Boxabl Windows & Doors Nationwide

Boxabl Windows & Doors: The Sunnyvale Owner’s Guide

Boxabl-compatible windows and doors installed in Sunnyvale typically run $450-$1,200 per opening depending on size, series, and whether the rough opening needs reframing. We stock the most common Boxabl window sash, frame, and door hardware sizes on our Sunnyvale trucks, and most replacements are completed in a single visit. Most owners discover a problem when they feel a draft around the Casablanca or Boxabl Accessory Dwelling Unit door frame, or when the horizontal slider won’t lock flush against the jamb.

Call (650) 405-3637

Which Boxabl Models This Applies To

Boxabl has shipped three primary window and door configurations across its Casablanca, Boxabl ADU, and early Accessory Dwelling Unit lines. The Casablanca uses a 36-inch by 72-inch vertical slider in the main living module and a 32-inch by 80-inch steel-faced entry door with a proprietary hinge set that differs from standard residential hardware spacing by 1/8 inch. The ADU line switched to a 48-inch by 36-inch horizontal slider for the bedroom module and a wider 36-inch by 80-inch door with a multipoint locking system.

To identify your part, check the white adhesive label in the upper right corner of the window sash or the stamped code on the door hinge barrel. The first four digits indicate the manufacturing quarter; anything before Q2-2021 used a thinner .040-inch aluminum frame extrusion that cracks at the weep holes (the small drainage slots at the sill) faster than the current .050-inch spec. We carry both OEM Boxabl gaskets and frames sourced through their parts channel, plus aftermarket equivalents from Kawneer and YKK AP that match the thermal break spec and carry the same AAMA/WDMA rating. For doors, we stock the multipoint lock body and keep the older single-point hinge sets for pre-2021 units. The aftermarket route saves roughly 15-20 percent on parts and cuts lead time from three weeks to three days, which matters when you’re chasing a building inspection closeout in Sunnyvale.

Signs Your Boxabl Windows & Doors Is Failing

• Draft around the frame even when closed and locked. The compression seal, a bulb-style gasket that sits in a kerf slot (a thin groove cut into the frame), hardens in Sunnyvale’s dry summer heat and loses its memory. Once the bulb flattens, outside air channels through the meeting rail or jamb gap.
• Condensation between the glass panes. The insulated glass unit (IGU) seal has failed, allowing moist air into the spacer bar cavity. In Sunnyvale’s winter temperature swings, this accelerates; the desiccant inside the spacer saturates and the fog becomes permanent.
• Slider binds or requires shoulder pressure to move. The nylon roller trucks beneath the sash collect drywall dust and grit during Boxabl’s factory finishing process, then flat-spot against the aluminum track. The track itself can also dent if the module was craned in with the sash open.
• Door latch misses the strike plate or needs lift to engage. The steel frame modules settle slightly during the first two heating seasons, dropping the door 1/16 to 1/8 inch. The multipoint lock rods then misalign with their keepers, and forcing them stresses the gear mechanism.
• Visible daylight through the sill weep holes from inside. The sill dam (a small internal baffle that blocks wind while letting water drain) has broken or blown out. This is common in units facing the Santa Clara Valley’s afternoon wind patterns.

Before

After

Replacement Cost & What’s Included

For Sunnyvale Boxabl owners, window sash replacement runs $450-$780 per opening including the IGU or complete sash, new compression seals, and labor. Full frame-and-sash replacement, needed when the weep-hole cracking has compromised the sill or the rough opening is out of square, ranges $680-$1,200. Door hardware swaps (multipoint lock body, hinges, or full prehung unit) fall between $520 and $980 depending on whether we’re matching existing paint or installing a new steel slab.

What drives the range: frame condition, IGU size (larger bedroom sliders cost more than bathroom hopper windows), and whether the module’s interior finish needs touch-up after we pull the trim. Every quote is a flat written price with parts, labor, and disposal line-itemed separately. Under Clause 1 of the Haven Standard, that price is fixed; no change order, no surprise. Our 365-Day Done Right Promise covers the installation and the IGU seal; if the sash fogs or the slider binds inside a year, we make it right. You leave with a documented photo record of the before condition, the opened cavity, and the finished work.

DIY or Call Us?

There’s safe checking and there’s risky work. A homeowner can verify the label code, measure the sash opening width and height, and photograph the latch or lock mechanism for us to pre-stage parts. That’s useful, and we welcome it.

What we don’t recommend: removing a Boxabl window sash solo. These units are lightweight by design, but the sash on a 6-foot slider weighs 35-45 pounds and has no positive stop once you release the tilt latch. Drop it, and you’ve got broken glass plus a bent frame that turns a $600 repair into a $1,200 replacement. The multipoint door locks also require precise rod adjustment; set them too tight and the mechanism binds, too loose and the security bolt doesn’t fully engage. We’ve replaced three customer-attempted lock installs this year in Sunnyvale alone. If you’re unsure, call (650) 405-3637 and we’ll walk through what you’re seeing. If it needs a truck roll, we’ll schedule it and give you the written price before we start.

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