Therma-Tru Home Additions & ADU Nationwide

Therma-Tru Home Additions & ADU: The Boca Raton Owner’s Guide

We stock and install Therma-Tru entry systems, patio doors, and sidelite assemblies for home additions and ADU projects in Boca Raton, with typical installed pricing from $45,000 to $130,000 for full additions and $90,000 to $220,000 for detached ADUs. Most Therma-Tru door configurations are available with 2-4 week lead times from our verified distributor network, and we carry common fiberglass slab sizes and frame kits for same-week replacement when a unit fails during an active build. Homeowners usually discover the problem when their contractor calls out a rough-opening mismatch, a warped fiberglass skin from Boca Raton’s humidity cycles, or a sidelite seal failure that showed up on our photo documentation during pre-drywall inspection.

Call (754) 254-8065

Which Therma-Tru Models This Applies To

Therma-Tru’s entry and patio door lines break into three families that matter for additions and ADUs in Boca Raton: the Classic-Craft premium fiberglass series, the Smooth-Star paint-ready line, and the Benchmark entry-level range. Each uses a different frame depth and sill profile, which determines whether the unit will sit flush in a 2×4 or 2×6 wall assembly without build-out strips.

To identify the right part, check the hinge-side label for the 8-digit model code starting with “C” (Classic-Craft), “S” (Smooth-Star), or “B” (Benchmark). The second digit indicates the door thickness: 1-3/4 inch for residential or 2-1/4 inch for impact-rated units, which Boca Raton requires in wind-borne debris regions per the Florida Building Code 6th Edition. We source OEM frames and sills directly from Therma-Tru’s Southeast distribution center in Lakeland, though we also stock compatible knock-down frames from Endura and Plastpro when the project timeline doesn’t allow for factory lead times. The aftermarket frames meet the same DP-50 pressure rating but use a composite sill rather than Therma-Tru’s aluminum-with-composite-cap design, a difference we note on the written quote so the owner chooses with the spec in front of them.

Signs Your Therma-Tru Home Additions & ADU Is Failing

• Visible fiberglass delamination or surface cracking. The gel coat on Therma-Tru fiberglass doors degrades under UV exposure, and in Boca Raton’s high-solar environment we see surface crazing after 8-12 years on south-facing units. Once moisture breaches the skin, the polyurethane core swells and the door loses its structural integrity.
• Sidelite or transom fogging between glass panes. This indicates seal failure in the insulated glass unit, which happens faster in Florida’s humidity when the desiccant inside the spacer bar saturates. The glass unit needs replacement; resealing the perimeter does not restore the thermal break.
• Frame rot at the sill or jamb, even on fiberglass units. Therma-Tru doors have composite or aluminum sills, but the rough-opening framing around them is wood. If the flashing was omitted or the pan slopes toward the house, we find OSB swelling and sill support failure during our pre-installation photo survey.
• Door binding or latch misalignment that worsens seasonally. This usually traces to frame shift in the addition’s settling structure, but it can also mean the hinge screws have backed out of the composite jamb. The distinction matters: one needs structural correction, the other needs longer screws and a hinge shim kit.
• Air infiltration or water intrusion during driving rain. On Therma-Tru units with adjustable sills, the cap seal compresses over time. In Boca Raton’s afternoon storm pattern, we see this first as staining on the interior trim at the sill corners, before the subfloor shows damage.

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After

Replacement Cost & What’s Included

For a Therma-Tru entry system replacement within an active home addition or ADU project in Boca Raton, installed pricing typically runs $2,800-$6,500 for a single prehung unit with sidelites, and $4,200-$9,800 for a double patio door with integrated blinds. Full addition projects range $45,000-$130,000, while detached ADU construction runs $90,000-$220,000 depending on square footage, foundation type, and whether the unit needs independent utility service.

The range on door-specific work reflects three variables: whether the rough opening needs reframing, whether the unit must be impact-rated for the coastal zone, and whether the interior and exterior trim is included or handled by the finish carpenter. Our written quote breaks these out line by line. Under Clause 1 of The Haven Standard, that price is fixed once signed; no change proceeds without a signed change order, which is the discipline that has kept our projects within a few percent of the agreed cost across 4,000-plus jobs since 2007. Every Therma-Tru installation carries our 365-Day Done Right Promise and a documented photo record of the rough opening, the installed unit, and the operational test before we leave.

DIY or Call Us?

A homeowner can safely verify the model code from the hinge label and measure the rough opening width, height, and wall thickness with a tape measure and level. What goes wrong after that is usually in the details: Therma-Tru’s impact-rated units weigh 140-180 pounds for a standard 3-0 door, and the fiberglass skin chips if the slab corners contact the frame during hanging. More critically, improper shimming transfers load to the jamb instead of the framing, and in Boca Raton’s high-wind zones, a poorly installed door is the first failure point in a storm.

We don’t recommend owner installation on impact-rated or sidelite assemblies. The permit inspection requires a Miami-Dade NOA certificate match, and our crews carry the documentation on the truck. If you’re mid-project and the door has failed, call (754) 254-8065. We’ll photo-document the opening, confirm the exact Therma-Tru spec, and schedule the install around your drywall and trim timeline.

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