Moisture is the paint's real opponent
Most paint failures on a house trace back to water: water in the air slowing a fresh coat, water running down a wall from an overflowing gutter, water working into a joint and freezing. Sun and age do their share, but a repaint that doesn't deal with moisture usually starts peeling in the same places as the last one. For Winchester, NOAA's figures come from the Martinsburg, WV station, and they cover all three kinds of water.
The station figures
In an average year at Martinsburg, about 17 miles from Winchester, NOAA counts about 394 hours with the wet-bulb temperature above 73°F and about 1,460 hours above 67°F.
NOAA's engineering weather data for Martinsburg also lists a 50-year basic wind speed of 90 mph (3-second gust at 33 feet), a 100-year rainfall rate of 2.8 inches per hour and about 69 freeze-thaw cycles in an average year.
Humid hours and drying
The wet-bulb temperature combines heat and humidity. When it is high, water leaves a fresh coat of latex paint slowly. In practice that can mean:
- longer recoat times than the can suggests for ideal conditions;
- surfactant leaching, the tan or glossy streaks that appear when moisture draws soap-like ingredients to the surface of a coat that hasn't cured;
- dew on fresh paint in the evening, if the crew paints too late in the day;
- mildew on surfaces that stay damp, especially shaded walls.
A careful painter checks the label's humidity and dew-point guidance, starts after the morning dew has burned off, and finishes each side early enough for the coat to firm up before evening.
Mildew comes off before paint goes on
Paint applied over mildew doesn't kill it; the growth comes back through the new film. On a proper prep job, mildewed areas are cleaned with a mildewcide wash, rinsed and allowed to dry fully before any primer goes on. Ask the painter what they'll use and how long they'll let the house dry after washing. Many exterior paints include a mildewcide, but that protects the new film; it doesn't clean what's under it.
Heavy rain and the paint on the walls
A high rainfall rate means gutters, downspouts and drip edges matter. Where water overflows a gutter or runs behind it, it soaks fascia, trim and the siding below. Paint on that wood blisters and peels from behind, no matter how good the product. Before a repaint, look for:
- peeling concentrated under gutter ends or inside corners;
- dark streaks or soft spots on fascia boards;
- trim at the bottom of walls that splash water keeps wet.
Fix the source first. Repainting over wood that keeps getting wet only buys time.
Freeze-thaw and the joints
Freeze-thaw cycles work on any gap where water can collect. Cracked caulk, open miters on window trim and checks in old wood all let water in, and each freeze pries a little more open. Replacing failed caulk and priming bare wood are the parts of an exterior bid that deal with that. Our exterior painting page covers the order of work.
How Virginia's regulations describe the trade
Virginia's Board for Contractors regulations define a Painting and Wallcovering Contracting (PTC) specialty, covering the application of materials common to the painting and decorating industry.
That definition describes the kind of work the specialty covers. When you talk to a painter, it's fair to ask how their business is set up for the size and type of job you're planning.
Building a Winchester proposal
A useful written proposal names:
- each surface to be painted and its condition;
- how mildew, peeling and failed caulk will be dealt with;
- the primer and topcoat, by product and sheen;
- the drying and recoat times they'll allow between coats;
- what weather would make them stop for the day.
Our pricing guide explains how those items move the price, and paint sheens and finishes can help you choose between flat, satin and gloss for each surface.