Evaluating the Exterior Condition of Your Historic Building | Wisconsin Historical Society

Guide or Instruction

Evaluating the Exterior Condition of Your Historic Building

Evaluating the Exterior Condition of Your Historic Building | Wisconsin Historical Society

Planning a historic house or building rehabilitation project is a complex process, so you might want to hire professionals to plan your project. But even if you intend to hire others to plan your project, you should understand the existing conditions of your house or building. The process of visually evaluating the exterior condition of your structure will help you be an informed consumer. It will also show the professionals you hire that you are knowledgeable about your own building.

Gather Your Tools and Supplies

To properly evaluate the exterior condition of your house or building, you'll need the following tools and supplies:

  1. Notebook or a small hand-held tape/digital recorder to document what you see
  2. Binoculars to see areas you cannot reach
  3. Camera with a zoom feature for close-ups
  4. Flathead screwdriver, awl or ice pick for poking into old wood and other materials
  5. Pocket knife for scraping away dirt and paint
  6. Small magnet to determine whether metals are steel, lead, copper or brass

Conduct a Visual Assessment

To conduct a complete visual assessment, you must look over the outside of your house or building from top to bottom. Take good notes and photos of every part of the exterior and its condition.

1. Get an overall view. Stand across the street from your house or building and look at how it sits on the lot. If your building appears to be leaning to one side or the other, it could be a sign of foundation settling. Look down the sides, back and front of your building to assess whether the walls seem straight or appear to be bowing in or out. Walk around the entire exterior and identify areas with peeling paint, wood rot or metal cornice deterioration. Use binoculars to look closely at the cornices, eaves and upper vertical walls.

EnlargeMasonry chimney

Dane County. The copper flashing is properly installed at this masonry chimney. Note the flashing is placed within the mortar joints and not the stone itself. This type of installation is called Step Flashing. Source: WHS - State Historic Preservation Office.

2. Inspect your masonry and mortar joints. If your house or building is constructed with masonry, look for bricks, stones and mortar joints that are missing or deteriorated. Pay special attention to cracks in the masonry. Masonry cracks usually indicate some type of structural problem. Inspect the mortar joints. If the mortar is separated in areas (not secured to the masonry above and below), it is a sign that your building may need repointing.

3. Inspect your siding. Inspect your siding and make note of any non-original exterior wall coverings. The original exterior of many historic houses have been covered with replacement siding, and the façade of many commercial building have been covered over with a slipcover. Replacement sidings and slipcovers can include aluminum, vinyl, asbestos slate, synthetic stone and even Art Deco glass elements. Most of these coverings are actually damaging to the facade and should be removed during your rehabilitation project. However, some changes may have become historically significant themselves and should not be removed.

4. Inspect wood elements. Use a screwdriver, awl or ice pick to poke around the wood elements of your house or building’s exterior, including the wood siding, windows, window trim, door and door trim. Look for peeling paint, wood splits and wood rot. Wood elements tend to rot from the top down or bottom up, so pay particular attention to window heads and sills, the bottom few boards of the siding, and the eaves and soffits.

5.  Inspect your windows. Look at the bottom of your wood or metal window frames for water staining or wood rot. The glazing compound that holds the glass in the frame should be continuous and firm but not brittle. If the glazing compound is cracked or portions are missing, you will have to replace the glazing compound. If you have a commercial storefront, look closely at the large storefront glass for cracked glass or signs of excess moisture. Insulated glass has a tendency over time, to get condensation between the panes of glass, which is a sign the window has failed.

6. Evaluate the roof drainage. Observe how water is moving away from or into your house or building. Your downspouts should be directing water away from the building, not into it. Check the ground around the building; groundwater should flow away from, not into, the foundation. Note whether your gutters are sagging or have holes in them. Both of these conditions will cause water to get into places where it could cause damage.

7. Inspect your parapets. Many historic buildings have a brick sidewall rising above the roof called a parapet. If your building has parapets, look for brick deterioration and failed flashing. Flashing stops the water on the roof from entering the areas where the roof meets the wall or where pipes penetrate the roofing material. Gaps or deterioration in these metal flashings can cause leaks. Parapet flashings and penetrations should not be tarred, because they will leak. Metal flashings on the parapet should be bent at the top and tucked into the mortar joints.

8. Evaluate the roof condition. Consult a roofing professional to check your roof for signs of deterioration. Many houses and buildings have a hatch on the roof or a fire escape that can provide roof access. Make certain the professional you hire walks the entire roof area to do the following:

  • Note any areas that feel soggy or unstable. Look for holes or cracks in the roofing material.
  • Look for areas where water isn't draining, called ponding.
  • Check the roof drains to make certain they are draining. Many low-slope roofs have roof drains in the body of the roof or drainage holes at roof level through the parapet walls.
  • Look for metal flue liners that emerge through the top of your chimney from gas appliances such as furnaces and water heaters. If the liners do not emerge from the top of your chimney, your chimney probably was not lined properly. Liners are important because the carbon monoxide in the gasses can cause brick and mortar to deteriorate.

The information presented here is not intended to provide comprehensive technical advice or instructions on solving historic preservation issues. Any information contained or referenced is meant to provide a basic understanding of historic preservation practices. Read full disclaimer.