Siding and Trim

Preventative Care for Wood Siding

Inspect once a year—find small problems before they become LARGE

  • Look for cracks, gaps, splitting wood.
  • Pay close attention to vertical seams in siding.
    • Wood can expand and contract, cause cracking.
  • Consult a professional or conduct research to do repairs on your own.
    • Fill minor gaps and cracks with a acrylic/latex caulk.
      • Inspect caulk on a regular basis, particularly in areas of intense UV exposure.
    • Do not over-seal exterior siding. A building needs to breathe and you must allow for moisture to evaporate from behind the siding.
      • The underside of lapped siding allows for some breathability, do not caulk this opening.

To extend the life of a paint job:

  • Every 2 to 3 years, clean dirt and mildew from surface with a gently cleaner.
    • Do not power wash.
    • Better options for exterior materials:
      • Clean with diluted TSP
        • Information and precautions for cleaning with TSP, please read and use with care.

Clean with a 1:10 bleach to water solution.

If have a large mold or mildew problem it could be worth investigating the area.

  • Is there moisture coming up from the ground into the walls?
  • Is there evidence of moisture on the other side of the wall that can be seen from the inside?
  • Is the wood actually rotting?
  • Is there enough airflow behind the siding?

Inspect how water is being moved away from the building. When safe, stand outside in the rain and watch where water is traveling.

  • Water running over from a gutter? Causing damage at gutter as well as splash back on ground below?
  • Leaks in downspouts?
  • Splash back from a road or sidewalk (or gutter located above)?
  • Rising damp from poor drainage under the building?
  • How is water getting away from the building?
    • Downspouts
    • Sump pump drainage
  • All surfaces within six feet of the foundation should be sloped away from house at least a ¼” per foot.
  • Are the gutters sloped correctly?
  • Address these problems as well or you will find yourself redoing the repairs soon

Siding and Building Trim Materials

Painting Wood Siding and Trim

Preparing the surface

  • The possible presence of lead paint must be addressed. Contracted labor as well as homeowners should use proper safety precautions and appropriate removal methods for any lead-based paints.
    • Lead paint is very dangerous for small children.
  • If a large amount of paint is coming loose, the surface is uneven and in poor shape:
    • Old loose paint must be removed before a new coat of paint is applied.
      • If old peeling paint is left on and new paint is placed on top, it will only be as strong as the paint below it.
      • The new paint will expand and contract at a different rate than the old paint, causing it to fail.
    • Use a high-quality primer—not fast-drying latex primer, should use slow-drying oil primer.
    • Use high quality paint—two coats (depends on color of paint).
  • If surface was recently painted and in good condition but beginning to dull and wear thin:
    • Do not need to strip down to bare wood every time a building is painted.
    • Just clean wood and do a light sanding to prepare the surface.

Do it right the first time

  • Thorough preparation of the surfaces will result in a longer lasting paint job.
    • Completely removing old paint, sanding, and priming will extend the life of a paint job.
  • Quality paint is worth the investment.
    • But without proper surface preparation even quality paint will not last.
    • Cheap out on paint and you will find yourself painting again sooner than you should need to.
      • Virginia Paint & Decorating Centers—Helpful employees, quality products

  • A large part of the cost when painting a home is the labor, realize this going into the process.
    • Does the cheapest option have the experience, licenses, and skills you need?

Space out maintenance

  • Consider painting one façade or area (e.g., a porch) of your home each year. By doing it in phases, the cost will be spread out over time.

Proper temperature for paint application

  • Generally not lower than 55 degrees F.
    • The paint can may say otherwise, but attempt at your own risk.
    • Temp needs to stay at a good level until dry. What will the temperature be in 12 hours?
  • Be wary of painting in extreme heat.
    • Paint drying too quickly can be a problem as well.


Preservation Brief 8—Aluminum and Vinyl Siding on Historic Buildings by John H. Myers, revised by Gary L. Hume

Preservation Brief 10—Exterior Paint Problems on Historic Woodwork by Kay D. Weeks and David W. Look, AIA

Preservation Brief 16—The Use of Substitute Materials on Historic Building Exteriors by H. Ward Jandl

Preservation Brief 37 – Appropriate Methods for Reducing Lead-Paint Hazards in Historic Housing by Sharon C. Park, FAIA, and Douglas C. Hicks

Preservation Brief 47—Maintaining the Exterior of Small and Medium Size Historic Buildings by Sharon C. Park, AIA

Vinyl vs. Wood Siding your House—The Old House Guy

Benjamin Moore Paints—Historical Collection

Benjamin Moore Paints—Williamsburg Color Collection