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Therma-Tru Door Installation: The Kendall Owner’s Guide
Therma-Tru door installation in Kendall typically runs $1,800 to $4,200 for a complete entry system, depending on whether you’re replacing a slab in an existing frame or installing a full pre-hung unit with sidelites. We stock Therma-Tru-compatible components for same-day resolution of most failure points, and we carry the full Classic-Craft, Fiber-Classic, and Smooth-Star series lines. Most Kendall homeowners discover their Therma-Tru door needs attention when the fiberglass skin starts separating at the stile, the sill pan leaks during our summer deluges, or the multipoint lockset throws out of alignment after a few seasons of humidity swelling.
Which Therma-Tru Models This Applies To
Therma-Tru organizes its entry door lines by substrate and aesthetic tier, and the installation approach differs materially between them. The Fiber-Classic series uses a wood-grain embossed fiberglass skin over a polyurethane core; Smooth-Star offers a paint-ready fiberglass surface; Classic-Craft carries the highest grain definition and heaviest edge construction. Each requires a specific jamb width, and Kendall’s post-1995 construction tends toward 4-9/16″ jambs while older Dadeland-area homes often need 6-9/16″ for thicker wall sections.
We identify the correct replacement by the spec label on the door edge, which carries the series code, size, and swing hand. The OEM-vs.-aftermarket question for Therma-Tru is straightforward: we use factory hinges, sill components, and weatherstrip because the tolerances are tight, but we source multipoint hardware from quality equivalents when the Baldwin or Hoppe OEM lead time stretches past what a compromised door can wait through. One compatibility gotcha we’ve tracked in Kendall: Classic-Craft Canvas and Mahogany collections use different edge profiles, and swapping hardware between them without a jamb reassessment will leave you with a gap or a bind.
Signs Your Therma-Tru Door Installation Is Failing

- Water staining at the sill or base of the jamb. Therma-Tru’s composite sill is durable but the end-seals and corner pads degrade faster in Kendall’s UV exposure than the manufacturer rates for northern climates. We replace the full sill pan assembly, not just the cap, because the sub-sill channel is where the rot starts.
- Multipoint lock bolts misalign with strikes. The three-point or five-point lock system depends on precise jamb plumb. South Florida’s slab settling, common in the limestone substrate around Kendall, throws the alignment. Adjusting the keeps without checking frame square wastes your time.
- Fiberglass skin delamination at the lock stile. The skin separates from the stile edge when moisture wicks through fastener holes or the lock bore. This is structural; cosmetic repair won’t hold. We see this most on west-facing entries in Kendall where afternoon sun drives thermal cycling.
- Door drags or binds seasonally. Humidity expansion of the jamb, not the door itself, is the usual cause. Therma-Tru’s fiberglass is dimensionally stable, but the frame it’s hung in is not. We check jamb fastener spacing and shim integrity before blaming the slab.
- Visible daylight around the perimeter seal. The Q-Lon or silicone bulb weatherstrip compresses permanently after five to seven years in Florida heat. OEM replacement strip restores the seal; generic substitute often lacks the correct fin profile for Therma-Tru’s kerf.
Before
AfterReplacement Cost & What’s Included
| Service | Price Range |
|---|---|
| Slab replacement in existing frame | $1,800 - $2,800 |
| Pre-hung unit, standard single door | $2,400 - $3,600 |
| Pre-hung with sidelites | $3,200 - $4,200 |
| Sill pan / threshold replacement only | $480 - $720 |
| Multipoint lockset replacement | $340 - $580 |
What drives the range: jamb condition, whether the existing frame can be preserved, and whether the opening needs reframing for plumb. Our quote includes the measured survey you keep, the written scope with line-item pricing, permits pulled and inspections passed where required by Miami-Dade code, and the documented photo record on completion. The 365-Day Done Right Promise applies to every Therma-Tru installation we perform in Kendall. We also handle PGT, CGI, and CWS door systems if your opening calls for impact-rated specifications instead.
DIY or Call Us?

There’s a clear line between what a homeowner can verify and what requires the truck. You can check the spec label location, photograph the failure, and confirm whether the door is binding against the stop or the frame. What you shouldn’t attempt: removing a pre-hung unit solo. The slab weighs 80 to 140 pounds depending on glass lite configuration, and the jamb is under compression from the rough opening. A dropped slab damages the fiberglass edge irreparably. The multipoint lockset also requires precise mortising; a wandering router bit destroys the lock stile. We’re background-checked, uniformed, and identified by license number before arrival, per Haven Clause 3. Call (786) 321-3319 and we’ll schedule the measured survey. The written price comes before any work starts.
FAQs
The fiberglass skin itself is indefinite, but the peripheral components have realistic service lives: weatherstrip five to seven years, sill end-seals eight to twelve years, multipoint hardware ten to fifteen years depending on cycle count. Call (786) 321-3319 for an assessment of what’s actually worn on your unit.
Skin delamination and sill pan failure require replacement; lockset misalignment and weatherstrip degradation can often be addressed with component-level work. We won’t quote a full install when a targeted repair is the honest call. Bring us a competitor’s written estimate and we’ll review it at no charge.
A slab replacement in a sound frame takes three to four hours; a full pre-hung with sidelites is a full day including trim and hardware adjustment. We don’t rush the dry-fit. Measure once, document it, then cut.
We carry weatherstrip profiles, sill components, and multipoint hardware for the Classic-Craft, Fiber-Classic, and Smooth-Star series. Full slab or pre-hung units are ordered to spec after the measured survey, with typical delivery in three to five business days. Same-day resolution applies to component failures we can match from stock.
Sightline Windows & Doors Kendall is an independent service provider and is not affiliated with Therma-Tru. We install and service Therma-Tru, PGT, CGI, CWS, and other manufacturer lines according to what the opening requires.
Call (786) 321-3319 to schedule your free estimate. You’ll receive the measured survey to keep, a written price before any work starts, and a documented photo record when the job is done.
Written by Sonia Raman, Owner, Sightline Windows & Doors Kendall at Sightline Windows & Doors Kendall, serving Kendall and nearby areas.










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