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Therma-Tru Construction in Half Moon Bay, CA | Seaside Contractors
We provide independent Therma-Tru installation and repair across Half Moon Bay, from Frenchman’s Creek to Miramar and up into the hills. The one thing that makes our Therma-Tru work different here is that we build every door opening for the salt fog first and the aesthetics second. If you’re dealing with a sticking slab, peeling finish, or a frame that’s rotting at the sill, call us at (833) 589-8103. We’re Seaside Contractors, and we’ve been installing and servicing Therma-Tru door systems on this coast long enough to know exactly where they fail.
Why Half Moon Bay Residents Choose Us for Therma-Tru Service
We know Therma-Tru’s product lines the way a mechanic knows a specific engine family. Smooth-Star, Classic-Craft, Fiber-Classic, Benchmark – each has its own failure pattern in marine air, and each needs different detailing at the threshold. Glen Sorrento, our owner, studied building construction technology at College of San Mateo and has spent more than two decades working Peninsula projects, from lagoon-side homes in Foster City to bluff-top remodels here on the coast. That background means we don’t guess at what’s behind a sticking door. We pull the casing, look at the flashing, check the sill pan, and tell you what’s actually happening.
We’re an independent contractor, not a Therma-Tru dealer or authorized service center. Our credibility comes from coastal installs and callbacks, not a badge. And because we’re a full-scope general contractor, we can handle what’s behind the door too – the rotted framing, the failed waterproofing, the siding that’s been wicking moisture into the jamb. One contractor, every trade.
Styles & brands we work with







Common Therma-Tru Construction Problems We Solve in Half Moon Bay
- Bottom-rail blistering and delamination on fiberglass slabs. The Smooth-Star and Fiber-Classic lines use a fiberglass skin over a core. When the threshold seal fails, fog-driven moisture wicks up into the bottom rail and the skin separates from the core. We see this most on west-facing entries that take the afternoon onshore wind, where the door stays wet for hours after the fog burns off. Patch jobs don’t hold here – the panel needs replacement and the threshold needs to be re-detailed.
- Premature finish chalk and peel. Factory Therma-Tru paint and stain finishes fail years earlier in Half Moon Bay than they do inland. The combination of salt spray, UV exposure through the fog, and constant moisture cycling breaks down the factory topcoat. South- and west-facing doors are the worst. We reprep and refinish with marine-grade coatings, but if the finish has failed across the whole slab, replacement makes more sense than chasing it.
- Corroded and seized hinges, strike plates, and sill screws. Standard plated hardware does not survive this coastal environment. We regularly find hinge pins fused to the leaves and strike screws that snap off in the jamb. The fix is straightforward: stainless or marine-grade fasteners and upgraded hinges, set into a jamb that’s been checked for rot first. No point putting good hardware into soft wood.
- Rot at the sill and threshold corners. This is the Half Moon Bay signature failure. Wind-driven rain pools at the threshold corners, and if the original installer never ran continuous pan flashing or sloped the sill properly, the jamb legs and sub-sill soak up water every storm season. By the time the door sticks, the frame is often already compromised. We cut out the rot, rebuild the jamb leg with treated stock, and set a new adjustable sill that drains properly.
- Sagging slabs from failed hinges in marine air. A Therma-Tru fiberglass door is lighter than solid wood but still heavy enough that worn or corroded hinges let the slab drop. You’ll see the door dragging on the threshold or latching high. We replace hinge sets with coastal-rated hardware and re-shim the jamb so the reveal is even and the weatherstrip seals cleanly.
Therma-Tru Service in Half Moon Bay: What Local Conditions Mean for Your Equipment
Here’s what we know from years of installs on this coast: because Half Moon Bay doors sit in near-constant marine fog and salt spray, the exposure face is almost always the west-facing entry that takes the afternoon onshore wind. That’s the side inland San Mateo and Redwood City installs never have to defend at this level. Their doors get wet during storms and dry out. Yours gets wet every single afternoon from May through August, even when it isn’t raining. So we detail thresholds and flashings for continuous wetting rather than occasional storms. That means stainless fasteners as the default, not an upgrade. Continuous pan flashing under every exterior door. Adjustable sills with positive drainage to the exterior. And a real look at the substrate before the new door goes in, because if the rough opening has been absorbing fog moisture for a decade, a new slab is just a lid on a problem. This is also why coastal permit review matters here – the inspectors in Half Moon Bay expect salt-tolerant, wind-rated detailing on exposed openings, and they will call out hardware and flashing that would pass without comment over the hill. If you’re not building for that review, you’re doing it twice.
On a bluff-side home in Therma-Tru in Moss Beach territory off the coastal hills, we pulled a Fiber-Classic entry whose bottom rail had delaminated and whose plated hinges were frozen solid from years of salt fog. We replaced the slab with a Smooth-Star fiberglass door, rebuilt the rotted jamb leg, and set a new adjustable sill with stainless fasteners and continuous pan flashing. The homeowner now has a door that seals against wind-driven rain instead of swelling and sticking every fog season.
Therma-Tru Models & Products We Service in Half Moon Bay
We install and service the full Therma-Tru residential lineup, including the Smooth-Star fiberglass entry doors, the Classic-Craft American Style collection, the Fiber-Classic series, and the Benchmark fiberglass line. When the frame is sound, we use genuine Therma-Tru OEM slabs, sills, sweeps, and hinge sets. We also spec stainless or marine-grade fasteners and upgraded sills regardless of brand, because the factory hardware simply doesn’t last in this salt air. We keep common weatherstripping profiles, sweep seals, and hinge sets on hand for faster turnaround on the coast, and we can order OEM slabs and glass inserts with a clear lead time. And we’ll be straight with you: if the core is saturated, the jamb is rotted, or the finish is failing across the slab, we recommend replacement rather than patch. Coastal doors reach the point of no return faster than inland ones, and you don’t want to pay for a repair that buys you one more fog season.
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AfterTherma-Tru Service Pricing in Half Moon Bay
Most El Granada Therma-Tru service and Half Moon Bay work falls into one of these three scopes, and the numbers below reflect what we typically see on the coast.
| Scope | Typical Range |
|---|---|
| Window replacement (often paired with door work) | $4,500 – $15,000 |
| Impact window installation (coastal wind-rated) | $8,000 – $25,000 |
| Home addition (entry plus framing and finish work) | $45,000 – $130,000 |
What drives the cost on a Therma-Tru door job here is the condition of the rough opening – if the jamb is rotted or the sill pan was never flashed, the repair is more invasive than a slab swap. A free estimate includes pulling the interior casing, checking the substrate, and giving you a written line-item quote so you know exactly what you’re paying for. Call (833) 589-8103 to get on the schedule.
Serving Half Moon Bay, CA — Our Local Coverage Area
We’re based in the Half Moon Bay area and know this community well. Use the map below to see our service coverage — if you’re nearby, we can almost certainly help.
FAQs – Therma-Tru Construction in Half Moon Bay
Will a Therma-Tru fiberglass door hold up to Half Moon Bay’s salt fog better than wood? Yes, a Therma-Tru fiberglass door will outperform wood in this marine environment because the fiberglass skin doesn’t absorb moisture or rot the way wood stiles and rails do. But it still needs coastal detailing – stainless hardware, continuous flashing, and a properly sloped sill – or the frame around it will fail even if the slab doesn’t. Call (833) 589-8103 if you want us to assess your existing setup.
Why is my Therma-Tru door finish peeling so fast here? The factory finish on Therma-Tru doors, especially on south- and west-facing exposures, chalks and peels quickly in Half Moon Bay because of constant salt spray, UV cycling through the fog, and moisture that never fully dries. If the peel is isolated, we can prep and refinish. If it’s across the whole slab, replacement is usually the better call. Call (833) 589-8103 for an honest assessment – estimates are free.
Does coastal permit review in Half Moon Bay affect a door or window replacement? Yes, door and window replacements on existing openings typically go through the Half Moon Bay building department, and coastal zone projects can add extra review time depending on the location and scope. We handle the permit paperwork and build to the detailing the inspectors expect, which saves you from failed inspections and re-work.
My Therma-Tru door sticks and the lock is hard to turn – is that the door or the frame? It’s usually both, working together. In this climate, the frame absorbs moisture and swells while the hinges corrode and let the slab sag, so the door drags and the latch binds. We fix the underlying issue – replacing the hinges, re-shimming the jamb, and checking for rot – rather than planing the slab, which just masks the problem.
Can you match a new Therma-Tru entry to the existing door style on my home? Yes, the Therma-Tru Classic-Craft and Smooth-Star lines come in a range of panel profiles, glass options, and finishes that let us match or complement the existing architecture of a Half Moon Bay home, whether it’s a 1950s coastal cottage or a newer custom build. Call (833) 589-8103 to walk through the options with our team.
Service Areas Near Half Moon Bay
Beyond Half Moon Bay, we serve the surrounding San Mateo County coast and the nearby communities of El Granada, Moss Beach, Montara, and Princeton-by-the-Sea. We also provide Therma-Tru service in Highlands-Baywood Park and Therma-Tru service in San Mateo. If you’re on the coast side of the hill, you’re in our service area. We cover the 94019 ZIP and the roads that feed it.
Book Your Therma-Tru Service in Half Moon Bay Today
If your Therma-Tru door is sticking, peeling, or letting fog moisture into the frame, we’ll come out, pull the casing, and tell you what’s actually happening. No guesswork, no pressure. Call (833) 589-8103 to schedule your free estimate and get on the calendar.
Written by Glen Sorrento, Owner at Seaside Contractors, serving Half Moon Bay and the San Mateo County coast.