Architectural shingles
Metal roofing
Tile roofing
GAF
Owens Corning
Flat & low-slopeFree roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Fast, Reliable Roof Repair Across Monrovia
Roof repair in Monrovia most often means one thing: a leak above a 1920s bungalow or a cracked tile on a north-side street where the canyon wind has been working on the slope for decades. We handle it the way it needs to be handled here. You call (866) 850-2496, we come out and open the problem up, then we tell you exactly what we found and what it costs before anything gets touched.

Windmill Roof Repair serves both 91016 and 91017, and we know the difference between a Mayflower Village stucco roof and a Spanish Colonial tile roof off Foothill Boulevard. Ruben Ochoa leads the crew, and he’s the one making the call on whether a repair is the right move or a replacement actually saves you money long-term. No pressure either way. You get the straight answer, the written estimate, and the choice.
Why Windmill Roof Repair Is Monrovia’s Preferred Roof Repair Company
We don’t rope you into one brand. Windmill works with seven shingle manufacturers, including GAF, CertainTeed, and Owens Corning, so the recommendation matches your roof, not our inventory. That matters in a city like Monrovia where housing stock ranges from Craftsman bungalows with cedar shake to mid-century ranch homes with concrete tile. A roofer locked into a single brand will try to make every roof fit that product. We don’t have that problem.
Our reputation here comes from honest scoping. Homeowners off Myrtle Avenue and in the neighborhoods above Hillcrest Boulevard call us because we’ll repair when we can and tell you straight when replacement is actually the better financial call. That’s the repair-when-you-can, replace-when-you-must approach. No scare tactics about a roof that has five good years left.
We reach Monrovia quickly from our Orange, CA base, and we’ll have eyes on your roof within a day or two of your call. Every estimate is free and written, line by line, so nothing gets buried in contractor shorthand. Ruben reviews every estimate before it goes out. If you have questions about a line item, you get them answered before you sign.
Styles & brands we work with






Metal Roof Repair in Monrovia
Metal Roof Repair in Monrovia is a specialty of ours, and it usually comes up on the city’s older commercial buildings or on the handful of newer standing-seam residential roofs near the foothills above Grand Avenue. Metal roofs handle the foothill sun better than most materials, but they still fail at seams, fasteners, and penetrations, especially after years of Santa Ana wind working the panels loose. A typical metal repair here runs $450 to $1,200 depending on the number of seams involved and the flashing condition.
Seam and Fastener Repair
Wind-driven rain from the canyons finds its way into loosened fasteners before you ever see a stain on the ceiling. We replace failed gaskets, re-secure panels, and re-seal seams with materials rated for the heat load Monrovia roofs carry in July and August.
Penetration and Flashing Work
Exhaust vents, skylights, and pipe boots on metal roofs in the 91016 zip code fail at the joints first. We’ll strip the old sealant, inspect the flashing for cracks, and install new boots and counterflashing that actually shed water instead of trapping it.
Commercial Roof Repair in Monrovia
Commercial Roof Repair in Monrovia covers the flat and low-slope buildings along Myrtle Avenue, Huntington Drive, and the older industrial stretch near the 210. These are mostly modified bitumen or built-up roofs installed decades ago, and they fail in predictable ways: split seams, ponding water, and dried-out flashing around curbs and HVAC units. Repair pricing for a typical Monrovia commercial roof runs $650 to $2,400 depending on the number of penetrations and the condition of the existing membrane.
Flat Roof Patch and Seam Work
When ponding water sits on a Monrovia flat roof after winter rain, the real question is whether the roof is draining properly or whether the membrane has worn through at the low point. We patch, re-seam, and re-slope where possible so the water stops collecting in the first place.

Parapet and Curb Flashing Repair
Parapet walls and rooftop curbs are the first places wind-driven rain gets into a commercial building. We rebuild failed flashing, replace cracked sealant, and re-attach metal counterflashing using fasteners and sealants that hold up to the foothill sun.
Trusted Brands We Service in Monrovia
We carry materials and match profiles for GAF, CertainTeed, Owens Corning, IKO, and more, which means we can usually source exactly what your existing roof uses. A repair on a CertainTeed Presidential Shake roof in Mayflower Village should not end up with a mismatched patch from whatever shingle the roofer had in the truck. We stock local supply runs for Monrovia jobs so the material matches, and we’ll never push a full replacement when a targeted repair is the right call. Seven brands, one crew. The right material for your roof, not ours.
See the difference
Before
After
Before
After
Before
AfterCommon Roof Repair Problems We See in Monrovia Homes
- Cracked clay tiles on north-side streets. Homes above Foothill Boulevard and along Canyon Crest Drive take decades of canyon wind and direct sun. Tiles crack from thermal stress and wind-driven debris, but the leak often starts in the underlayment long before the tile gives out.
- Original skip sheathing from the 1920s through 1940s. Many Monrovia homes still have open-gap sheathing boards under their tile. Repair estimates that assume modern plywood decking will be wrong, and underlayment adhered to skip sheathing fails differently than on solid decking.
- Undersized valley and penetration flashing. Santa Ana winds push water uphill at the valleys and around pipe boots. Flashing that worked fine for a coastal roof often gives out on a Monrovia roof facing the San Gabriels.
- Sun-baked fascia and soffit rot. When original underlayment behind clay tile stops shedding water, winter rain pools at the eaves. The fascia rots from the inside out. By the time you see paint peeling, the framing underneath often needs repair too.
Pricing for Roof Repair in Monrovia, CA
Roof repair pricing in Monrovia runs on a range that reflects what we find once we open the problem up. Minor leak repairs at a pipe boot or a section of flashing typically run $350 to $650. Valley repairs with new underlayment and flashing usually fall between $800 and $1,800. Full roof repairs involving original skip sheathing, rewiring, and structural work can push $3,000 to $6,000 or more, but those are the exception, not the norm. We write allowances into every contract for the unknowns, and Ruben personally approves any change before we touch it. You get a written, line-by-line estimate at no charge before you commit to anything. Call (866) 850-2496 to schedule yours.
We Also Serve Cities Near Monrovia
Our service area covers homes and commercial properties across the San Gabriel Valley. We repair roofs in Monrovia, and we regularly work in Mayflower Village, Duarte, Bradbury, and Arcadia as well. If you’re in one of these nearby cities, our Roof Repair team covers the same brand-neutral approach and the same written, line-item estimates.
Serving Monrovia, CA — Our Local Coverage Area
We’re based in the Monrovia 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 About Roof Repair in Monrovia
Not necessarily. If the skip sheathing is still sound and the underlayment is intact, we can repair the visible tile damage and leave the sheathing alone. But when the underlayment underneath has failed, us on the north side of Monrovia find that the only correct fix is to remove the tile in the affected area, replace the underlayment, and address any sheathing boards that have rotted or split. We’ll show you photos before we do anything. Call (866) 850-2496 for a free inspection.
We flag it immediately, we photograph it, and we write a change order with a specific price before any electrical work happens. On a 1928 Spanish Colonial off North Canyon Drive, our crew found knob-and-tube wiring running through the attic during a valley repair. The homeowner approved an upgrade, we handled the rewiring as part of the job, and the final invoice matched the revised contract. No mid-job price shock. If we find old wiring during your repair, you’ll hear about it from us before the electrician even gets scheduled.
We service and match materials across seven shingle brands, including GAF, CertainTeed, Owens Corning, IKO, Atlas, Tamko, and Boral. That broad lineup matters in Monrovia because the original tile, shake, and composite roofs across the city use a wide mix of profiles. We don’t have a preferred manufacturer we’re trying to push. Call (866) 850-2496 and we’ll match your existing roof.
Most targeted repairs, like replacing a few cracked tiles or re-flashing a single penetration, do not require a permit in Monrovia. But if we’re opening up a large section and replacing underlayment on a historic home, the city may require a permit, and that can trigger code upgrades for electrical or structural conditions we uncover. We handle the permit process for you and write any code-required work into a revised contract before proceeding. You approve everything in writing first.
You ask each contractor to break the quote into line items: materials, labor, disposal, and any allowance for unknowns. A square is simply 100 square feet of roof area. If one Monrovia quote gives a per-square price and another gives a flat number, ask the flat-number contractor to show their square calculation. We write every estimate line by line with the square footage shown, so you can compare our numbers directly against anyone else’s. Estimates are free.
Written by Ruben Ochoa, Owner at Windmill Roof Repair, serving Monrovia and the San Gabriel Valley.