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Rehab Do’s and Don’ts

a woman repairing a window

Tonya Taylor works on a window

Roofs:

  • Though wood shingles are the most common historic roofing material, less expensive asphalt shingles are an acceptable replacement. If you choose to invest in wood shingles, use the more historically accurate, thinner sawn shingles rather than the heavy, split shake shingles.
  • Avoid concrete or clay tile, aluminum shingles, and other metal roofing materials that are not compatible with the architectural style or age of your building.
  • Avoid adding dormer windows to the front of your house; they are much less intrusive on the rear roof slope and even on the sides.

Exterior Walls:

  • Never sandblast to clean or remove paint from brick walls; use appropriate chemical cleaners and low pressure (400 psi maximum) wash instead. Sandblasting and high-pressure washes permanently damage the protective outer layer of the brick. Always clean small test patches first in order to determine the gentlest effective method.
  • Repoint (replace) deteriorated mortar with a softer, high-lime content mortar rather than modern mortar, which is made up mostly of portland cement. Modern mortar is stronger than the old brick. With modern mortar, as as the building expands and contracts through the seasons, the brick will be the first to crack. A basic historic mortar mix contains one part lime to three parts sand. Contact our office for more details on a mortar mix appropriate for your building.
  • Avoid aluminum or vinyl siding, even on soffit and eaves. They often obscure architectural details, can trap moisture inside the wall, and are not as maintenance-free as their manufacturers would lead us to believe (dents and scratches can’t be fixed, paint colors fade over time, etc.).
  • Exterior woodwork can be protected from the elements with a good paint job. This includes proper preparation of the surface and the right kind of paint (oil-base paints hold up better than acrylic).

Windows:

  • Avoid enlarging window openings or closing them off.
  • Whenever possible, repair rather than replace historic window frames. Old frames can be made weather-tight and can often be adapted to accommodate double-pane glass. If you must replace them, select windows that match the original as closely as possible. A list of window manufacturers and contractors who repair windows is available from
    the State Historic Preservation Office.
  • Storm windows on the interior rather than the exterior are less visible and often cheaper.
  • Avoid using tinted or mirror-finish glass in windows; they are inappropriate on historic buildings.

Additions:

  • Keep new additions to the rear, where they are less visible, and make them narrower and shorter than the original building. If an addition on the side cannot be avoided, set it back as far as possible so the shape of the original house is still discernable. Try to match the original roof pitch, window shapes, eave width, etc.
  • Avoid attaching garages to historic houses whenever possible. A free-standing garage or one attached with an inconspicuous connector or breezeway is preferred.

Kitchens and Bathrooms:

  • These rooms often need to be upgraded with new fixtures, etc., but this can be done so they complement the original house rather than detract from it.

What contractors know how to do the work correctly?

The State Historic Preservation Office has a list of contractors with experience working on older buildings.