
Bring that beauty into your home with the stunning style of Bay Windows. Bay Windows feature three window panes customized to your home's style and aesthetic.
Trusted by Thousands of Homeowners Across Northern California
A bay window is three windows set in an angled frame that projects out from your wall, giving you light from three directions and a deep sill for a seat or plants. GVD Renovations & Remodeling designs, supports and installs bay windows across Sacramento and the Bay Area, with a detailed fixed-price proposal before any work starts.
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A bay window is a three-unit assembly: a large fixed center window flanked by two narrower side windows set at an angle to the wall. The angle pushes the center unit out past the siding, which creates the interior recess that makes a bay feel like extra floor space.
Each part of the assembly has a job:
Center unit: usually a fixed picture window for the widest unbroken view.
Side units (flankers): operable casement or double-hung windows that provide the ventilation.
Head board and seat board: the finished ceiling and floor of the bay. Factory boards are typically wood veneer that can be stained or painted.
Roof: a small cap that sheds water, finished in copper, painted aluminum, or shingles tied into the eave above.
Support: a hanging system anchored to the header or rafters above, or brackets below, that carries the weight of the projection.
The two standard bay angles are 30 and 45 degrees, measured between each side unit and the wall. A 45 degree bay projects farther and gives a deeper seat. A 30 degree bay stays flatter, which suits narrower walls and spots where the bay would crowd a walkway, fence or side yard.
The geometry is simple. A side unit 24 inches wide sticks out about 12 inches at 30 degrees and about 17 inches at 45 degrees, before adding frame depth. Many manufacturers, including Andersen, also build a 90 degree "box" bay, where the sides meet the wall square, which works well for a deep display shelf over a kitchen counter.
| Bay angle | Projection | Side light | Good fit for |
|---|---|---|---|
| 30 degree | Shallow | Moderate | Narrow walls, tight side yards |
| 45 degree | Deeper | More | Window seats, living rooms |
| 90 degree box | Deepest for its width | Side units face sideways | Display shelves, kitchens |
Most bays we install use one of three layouts, and the choice comes down to how you want the room to ventilate.
Picture center with casement flankers: the cranks are easy to reach across a deep seat, and casements seal tightly when closed. See our casement windows page for how they operate.
Picture center with double-hung flankers: a traditional look that matches double hung windows elsewhere on the house. Sashes are harder to lift when you lean over a wide seat.
All fixed: the most glass and the lowest cost per unit, for a room that already ventilates through other windows.
We install factory-built bay units from Andersen, where we are a Certified Contractor, and from Anlin, where we are a Certified and Authorized Dealer. Anlin's Coronado bay pairs a picture window with double-hung or casement side units and uses plywood seat and head boards with an oak veneer interior.
Yes. A bay hangs its weight outside the wall line, so it needs a header sized for the opening and a support system that keeps the seat from sagging over time. A common factory system uses adjustable chains or cables that hang the bay from the header or rafters; brackets or knee braces underneath are the other option.
If you plan to sit on the seat rather than set plants on it, tell us at the estimate, because that changes how we specify support. We also insulate the seat and head. An uninsulated seat board is one of the most common reasons an old bay feels cold in winter and hot in a Sacramento July.
Many 1970s to 1990s homes in the region have aluminum bays with rotted seat boards or leaking roof caps. Replacing a bay with a new bay usually reuses the existing header and opening once we confirm the framing is sound. Replacing a bay with a flat window means rebuilding the wall section, which adds framing, siding or stucco, and interior drywall work.
A bay uses three units at sharp 30 or 45 degree angles, while a bow uses four to six units in a gentle curve. A bay gives a deeper, more defined seat on a medium-width wall; a bow spreads glass across a wider wall. If you are weighing both, our bow windows page covers how curved arcs are configured.
A bay catches sun from three directions, so the glass package matters more than on a flat window. On west and south walls, specify dual-pane low-E glass with a low solar heat gain coefficient (SHGC); otherwise a bay seat becomes the hottest spot in the room on a 105 degree afternoon.
Under California's Title 24 2025 code, replacement windows in Sacramento's Climate Zone 12 need a U-factor of 0.27 or lower and an SHGC of 0.23 or lower, with looser limits when you replace 75 square feet of windows or less. Our energy-efficient windows page explains frame and glass choices in more depth. Bay Area coastal homes benefit from the same glass for noise and winter heat loss rather than summer heat.
A bay costs several times what a single window does, because you are buying three units plus a seat, head, roof and support system. The biggest swing factors are frame material, overall width, angle, glass package, and whether the opening needs a new or enlarged header.
Replacing an existing bay in the same opening costs least. Converting a flat window to a bay costs most, because it adds structural work, roofing and exterior patching. Installed per-window ranges by frame material are on our replacement windows page; for a bay, we give you one fixed total after measuring, so the number you approve is the number you pay.
A new bay in a larger or new opening usually needs a building permit because it involves a header. A same-size replacement may need less review, depending on your city. Our guide on when window replacement needs a permit covers the details, and when a permit is required, we handle it.
At the free in-home estimate we measure the opening, check the header and framing, and go over angle, glass, color and seat options.
You receive a detailed fixed-price proposal with the full scope.
We file the permit if one is required and order the bay. Lead time is 8 to 10 weeks, or 10 to 12 for custom products, excluding delivery.
Our crew removes the old window, repairs or installs framing, then sets, supports, insulates and flashes the new bay and its roof.
We finish interior trim and exterior seal, clean up, and walk through the work with you.
A dedicated project manager coordinates the structural, window and finish work, and our own trained crews do the installation. We are family-owned, hold California contractor license #989637, and carry general liability and workers' compensation insurance.
We hold strong ratings across hundreds of verified reviews on Google, Yelp and other platforms, plus an A+ from the Better Business Bureau. You can see frame samples and glass options at our Rocklin showroom at 6848 Five Star Blvd #6. Combo, senior and military discounts are available, and financing through third-party lenders lets you check eligibility without affecting your credit score; approval, rates and terms depend on credit.
We install bay windows across the Sacramento region, including Roseville, Rocklin, Folsom, El Dorado Hills, Granite Bay, Lincoln, Elk Grove and Davis, plus Oakland, Berkeley, Concord, Walnut Creek, San Jose, the North Bay and Lake Tahoe/Truckee.
Book a free in-home estimate and we will check your wall, recommend an angle and configuration, and give you a firm total in writing.
Compare the window styles and brands we install across the Sacramento area.







