Morgantown/Hart Field figures
In an average year at Morgantown/Hart Field, NOAA counts about 236 hours with the wet-bulb temperature above 73°F and about 1,187 hours above 67°F. NOAA's engineering weather data for Morgantown/Hart Field lists a 50-year basic wind speed of 90 mph (3-second gust at 33 feet), a 100-year rainfall rate of 2.7 inches per hour and about 56 freeze-thaw cycles in an average year.
Quoted as NOAA publishes them, those figures describe the station. In general terms, each exterior material answers water, freezing and slow, humid drying in its own way, which is why preparation differs so much from one wall type to the next.
Wood clapboard and shingles
Wood is what house paint was developed for, and it shows failure most plainly when water gets behind the film. It swells and shrinks with moisture, and freeze-thaw works on any wood that stays wet. Good prep means scraping loose paint, sanding edges, priming bare wood, sealing joints that should be sealed and leaving open the lap edges that let siding drain. Cedar and redwood need a stain-blocking primer to stop tannins bleeding through.
Brick
Painting unpainted brick is a one-way decision: once coated, it generally has to stay coated, and the wrong coating can hold moisture in the masonry. If you're considering it, ask about breathable masonry coatings or mineral paints made for the purpose, and whether the mortar joints need repair first. Brick that was painted before needs loose material removed and a coating compatible with what's already there. Washing brick at high pressure can damage the face and the mortar.
Aluminum siding
Old aluminum siding often chalks heavily. It needs a thorough wash, then a primer or a paint its maker says will hold on metal. Dents stay dents; paint won't disguise them.
Vinyl siding
Vinyl can be painted, but color matters: a shade darker than the original can make the panels absorb enough heat to warp. Many paint makers offer vinyl-safe color ranges for that reason. Clean thoroughly first, since vinyl collects grime and mildew.
Fiber cement
Fiber cement usually arrives factory-primed or prefinished and takes acrylic paint well when it's clean. Caulking at butt joints and trim follows the siding maker's instructions; some systems use flashing there instead of sealant.
Stucco
Stucco's rough, absorbent face uses more paint than smooth siding, and cracks should be repaired with a patching material made for stucco before coating. Elastomeric coatings can bridge fine cracks but don't suit every wall. Our exterior painting page covers coating choices.
Drying, whatever the wall
Every material still has to let its paint dry. The wet-bulb hours above count warm, humid hours at the station; in general, those slow the drying of water-based paint and can bring surfactant streaks if dew arrives before a coat has set. Starting earlier in the day leaves more drying time before evening.
West Virginia's code on painting
West Virginia's Contractor Licensing Act says the term contractor does not include a person who performs landscaping or painting services for commercial or residential customers. That is West Virginia Code 30-42-3, as worded; this page adds nothing to it.
Questions about your walls
- What does my siding or masonry need before paint?
- Which primer and topcoat do you recommend for it, and why?
- Will washing be done by hand or by pressure, and at what pressure?
- Which colors are safe on my vinyl?
- On brick or stucco, is the coating breathable?