Window Replacement Across the Bay Area

A good window replacement starts with two decisions: whether to keep the existing frame or go back to the rough opening, and which frame material suits your home and climate.

Window replacement & installationRetrofit or full-frameLarkspur, Marin County(415) 619-5167

Bay Area Siding Company replaces windows on homes throughout the SF Bay Area, from foggy coastal neighborhoods to hot inland valleys. Because we work on the whole exterior wall, we treat every window as part of the wall assembly. It has to shed water into the flashing and water-resistive barrier behind it, not just fill a hole.

Not sure whether you need retrofit or full-frame? Schedule a consultation and we'll look at your openings with you.

Call (415) 619-5167

When is it time to replace your windows?

Is fog between the panes a reason to replace?

Condensation inside a dual-pane unit means the seal has failed and the insulating gas or dry air is gone. The frame may still be sound, so the choice becomes replacing the glass unit or the whole window. That depends on the age of the frame, how the sashes operate, and whether other windows are close behind.

What about soft sills, stains, or water on the interior trim?

These are the signs to take most seriously. Water showing up inside usually points to a flashing or sill problem, not just a tired window. A common finding when the trim comes off is a sill with no pan flashing, or a head that was never lapped under the building paper. That situation generally calls for full-frame replacement so the opening itself can be inspected and corrected.

My single-pane aluminum windows still work. Should I replace them?

Many 1950s–70s Bay Area homes, including Eichlers and mid-century tract homes, still have original single-pane aluminum. If they operate and don't leak, there's no emergency. Replacement mainly improves comfort, condensation control, and noise, so it's a reasonable upgrade you can plan and budget for.

Retrofit or full-frame: how do I choose?

A retrofit (insert) window fits inside the existing frame, which is left in place, so interior and exterior finishes stay largely undisturbed. A full-frame (new-construction) install removes everything down to the rough opening so the sill, flashing, and WRB integration can be rebuilt. Retrofit is a sensible choice when the existing frame is sound and dry. Full-frame is the right call when there's water damage, rot, or you're re-siding anyway.

Window frame materials compared

Frame	Genuine strengths	Honest trade-offs	Often a good fit for
Vinyl	Low maintenance, multi-chamber frames that insulate well, never needs paint, generally lower upfront cost	Frames tend to be wider than metal or fiberglass; color choices and paintability vary by line; expands and contracts more with temperature than some other materials	Budget-conscious projects where low maintenance and lower upfront cost matter
Fiberglass	Very dimensionally stable (moves at a rate close to glass), strong, allows slimmer frames, can be painted	Typically costs more than vinyl; fewer style options in some lines	Homes with big temperature swings, darker exterior colors, or a preference for narrow frames
Wood (incl. clad wood)	Traditional look and warm interior finish, detailed profiles, suited to period homes	Exposed wood needs regular paint or finish upkeep; exterior cladding reduces that but adds cost	Victorians, Craftsman homes, and remodels where historic character matters
Aluminum	Strong and slim, so sightlines are thin and large openings are practical; modern appearance	Metal conducts heat, so thermally broken frames matter for comfort and condensation	Mid-century modern and Eichler-style homes, large glass walls
Composite	Blends of materials engineered for stability and low maintenance, often with a wood-like appearance	Usually priced above vinyl; properties vary a good deal from one manufacturer's formulation to another	Homeowners wanting a wood look with less upkeep

Energy efficiency and Title 24, in plain terms

A window's energy performance comes mostly from the glass package: dual-pane units, low-emissivity (low-E) coatings, gas fills, and warm-edge spacers. The frame adds to this, particularly with metal frames, where a thermal break makes a noticeable difference. Every qualifying window carries an NFRC label listing its tested performance, so options from different brands can be compared on the same terms.

The Bay Area's climates differ a lot within a short drive. Near the coast, the marine layer keeps things cool and damp, so insulating value and resistance to interior condensation are usually the priorities. Inland, strong summer sun and heat make solar heat gain a bigger concern, and a low-E coating that limits it can make west-facing rooms much more comfortable. We choose the glass package for the exposure, not by habit.

California's energy code, Title 24, sets performance requirements for replacement windows, and those requirements are updated periodically and depend on climate zone. Rather than rely on remembered numbers, we confirm the current requirements with your local building department (the authority having jurisdiction, or AHJ) when we pull the permit. The same applies to safety glazing near doors and wet areas, bedroom emergency-escape openings, and glazing rules under Chapter 7A on parcels mapped in Cal Fire fire-hazard severity zones. Chapter 7A covers specific assemblies such as exterior glazing, not every material on the house.

What drives the cost of window replacement

Retrofit vs. full-frame: Full-frame means removing and restoring exterior and interior finishes around each opening, so it involves more labor than a retrofit insert.
Your wall finish: Full-frame work in stucco requires cutting back and patching the stucco, which differs from work in lap siding or shingles.
Frame material and product line: Vinyl, fiberglass, wood, aluminum, and composite sit at different price levels, and each brand offers several tiers.
Glass package and options: Low-E choice, tempered or laminated glass, obscure glass, grids, and specialty colors all affect cost.
Size, shape, and operation: Large units, custom shapes, and operating styles such as casements or sliders are priced differently from standard sizes.
Hidden conditions: Rot in sills or framing, missing flashing, or damaged sheathing found once an opening is exposed has to be repaired before the new window goes in.

Our installation process

Consultation and measurement. We look at each opening from inside and out, check for signs of water intrusion, explain whether retrofit or full-frame fits, and take precise measurements for ordering.
Permit and product confirmation. Where required, we pull the permit and confirm current energy, safety-glazing, egress, and any Chapter 7A requirements with the AHJ before ordering.
Careful removal. For a retrofit, we remove the old sashes and stops and leave the existing frame in place. For full-frame, we remove the unit and surrounding trim or finish back to the rough opening.
Inspect the opening. We check the sill, jambs, and surrounding sheathing for rot, and look at how the existing WRB and flashing are, or aren't, tied into the opening.
Repairs and flashing. Damaged wood is replaced, and on full-frame installs we build a sloped sill pan and lap the jamb and head flashing shingle-style with the WRB so water drains outward.
Install to manufacturer spec. The window is set, shimmed plumb, level, and square, fastened per the manufacturer's installation instructions, and insulated around the perimeter with a product that won't bow the frame.
Finish and walkthrough. We seal, restore trim and finishes, clean up, and walk each window with you to confirm it operates, locks, and seals properly.

Why homeowners choose Bay Area Siding Company

Windows fail at the joint between the unit and the wall more often than in the unit itself. We're an exterior-wall contractor, so we give that joint as much attention as the window.

Assembly-first installs

Flashing, sill pans, and WRB integration are part of the scope from the start, not an afterthought.

Honest, clear scope

We'll tell you when a retrofit is perfectly adequate and when an opening needs full-frame work, and write the estimate to match.

Marin-based, Bay Area-wide

We're based in Larkspur, serve the wider Bay Area, and you can reach us directly at (415) 619-5167.

How to vet a window contractor

Verify their license status at cslb.ca.gov before signing anything.
Ask whether the quote is retrofit or full-frame, and why that method suits each opening.
Ask how they flash the sill and head. A vague answer, or "caulk will handle it," is a warning sign.
Confirm who pulls the permit and that energy and safety-glazing requirements will be checked with the building department.
Make sure the estimate names the brand, product line, frame material, and glass package, so you can compare quotes fairly.
Ask how hidden rot or damage will be handled and priced if it's found during removal.

Other services we offer

Looking at specific window brands? We install several, and each page covers its lines and trade-offs.

Milgard windows Anlin windows Andersen windows Pella windows

Window Replacement FAQ

My house is stucco. Do I have to do full-frame?

No. Retrofit windows are common on Bay Area stucco homes because they avoid cutting and patching the stucco. If there are signs of water getting in around an opening, full-frame is worth considering so the flashing can be corrected, with a stucco patch afterward.

Do I need a permit to replace windows?

Many Bay Area jurisdictions require one, and requirements vary by city and county. We confirm with your local building department and handle the permit where one is needed.

Which frame holds up best near the coast?

Salt air and constant marine-layer moisture are hard on exposed finishes and hardware. Vinyl, fiberglass, and well-finished composite or clad frames generally handle it well. Hardware and fastener choices matter too, and we follow each manufacturer's guidance for coastal exposure.

Can I replace just a few windows now and the rest later?

Yes. Phasing is common. We'll note the product line and options used so later windows match in appearance and operation.

Will new windows help with street noise?

Dual-pane units help compared to single-pane, and laminated glass or dissimilar glass thicknesses can reduce noise further. A well-sealed installation matters as much as the glass.

Ready to talk through retrofit vs. full-frame and the right frame for your home? Request an estimate today.

Call (415) 619-5167