benefit from interior perimeter drains. For the most intractable cases, you may decide to excavate and apply a waterproof coating to the exterior of your foundation walls.
Keep Trees Trimmed and Plantings Away From Foundation
Trees should be trimmed, so that branches do not hang over roofs. Foundation plantings should be kept at least two feet from the building and low enough to allow air and sunlight to reach the building and the ground around it. The goal is to encourage water to evaporate before it reaches your building.
Measures you take to eliminate or reduce wet conditions in your building’s basement, site and crawl space will help protect the building overall, keeping it dry and content for years to come.
For more information, read FastFacts About Wet Basements from the Ohio Historic Preservation Office and Preservation Brief 39, Holding the Line: Unwanted Moisture in Historic Buildings, from the National Park Service.
Visit the Ohio Historic Preservation Office website to learn more about preservation in Ohio and find resources for preserving the historic places in your community.
See! Save! Celebrate!
May is National Preservation Month. This year’s theme is See! Save! Celebrate! Click here to learn more about Preservation Month and find materials that you can download and use to celebrate it in your community.