Siding in Twin Falls
Twin Falls exists because of water that was moved on purpose. The Idaho State Historical Society records that Milner Dam, completed on November 15, 1904, raised the Snake River 38 feet to feed the canals that opened the Twin Falls tract, and calls it Idaho's primary Carey Act diversion structure. The project was planned by I. B. Perrine under Senator Joseph M. Carey's reclamation law of 1894, and the towns of the region, Twin Falls among them, grew up to serve the farmland the dam and its canals made possible.
A century later, water is still the thing to watch on a siding job here. Not mainly rain, but the water people put on their yards, and whatever gets behind the panels and can't get out.
About the weather figures
Other pages on this site quote NOAA engineering weather data for their towns. NOAA's engineering weather set has no station near Twin Falls; the closest, Mountain Home, is about 75 miles away, too far to stand in for local conditions. So this page gives no design temperatures, freeze-thaw counts or snow loads. Ask each bidder what winter and summer conditions they plan the installation around, and which product instructions they follow for cold-weather installs.
Sprinklers and the bottom courses
The City of Twin Falls says its drinking water is groundwater from the Snake River Plain aquifer, drawn from the Blue Lakes Well Field and the South and Southeast well and reservoir systems. Much of that water goes onto lawns and gardens, and a sprinkler head that hits the house every morning keeps the lowest courses of siding wet for much of the season.
- Walk the yard while the sprinklers run and see which walls get sprayed.
- Turn or replace heads that throw water at the siding, windows or foundation.
- Ask the contractor how much clearance they'll leave between the bottom course and the soil, mulch, patio or driveway.
- Ask what starter strip and flashing they use at the base of the wall so water that does get behind the siding drains out.
Choosing a material
Vinyl, fiber cement, engineered wood and real wood all go on houses in southern Idaho, and each has its own weak spots:
- Vinyl moves a lot as the temperature changes, so it must be hung loosely enough to slide on its nails. Ask how the installer leaves room for that movement at corners and trim.
- Fiber cement is heavy and stable, but cut ends need to be sealed and painted, and the boards need the gaps the maker specifies.
- Engineered wood needs sealed cut ends and good clearance at the bottom of the wall, where splash and snow sit.
- Real wood looks right on many older houses but needs regular paint or stain.
Ask each bidder which product they recommend for your walls, why, and for the manufacturer's installation instructions they'll follow.
Behind the panels
Most siding failures start behind the siding. A bid should say how the contractor will handle:
- the water-resistive barrier (housewrap or another product) and how its seams are lapped;
- flashing over every window and door, and kick-out flashing where a roof edge meets a wall;
- the joints around hose bibs, dryer vents, meters and light fixtures;
- damaged sheathing or framing found once the old siding is off, and how that repair is priced.
Idaho's registration law
Idaho's Contractor Registration Act has made it unlawful since January 1, 2006 to work as a contractor in Idaho without registering as the act requires. A single casual, minor or inconsequential project whose total price for labor, materials and everything else is under $2,000 is exempt. A whole-house siding job will almost always be well past that line.
Ask the contractor for their registration number, look it up on DOPL's license search, and make sure the name on the registration matches the name on the contract.
Comparing bids
Ask every bidder to price the same scope in writing: the siding product and its grade or thickness, removal and disposal of the old siding, the weather barrier, flashing, trim, soffit and fascia, sheathing repair by the sheet, cleanup, any permit, and the product and labor warranties. When two totals are far apart, the line items usually show why. Ask how long the job will take and what happens to the schedule if bad weather sets in partway through.