Kitchen remodeling
Bathroom remodeling
Home additions & ADU
Roofing
Windows & doors
Driveway & pavers
FenceFree written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Therma-Tru Construction in Highland, CA | Stallion Contractors
We install, repair, and replace Therma-Tru door systems across Highland, and the single factor that changes the work here is fire-hazard review: most door swaps in the foothill-edge lots trigger San Bernardino County WUI requirements that a flatland contractor never sees. That shapes everything from the sill pan we specify to the weatherstripping we use. Stallion Contractors is an independent Highland General Contractor and Therma-Tru service provider serving the 92346 zip code. Call (855) 600-3192 for a free estimate on any Therma-Tru door, frame, or glass insert.

Why Highland Residents Choose Us for Therma-Tru Service
We’ve pulled enough Therma-Tru slabs out of Highland doorways to know which ones survive this climate and which ones don’t. Our owner, Ruben Montoya, grew up in Colton and trained at San Bernardino Valley College, so the foothill sun, the Santa Ana wind, and the county’s fire-hazard requirements aren’t abstract to us. They’re the conditions we work in every week.
When you call us about a Therma-Tru door that’s binding, chalked, or leaking, we don’t start by selling you a replacement. We measure the slab, check the frame for rot, test the hinges, and look at the sill. If the door can be corrected with genuine Therma-Tru replacement hardware, a new sweep, or a re-sealed threshold, that’s what we recommend. If the frame is compromised or the slab is delaminated, we’ll tell you that too, and we’ll show you why. That’s what independent service should look like. For the full scope of our Therma-Tru work, see our Therma-Tru sales & service page.
Styles & brands we work with







Common Therma-Tru Construction Problems We Solve in Highland
Highland’s specific mix of intense UV, dry heat, Santa Ana wind events, and foothill drainage creates a distinct failure pattern in Therma-Tru doors. These are the five we see most:
- Gel-coat chalking and slab face cracking on west-facing elevations. In Highland, the afternoon sun hits the west side of a house hard, especially during summer when temperatures sit above 100 degrees for weeks. Therma-Tru Fiber-Classic slabs with older finishes craze and chalk faster than doors on shaded north walls.
- Warped or binding slabs from thermal cycling. Highland nights in the foothills cool down fast, even after hot days. A fiberglass door slab expanding against its frame all afternoon and contracting at night gradually distorts, and the first symptom homeowners notice is a door that won’t latch cleanly in July.
- Failed weatherstripping and sill seals letting in wind-driven dust and embers. Santa Ana events push fine particulate through the smallest gaps. On lots in or near the wildland-urban interface, that same wind can carry embers. A worn Therma-Tru sweep isn’t just an air leak here. It’s a fire-hardening failure.
- Water intrusion and rot at wood sub-sills and threshold pans. Highland’s foothill lots slope, and winter rain funnels toward entries on the low side of older houses. If the original sub-sill under a Therma-Tru door was wood, it’s often the first thing to go.
- Sagging hinges from repeated door use plus slab weight. Therma-Tru entry slabs are heavy. On some of Highland’s 1970s-90s tract homes, the original hinge screws were short and the jamb was minimally shimmed. After twenty or thirty years, the hinge side drops and the latch side scrapes.
Therma-Tru Service in Highland: What Local Conditions Mean for Your Equipment
Here’s the thing most door contractors from the flatlands miss: in Highland’s foothill-edge neighborhoods, an exterior door replacement often pulls a San Bernardino County fire-hazard review that a simple over-the-counter permit elsewhere never triggers. Once that review starts, the county looks at the whole opening, not just the slab. The door’s ember-resistant sealing, the threshold assembly, the gap tolerances at the sides and bottom, and the materials in the sill pan all become inspection items. A door that would pass with standard Therma-Tru in Redlands flatland can fail in Highland if the weatherstripping is worn or the sill pan isn’t rated for the assembly.
That changes the job. We don’t swap a slab and walk away in Highland. We check the entire opening against what the county will actually inspect, then correct what’s deficient before the inspector shows up. It’s the difference between a permit that closes in one visit and one that bounces back with corrections.
Therma-Tru Models & Products We Service in Highland
We work on the full Therma-Tru lineup installed across Highland’s housing stock:
- Fiber-Classic and Fiber-Classic Mahogany entry door collections, including sun-damaged slab refinishing or replacement
- Smooth-Star fiberglass exterior and patio doors, including slab-only swaps into sound frames
- Profinity and Traditions fiberglass entry systems with their hinge and sill hardware
- Camden, Saratoga, and Harborview decorative glass and lite inserts, including glass-only replacement
We use genuine Therma-Tru replacement glass, sills, sweeps, and hinge hardware when the slab and frame are sound, because aftermarket parts don’t hold the same weather and fire-resistance rating. For Highland specifically, we keep common Therma-Tru sweeps, sill caps, and hinge sets on hand so we’re not waiting on a distributor for basic hardware. When the frame is rotted or the slab is delaminated, we recommend full replacement and will quote both options honestly.
See the difference
Before
After
Before
After
Before
AfterTherma-Tru Service Pricing in Highland
What you’ll pay depends on whether we’re replacing glass, rebuilding a sill, or replacing the whole opening as part of a larger project. Here are the realistic ranges:

| Service | Highland Price Range |
|---|---|
| Window Replacement (Therma-Tru door glass or exterior opening work) | $4,500 – $15,000 |
| Home Addition (exterior door and opening integration) | $45,000 – $130,000 |
| Garage Conversion (entry door and exterior opening work) | $30,000 – $80,000 |
Cost drivers in Highland are specific: WUI hardware upgrades, sill pan replacement on rotted sub-sills, and full-frame rebuilds on older foothill homes all move the number. We don’t give vague estimates. You’ll get a written, line-item quote before work starts, so you can see exactly where the money goes. Call (855) 600-3192 and we’ll schedule a free estimate at your Highland home.
Serving Highland, CA — Our Local Coverage Area
We’re based in the Highland area and know this community well, and we also provide Therma-Tru service in Loma Linda. Use the map below to see our full service coverage — if you’re nearby, we can almost certainly help.
FAQs – Therma-Tru Construction in Highland
Yes, if the frame is structurally sound and the jamb hasn’t shifted or rotted. We replace Fiber-Classic and Smooth-Star slabs into existing frames regularly, but we won’t do it if the frame won’t hold proper reveals. In Highland, the WUI review often requires us to correct frame sealing at the same time, even when only the slab is being replaced. Call (855) 600-3192 and we’ll inspect the opening before you spend a dollar.
It depends on your specific lot and its proximity to the wildland-urban interface boundary. Many foothill-edge parcels in Highland’s 92346 zip code do trigger review, and it’s not something a contractor can wave away. We handle the review as part of the permit package and correct the opening to pass on the first inspection. Give us a call at (855) 600-3192 and we’ll check your address against current county mapping before we quote.
Intense UV exposure and dry inland heat have broken down the gel coat. This is common on west-facing and south-facing doors in Highland, where summer sun hits a slab for six-plus hours a day. Once the finish is chalked through, refinishing is usually temporary. We can advise whether a re-coat will hold or whether the slab needs replacement based on how far the degradation has gone.
Usually it’s the slab responding to thermal cycling: expanding during hot Highland afternoons and not fully returning to its original dimensions. Sometimes it’s frame movement from settling foothill soil. We diagnose the difference with a straight edge and a gap gauge rather than guessing, because the fix for each is different. Call (855) 600-3192 and we’ll tell you which one you have.
Yes. We use Therma-Tru’s own replacement glass, sweeps, sills, and hinge hardware whenever the slab and frame remain intact. Genuine parts preserve the door’s weather rating and its performance in a WUI-reviewed opening, which is exactly what Highland’s fire-hazard process expects. Aftermarket parts don’t carry the same certainty, so we don’t use them on Therma-Tru doors.
Service Areas Near Highland
Our crews cover Highland and the surrounding foothill and valley communities, including Highland service area details for the full map. We also run Therma-Tru service into Therma-Tru service in San Bernardino, Therma-Tru service in Rialto, Colton, Bloomington, Mentone, San Antonio Heights, Loma Linda, and Redlands. If your project sits anywhere in that reach, we can quote it.
Book Your Therma-Tru Service in Highland Today
If your Therma-Tru door is chalked, binding, leaking, or flagged by a county fire-hazard review, call (855) 600-3192 now. We’ll schedule a free estimate at your Highland home and give you a written, line-item quote. No pressure, no showroom pitch. Just a straight answer on what the door needs and what it costs.
Written by Ruben Montoya, Owner at Stallion Contractors, serving Highland and the surrounding Inland Empire communities.