• Unrestored wood siding may look to be beyond repair but is usually in better condition than it looks. The preferred approach to wood siding is as follows:
    • Retain all of the sound original wood siding.
    • Repair and retain split boards by nailing and/or gluing with waterproof glue.
    • Leave concave or convex boards as they are unless there is a problem. If necessary, repair by carefully inserting flat screws in predrilled holes and gradually tighten.
    • Putty nail holes.
    • Rotten sections should be cut out using a saw, chisel or knife. The new piece to be inserted must match the original in size, profile, and dimensions. It may be a new wood board or a salvaged board.
    • Missing boards should be replaced with new or salvaged wood boards to match the original.
    • Siding should be primed and painted after being scraped of all loose paint and washed.
  • Replacement of original siding is generally justified only by documented problems with the material’s structural condition. Aesthetic reasons generally do not justify replacement. As a rule, the following are conditions which generally do justify replacement:
    • Badly rotten wood
    • Boards with splits (especially multiple splits) which cannot reasonably be repaired
    • Burned wood
    • Missing wood


  • Avoid removing the original siding. It provides important physical evidence of a building’s history and adds immeasurably to a building’s historic character. Even if replaced with new matching wood siding, the irregularities which record the building’s evolution through time and give it its character are lost. In short, the historic significance of a building where the original siding is removed is diminished. As a rule, the following reasons generally do not justify replacement:
    • To remove paint
    • To avoid repairs
    • To hide past or planned alterations
    • To increase energy efficiency
    • To restore the "original" appearance (to look "new")
  • If it is covered with insul-brick or other material, do not assume the original siding will need total replacement. Assess the situation only after total removal of the covering material. Assessment based on partial removal may lead to the wrong conclusion.
  • If replacement of siding is justified (partial or total) avoid using any material other than real wood with dimensions, profile, size and finish to match the original. Hardboard, plywood, aluminum, vinyl or other synthetic or unnaturally composed materials do not look, feel, wear, or age like the original and therefore should be avoided.
  • It is neither necessary nor, in many cases, desirable to remove all old paint from wood. Methods to accomplish total removal of paint can be damaging to the siding and should be used only with great care. The use of high pressure water blasting (over 600 psi), sandblasting, rotary sanding or a blow torch should be avoided.

Back to Renovation Guidelines
Back to Design Standards