A siding year on the high desert
In Bend, siding isn't fighting constant rain. It's fighting freezing nights, sunny days, dry air and snow that melts and refreezes against the walls. A walk around the house each season catches small openings before the next freeze makes them bigger. The weather figures below come from NOAA's engineering weather station at Redmond, about 15 miles north of Bend, the closest station to the city.
Winter: December to February
The Redmond station's 99% winter design temperature is 9°F, and it records about 125 freeze-thaw cycles in an average year.
- Keep snow from drifting against the walls and sitting there; shovel it back from the house.
- On sunny days, watch where snow melts off the roof and runs down a wall. Those spots freeze at night and need flashing or gutter work later.
- Check for icicles at the eaves, which can mean ice dams that push water into the top of the wall.
- Keep snow blowers, ladders and shovels from hitting vinyl, which gets brittle in the cold.
- Note what you find for spring. Caulk and paint won't cure in freezing weather.
Spring: March to May
- Walk the house and photograph each wall once the snow is gone.
- Look for cracks, split boards, panels that have slipped and joints that have opened over the winter.
- Check the bottom courses and the areas under roof edges, where meltwater and refreezing do the most damage.
- Re-caulk around windows, doors, vents and hose bibs where the caulk has cracked or pulled away.
- Make sure downspouts carry water away from the foundation.
Summer: June to August
Redmond's data gives a 1% summer design temperature of 89°F with a mean coincident wet-bulb temperature of only 60°F, no hours in an average year with the wet-bulb at 73°F or higher, and about 36 hours at 93°F or hotter. That's hot, dry air and strong sun.
- Look for fading, chalking or peeling paint on the south and west walls, which take the most sun.
- Check wood siding and trim for shrinkage cracks and gaps at the ends of boards.
- Paint or stain within the temperature range on the label, and avoid painting in direct afternoon sun on the hottest days.
- Keep sprinklers pointed away from the walls; repeated wetting is how water gets into a dry-climate wall.
- Clear dry brush, bark mulch and debris from right next to the house.
Fall: September to November
- Finish repairs, caulking and painting before nights drop below freezing.
- Seal gaps where pipes, cables and vents go through the wall.
- Clean gutters after the leaves fall.
- Move firewood stacks away from the siding for the winter.
Bigger repairs
If the spring walk-around turns up more than a few pieces, get a written bid. Oregon law requires anyone who bids on or does work as a contractor to hold a current license from the Construction Contractors Board, with a residential endorsement for work on a residential structure. Look the contractor up on the CCB license search before you sign.
Keep a record
Keep each season's photos, product names and paint colors, receipts and warranties together. Matching an older profile or color is much easier when you know exactly what's on the wall.