Replacing windows in Fresno
Fresno's climate puts heat first. National Weather Service records for the city show 69 days at or above 100°F in 2021, the most on record; even the year with the fewest, 1956, still logged 15. In a city with that much heat, the windows facing the afternoon sun shape how comfortable a house feels for months each year.
Keeping the sun's heat out
The solar heat gain coefficient (SHGC) on a window's label measures how much of the sun's heat comes through. Lower numbers let in less. On west- and south-facing windows in Fresno, a lower SHGC can help keep rooms cooler. Many low-E coatings are designed for hot climates. Ask the contractor which coating they'd use on each side of the house, and compare SHGC across proposals.
Mild winters
NOAA's engineering weather data for Fresno records an average of only about 10 freeze-thaw cycles a year, far fewer than Reno, Boise or Spokane. That doesn't make U-factor irrelevant, because heat moves both ways and summer heat comes in through the glass and frame too. But in Fresno, SHGC usually matters more than in colder cities.
Shading still matters
Glass is only part of keeping heat out. Exterior shading, such as awnings, shade screens, trees and overhangs, stops the sun before it reaches the glass. When planning new windows, consider whether shading can do part of the work, especially on west walls.
Dust and sealing
Fresno County is part of the San Joaquin Valley area the EPA has designated nonattainment for federal fine-particle (PM2.5) standards. Windows that seal tightly and installation that air-seals the gap around each window help keep dust outside. Ask how the contractor will insulate and seal around the frames, and check the weatherstripping on sliding windows.
Aluminum frames and stucco
If your home has stucco walls and older aluminum windows without a thermal break, those frames get hot in the sun and conduct heat inside. Replacement windows for stucco homes are often designed to install over the old frame with a flange that covers the gap, avoiding stucco removal, or the contractor may cut back and patch stucco for a full-frame installation. Ask which method they propose and why.
Installing in the heat
Sealants and foams have temperature limits, and vinyl frames expand in the heat. On a summer installation day, ask the crew to follow the manufacturer's installation clearances and the sealant maker's temperature limits, and to start early.
Dark frames in extreme heat
Dark vinyl frames absorb more heat. Ask what the manufacturer says about dark colors in direct sun here.
Older homes
In houses built before 1978, lead-safe work practices apply to window replacement. Ask how the contractor will handle it.
Checking a contractor in California
California's Contractors State License Board lets you look up a contractor's license number, classification and status for free before you sign.