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Double-Hung Windows in the Bay Area
Hamilton Exteriors installs double-hung windows. We measure each opening, then install the frame, sill flashing, insulated glass, seals, trim, and two operable sashes. Serving the Bay Area and Northern California.
500+ projects
Since 2018
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A double-hung window has an operable upper sash and an operable lower sash. Opening either sash gives homeowners more control over where fresh air enters while the screen and room layout remain part of the decision.
Both sashes depend on a square frame, correctly adjusted balances, aligned meeting rails, and reliable weather seals. We measure the opening and review sill, trim, wall finish, drainage, and visible damage before ordering.
Two moving sashes expose alignment problems that a fixed window can hide. We check each balance and sash path before and after perimeter sealing. The meeting rails must line up for the lock and weather seals to engage, while the screen and sill drainage remain clear for normal use.
How We Install Double-Hung Windows
The installation keeps both sashes aligned while protecting the opening from water.
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Measure the Window Opening
We document size, depth, sill condition, wall finish, trim, access, moisture evidence, and the space needed to operate both sashes.
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Prepare and Flash the Opening
The crew removes the old unit, completes approved opening repairs, and installs compatible sill flashing and water-control details.
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Install and Test Both Sashes
We set the frame, insulate and seal the perimeter, finish trim, and check balances, sash travel, locks, screens, and drainage.
Double-Hung Window Installation Check
| Item | What We Review | Installation Effect |
|---|---|---|
| Opening | Width, height, depth, square, and level | Sets frame preparation |
| Upper sash | Travel, balance, seals, and screen contact | Sets upper operation |
| Lower sash | Travel, balance, lift, and seals | Sets lower operation |
| Meeting rails | Alignment, weather seals, and lock engagement | Connects both sashes |
| Sill and perimeter | Flashing, drainage, insulation, sealant, and trim | Completes the opening |
Use Two Sashes to Control Ventilation
The upper and lower openings can serve different room conditions. We review sill height, furniture, screen location, reach, and daily use so the selected double-hung unit fits the space.
Keep the Frame Square for Both Sash Paths
Each sash needs consistent clearance and balanced support. We prepare the opening, set the frame square, fasten it without distortion, and check travel before and after perimeter sealing.
Align Meeting Rails, Seals, and Locks Together
The sashes meet at the center of the window. Their rails, weather seals, and lock must line up at the same point. We verify that connection during final operation checks.
Double-Hung Window Financing Options
Double-hung window costs can include opening repairs, sill flashing, insulated glass, frames, balances, trim, sealing, and installation. Financing is available with approved credit for eligible window replacement projects. Small standalone window projects may not qualify. During your consultation, we explain eligible work and payment timing.
Ask whether your double-hung window project qualifies for financing.
Call Now (650) 977-3351 Double-Hung Window Reviews
Verified public reviews from homeowners who hired Hamilton Exteriors.
Robert H.
via Angi
From the very first consultation, we knew we'd made the right choice. The team was knowledgeable and genuinely listened to our concerns about energy efficiency and design. We've already noticed a drop in our energy bills.
Renee D.
via HomeAdvisor
I scheduled to have someone come give me an estimate for all new windows in our 1950s home with not so great Remodeling work by previous owners. Alex Li promptly met with us & his crew throughout the entire process. They were always on time to work, left our home clean of debris & spectacular new JeldWin windows. Helped me with getting Financing as well...Just all around a great experience & highly recommend!
Ethan W.
via HomeAdvisor
I recently hired Hamilton Exteriors to replace my siding and windows, and they did a fantastic job. Their team was punctual, polite, and paid close attention to detail. The siding looks seamless, and the new windows have made a noticeable difference in both appearance and energy efficiency. Communication was always clear, and they finished on time and within budget. I’m very happy with their work and would definitely recommend them.
H.T.
via Google
I had a great experience working with Hamilton exteriors. From start to finish, their team was professional, responsive, and detail-oriented. They made the entire process smooth and stress-free, keeping me updated every step of the way. The quality of their work really stands out. Everything was done efficiently and exceeded my expectations. If you’re looking for a reliable company that takes pride in what they do, I highly recommend them!
Frequently Asked Questions
Didn't find the answer to your question? Call Now (650) 977-3351
How does a double-hung window open?
The lower sash moves upward and the upper sash moves downward. Each sash uses balances that support movement and hold the sash at the selected position.
Why choose double-hung instead of single-hung windows?
Double-hung windows add an operable upper sash. That can provide another ventilation position and, on compatible models, improve access to exterior glass surfaces.
What makes a double-hung sash hard to move?
Debris, worn balances, frame movement, sash misalignment, damaged seals, or paint can affect travel. A new installation starts with a square opening and frame.
How do you align the lock on a double-hung window?
The frame must stay square and both sashes must meet at the correct rail position. We test lock engagement after fastening, sealing, and trim work.
Can double-hung windows include insulated glass?
Yes. Available units can use insulated glass and low-emissivity coatings. Safety, privacy, exposure, and project requirements guide the final glass package.
How is the sill protected during installation?
We complete approved repairs, install compatible sill flashing, connect perimeter water-control details, seal the frame, and preserve designed drainage openings.
Get Your Double-Hung Windows Quote
Tell us about your project. We usually call within 3–5 minutes.
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