Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Mr-Glass Home Additions & ADU: The West Covina Owner’s Guide
If you own a Mr-Glass home addition or ADU in West Covina and a component has failed, we can match the part and install it. Installed replacement work for Mr-Glass home additions and ADU systems in West Covina typically runs $45,000 to $130,000 depending on scope, structural condition, and finish level. Most owners discover a problem the same way: a door binds in its frame, a window fogs at the edges, or the HVAC in the ADU starts cycling more often than it used to. What begins as a small annoyance usually traces back to a specific part, and that part is almost always replaceable without tearing the whole structure apart.
We stock Mr-Glass-compatible components on our trucks and install them across West Covina, from the older neighborhoods south of the 10 to the newer builds up near the hills. If you’re not sure what failed, we’ll identify it during the estimate visit.
Key takeaways:
- Mr-Glass home addition and ADU part replacements in West Covina typically cost $45,000 to $130,000 installed.
- We carry OEM-spec and quality aftermarket equivalents for Mr-Glass systems.
- The estimate is free, the price is written, and the work is backed for 365 days from completion.
- Call (707) 760-7579 and a live person answers, any hour of any day.
What usually fails first
Most Mr-Glass additions and ADUs we see in West Covina were built as accessory structures, which means they sit on separate slabs or pier systems. The first components to fail are almost always the ones exposed to the most movement: threshold seals, door alignment hardware, window flashing, and the kick-out flashing where the ADU roof meets the main house. The San Gabriel Valley’s heat cycles work on expansion joints harder than coastal air does, and we replace more failed flashing and seal assemblies in West Covina than in any other part of our service area.
Which Mr-Glass Models This Applies To
Mr-Glass home additions and ADU systems use a mix of standard residential components and a few proprietary trim profiles. The compatibility question comes down to measurement, not model year. Mr-Glass door and window openings are typically framed to standard rough-opening sizes, which means a quality aftermarket part fits as well as the OEM piece, provided the flange profile matches.
Here’s the gotcha most people miss: Mr-Glass corner trim and sill profiles use a slightly deeper reveal than off-the-shelf box-store trim. If you buy a generic replacement for a Mr-Glass addition door sill or corner board, it will sit proud of the existing trim line. We keep the correct reveal-depth stock on hand for West Covina jobs, and we verify the profile before we order anything. For most parts, an OEM-spec or properly matched aftermarket equivalent performs identically. For weather-exposed parts like door pans and window flashing, we recommend staying with the OEM profile because the seal geometry is specific.
Identification is straightforward. Look for the Mr-Glass tag on the inside of the door jamb, on the window sash edge, or on the ADU subpanel label. If the tag is gone, measure the rough opening and the trim reveal, and we can match it from there.
Styles & brands we work with
Signs Your Mr-Glass Home Additions & ADU Is Failing
- Door binds or drags at the threshold. This usually means the threshold assembly has settled or the hinge-side shim pack has compressed. The underlying problem is often the sill flashing degrading under the door, allowing moisture to swell the subfloor.
- Fog between window panes. A failed insulated glass unit (IGU) means the seal has opened. In West Covina’s summer heat, a breached IGU can fail within one season. The fix is a replacement sash or a new IGU, not a whole window replacement.
- Water staining at the top corner of a wall. On Mr-Glass additions, this almost always traces to the kick-out flashing where the addition roof intersects the main structure. When that flashing pulls away, water runs behind the siding and shows up at the interior corner.
- HVAC runs constantly but the ADU doesn’t hold temperature. This points to a failed duct connection or a split in the flex duct in the crawl space or attic chase. The part itself is inexpensive; the labor to access it in a compact ADU is where the cost lives.
- Siding buckles or paint blisters on the south or west wall. West Covina’s afternoon sun is aggressive on wall assemblies. When the WRB (weather-resistant barrier) behind the siding fails, the siding moves and the paint fails in a specific pattern: blisters low, peel high.
See the difference
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After
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AfterReplacement Cost & What’s Included
For a Mr-Glass home addition or ADU part replacement in West Covina, installed pricing runs $45,000 to $130,000. That range covers everything from a single-system repair on a small addition to a full-component overhaul on a larger ADU with structural correction. The spread comes down to three things: access, existing damage behind the failed part, and whether the repair requires matching custom finishes.
Every estimate includes the part, labor, disposal, and a written line-item scope. No verbal number, no change-order creep. If we open the wall and find more than we expected, we stop, show you what we found, and put the new number in writing before we keep going. The work is covered by the 365-Day Done Right Promise: if anything we installed fails within a year of completion, we return and fix it at no charge.
Here’s what the range typically covers:
- $45,000 – $80,000: Single-system replacement on a smaller Mr-Glass addition, such as a full door assembly, window IGU set, or flashing package with localized drywall repair.
- $80,000 – $105,000: Multi-system work on a larger addition or ADU, including structural shimming, door and window package replacement, and re-flashing the roof-to-wall intersections.
- $105,000 – $130,000: Full-component overhaul with structural correction, insulation remediation, and complete exterior envelope repair on a large ADU.
Call (707) 760-7579 for a written estimate on your specific Mr-Glass addition or ADU. You should know what you’re getting before we ever pick up a tool.
DIY or Call Us?
Some checks are safe for any homeowner. You can inspect the threshold for obvious gaps, look for water staining at wall corners, and verify that your ADU’s subpanel label is visible. Those observations help you describe the problem when you call.
What we don’t recommend is pulling trim, cutting into wall assemblies, or working on the electrical side of an ADU system. Mr-Glass additions use high-tension door hardware in some configurations, and a spring-loaded closer under load can release fast. Electrical work in an ADU subpanel carries shock risk, and cutting into a wall without knowing where the wiring runs is a real hazard. A trained professional with the right tools and the right trim profiles will get it done without turning a part replacement into a bigger repair. If the part is structural, weather-exposed, or electrical, call us at (707) 760-7579 and we’ll handle it.
FAQs
Most Mr-Glass addition and ADU components last 15 to 20 years in West Covina’s climate, though sun-exposed flashing and seal assemblies on south and west walls often fail in 8 to 12 years. Regular inspection of the kick-out flashing and threshold seals extends the life of everything behind them. Call (707) 760-7579 if you’re seeing early signs of wear.
Some parts can be repaired: a failing window seal can sometimes be re-glazed, and a shifted door can often be re-shimmed without replacing the frame. But weather-exposed seals and flashing assemblies usually need replacement once they’ve failed, because the damage is material fatigue, not a single event. We’ll tell you honestly which one applies during the estimate.
Most single-system replacements on a Mr-Glass addition or ADU take one to three days, depending on access and what we find behind the failed part. Structural corrections or full-envelope work can take one to two weeks. You’ll get a written timeline with your estimate.
We stock the most common Mr-Glass-compatible parts on our trucks: door thresholds, window IGU units in standard sizes, flashing profiles, and Door pans. For less common sizes or custom trim profiles, we order from our local supplier and typically have the part within a week. We’ll confirm availability before we schedule the work.
No. The price we put in writing before the work starts is the price you pay, unless we uncover hidden damage that requires additional scope. If that happens, we stop, show you what we found, and put the new number in writing before any additional work begins. No surprise invoices, ever.
Written by Isaac Pruett, Owner, Mason Remodeling Co West Covina at Mason Remodeling Co West Covina, serving West Covina and nearby areas.
