Summer is the season that sends most Windsor homeowners looking at their windows. Nine miles north of Santa Rosa in the Russian River valley, the town runs hot and dry from late spring through fall, and single-pane or early dual-pane windows turn that heat straight into an uncomfortable, expensive interior. Bay Area Siding Company — a Larkspur-based siding and window contractor working across Sonoma County — replaces windows with units chosen to keep that solar heat out, flashed and sealed so the openings stay dry through the wet winters.

Request an estimate or call (415) 619-5167.

Start with heat: solar gain and glazing

In an inland valley climate, the single most useful thing a replacement window does is control solar heat gain — the sun energy that pours through glass on the west- and south-facing walls all afternoon. The lever for that is the glass package:

• Low-E coatings reflect a large share of the sun's heat while letting light through, which is what makes a modern dual-pane unit feel so different from the original glass in a 1990s tract home.
• Solar Heat Gain Coefficient (SHGC) is the number that describes how much of that heat gets through. California's Title 24 energy code sets ceilings on SHGC and U-factor for replacement windows, and the exact figures depend on the climate zone and the code cycle in effect — so rather than quote numbers that shift, we confirm the current Title 24 requirements at permit time and spec glass that meets them for Windsor's zone.

For a valley home, getting the glazing right is usually a bigger comfort win than any other single choice.

Fire-zone glazing, where it applies

Windsor is a wildfire-exposed community — the 2019 Kincade Fire drove evacuation orders across much of the town — and on parcels within designated fire-hazard zones, California Building Code Chapter 7A reaches the windows, not just the walls. Where it applies, an opening that's altered to install a window generally has to use multi-pane glazing with at least one tempered pane, among other requirements. That's a parcel-and-scope question, not a town-wide rule: whether your address is designated, and whether the work counts as a repair or an alteration, determines what's required. We check that with the Town of Windsor as part of scoping so the right glass is ordered the first time.

Retrofit or new-construction install

There are two ways to put a window in, and the right one depends on the condition of the opening:

• A retrofit (insert) install sets the new unit into the existing frame. It's less invasive and a good fit where the surrounding frame and flashing are sound.
• A new-construction (full-frame) install removes the window back to the framing so the flashing and water-resistive barrier can be fully renewed. It's the right call where there's rot, water intrusion, or you're re-siding at the same time and want the flashing sequenced correctly between window and cladding.

We do both and recommend based on what the openings actually show.

Choosing a brand

We install several window lines and will match the frame material — vinyl, fiberglass, aluminum-clad wood, or aluminum — to your home, your budget, and any HOA standards in your subdivision. Compare the options:

• Anlin — California-made vinyl, built for the state's climate
• Milgard — widely specced West Coast vinyl and fiberglass
• Andersen — composite and clad-wood lines
• Marvin — clad-wood, strong for character homes
• Pella — a broad range across materials

Start at the window hub for the overview, then dig into whichever line fits.

Permits and the Town of Windsor

Window replacement in Windsor is administered by the Town of Windsor Building Division under the California Building Standards Code. Because replacing windows is treated as an alteration under the energy code, a Title 24 compliance form for the fenestration is typically part of the submittal. We handle the permitting and the energy paperwork.

When it's time to replace

A quick gut check — if two or more of these are true, replacement usually beats another repair:

• Rooms that overheat every afternoon no matter what the thermostat does
• Fogging or moisture trapped between the panes (a failed seal, not fixable)
• Sashes that stick, won't lock, or won't stay open
• Drafts you can feel with the window shut, and climbing cooling bills

What affects the cost

We don't post prices because every opening is different. The drivers are the number and size of windows, the frame material and brand, retrofit vs. new-construction, whether fire-zone tempered/multi-pane glazing is required, the condition of the framing behind the trim, and access on upper stories. A walkthrough is how we price it accurately.

FAQ

Do I need a permit to replace windows in Windsor? Yes — window replacement is administered by the Town of Windsor Building Division, and because it's an energy-code alteration, a Title 24 fenestration compliance form is generally part of the submittal. We handle it.

My home is in a fire-hazard area — do my windows have to be tempered? Possibly, if the work is an alteration and your parcel is designated. In fire-hazard zones, Chapter 7A generally requires altered openings to use multi-pane glazing with at least one tempered pane. The exact requirement turns on your parcel and scope, which we confirm before ordering.

What glass should I ask for given how hot Windsor gets? Dual-pane insulated glass with a Low-E coating and an SHGC that meets current Title 24 for the local climate zone. That combination is what cuts the afternoon solar heat gain that drives valley cooling bills.

Retrofit or new-construction — which do I need? Retrofit if the existing frame and flashing are sound; new-construction if there's rot or water damage, or you want the flashing fully renewed — often the case when windows and siding are done together.

Get your Windsor windows scheduled

We're based in Larkspur and serve Sonoma County wine country. See finished work in the project gallery and the wider wine country service area. Doing the exterior envelope at once? We also handle Windsor siding replacement and Windsor James Hardie siding. To get moving, call (415) 619-5167 or request an estimate.