Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Fast, Reliable Roofing Company Across Castro Valley
Roofing work in Castro Valley is not a one-size-fits-all job. The town sits in a valley that traps summer heat above 100°F and still catches 20 to 25 inches of winter rain, while the eastern hills fall under a Very High Fire Severity Zone. That combination means your roof has to do two hard jobs at once: shed water through real storms and resist ember intrusion through fire season. Brennan Roofing builds for both. We are the Roofing Company that writes the full price down before work starts, sends background-checked uniformed technicians, and stands behind the job in writing for one full year. Call (361) 320-9467 and you will get a live person, not a queue.
Why Brennan Roofing Is Castro Valley’s Preferred Roofing Company Company
Castro Valley homeowners do not ask us to be the cheapest. They ask us to show up when we say we will, put the number on paper, and leave the roof right. That is The Garrison Standard, and it is the same on a six-square repair near the BART corridor as it is on a full replacement in the hills.
Our Castro Valley customers bring us repeat work because the process is boring in the best way. You get a written line-item quote before any work starts. The technician who shows up is background-checked and in uniform. If a repair fails within the year, we come back and make it right at no charge. That guarantee is written, not spoken.
Travis Oakley runs this operation to a code most roofers will not put in writing. He would rather lose a bid than fudge a fastening pattern or quote only the visible field and hope nobody opens the decking. That discipline is why we win the jobs where the homeowner has already been burned once.
Free Roof Estimate in Castro Valley
A Free Roof Estimate in Castro Valley starts with boots on the roof, not a drive-by from the street. We walk the field, the ridges, the valleys, the penetrations, and the flashing. We get into the attic where we can and check the decking from underneath. Then we give you a written number.
Every estimate from Brennan Roofing includes the full scope on paper. Decking replacement, underlayment, drip edge, flashing, vents, haul-away. If we see rotted decking at a valley, it goes in the quote. We do not hold it back as a surprise change order. The price you approve is the price on the contract, and anything that does change gets priced and signed off in writing before we touch it.
What we inspect on every estimate
We check the fastener pattern, especially on homes built between the 1950s and 1970s, when crews routinely used fewer nails than today’s wind code requires. We check the underlayment condition around every plumbing vent, skylight, and chimney. We check the decking for soft spots in the valleys, which is where Castro Valley’s winter rain finds its way in.
What the estimate includes
Materials matched to your roofline and fire zone, labor, tear-off and disposal, and a written workmanship guarantee. No allowance is left vague. If we allow for decking replacement, it is a dollar figure and a per-sheet rate, so you know the math before the crew arrives.
Roofing Contractor in Castro Valley
A Roofing Contractor in Castro Valley has to know the local building stock before making promises. The majority of homes here went up between the 1950s and 1970s. Many are on their second or third roof. The original fastening patterns rarely meet current wind load code, and the decking under those old shingles has had fifty or sixty years to absorb moisture.
As the contractor on those jobs, our crew works clean and tracks every change. When we tear off a roof, we do not hide what we find. The homeowner sees the decking before it gets covered. The contract includes allowances, and anything beyond the allowance gets a written price and your sign-off before the work proceeds.
Tear-off and decking repair
On older Castro Valley ranchers, we regularly replace decking at the eaves and through the valleys. The old underlayment fails around penetrations first. We run ice and water shield through every valley and set new flashing at every pipe, vent, and wall intersection. That is not an upgrade. It is the minimum to keep water out for the life of the shingle.
Fire-rated assemblies for the hills
Homes in the Palomares and Five Canyons areas sit in a Very High Fire Severity Zone. Insurance carriers increasingly require a Class A fire-rated assembly and ember-resistant vents just to renew the policy. We quote those assemblies as standard when the home is in the zone, and we document them for the insurer.
Trusted Brands We Service in Castro Valley
Brennan Roofing installs materials from GAF, Owens Corning, and Atlas, among other manufacturers. We carry architectural shingles, underlayment, and flashing components matched to the specs that Castro Valley inspectors and insurance carriers expect. If you need a heat-reflective color for the valley floor or a Class A assembly for the hills, we can write that into the same estimate. Parts for common Castro Valley roof types are in our local supply rotation, which shortens lead times on repairs and replacements.
Common Roofing Company Problems We See in Castro Valley Homes
- Fewer fasteners than modern code requires. Homes built in the 1950s and 60s were often nailed with four fasteners per shingle, not the six that current wind load standards demand. A strong wind event can peel entire sections off the decking.
- Rotted decking hidden under the visible field. The shingles look serviceable from the street, but the decking in the valleys and around penetrations has been soaking water for years. That is why our estimates include decking allowances instead of pretending the wood is fine.
- Non-fire-rated assemblies in the eastern hills. Homes in the Very High Fire Severity Zone sometimes have older roofs that do not meet the Class A standard insurers now require. We correct that with fire-rated assemblies and ember-resistant vents.
- Failed underlayment at penetrations. Plumbing vents, skylights, and chimneys are where original 1960s underlayment gives out first. Castro Valley’s winter rain is persistent enough to find those failures within a season or two.
Pricing for Roofing Company in Castro Valley, CA
A full roof replacement on a typical single-family Castro Valley home runs from $14,000 to $28,000 depending on square footage, tear-off difficulty, and fire-zone requirements. Roof repair work, like replacing flashing or a section of field shingles, typically lands between $450 and $1,800. A roof inspection runs $250 to $500, and we credit that fee toward the work if you hire us. Hillside homes with steep pitches, multiple dormers, skylights, or required Class A assemblies land higher. Valley floor ranchers with a simple roofline land lower. Call (361) 320-9467 for an exact written quote. The estimate is free.
We Also Serve Cities Near Castro Valley
Brennan Roofing runs crews from Castro Valley into San Lorenzo, San Leandro, Union City, and Dublin. The same Garrison Standard applies in every one of those towns: written pricing, uniformed technicians, and a full-year written guarantee.
Serving Castro Valley, CA - Our Local Coverage Area
We’re based in the Castro Valley 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 Roofing Company in Castro Valley
Because the original decking, underlayment, and fastening patterns on 1950s through 1970s homes rarely meet current code, and a contractor who quotes only the visible shingles is setting you up for change orders. Brennan Roofing writes decking allowances and per-sheet rates into the original contract, so the price already accounts for what the tear-off will expose. Call (361) 320-9467 for a written quote that includes those allowances.
If your home sits in the Very High Fire Severity Zone, which covers much of the Palomares and Five Canyons areas, your insurance carrier likely requires a Class A fire-rated assembly with ember-resistant vents. We quote that assembly as standard for homes in the zone, and we document it for your insurer. Call (361) 320-9467 to confirm whether your address falls inside the zone.
We recommend lighter-colored architectural shingles with a solar-reflective rating where the home is on the valley floor, because Castro Valley summers routinely pass 100°F and the UV accelerates shingle aging. Heat reflectivity and fire resistance go into the same estimate, because both matter on the same roof. Call (361) 320-9467 and we will show you the material options and their reflectivity ratings.
A square is 100 square feet of roof surface. Roofing materials are priced per square, and labor is estimated against the total number of squares. Knowing your roof’s square count lets you compare bids line for line, which is why our written quotes break the work out that way. Call (361) 320-9467 for a free estimate that shows the math.
Yes, if the fastening pattern meets current wind code and the underlayment and flashing are installed correctly. That is why we correct original 1950s and 60s fastener counts instead of nailing over them, and why we run ice and water shield through every valley. The work is covered by the 365-Day Done Right Promise in writing. Call (361) 320-9467 to schedule the free estimate.
Call Brennan Roofing at (361) 320-9467 for a free, written roofing estimate in Castro Valley. Travis Oakley and the crew will show up on time, put the full price in your hand before any work starts, and leave the roof done right.
Written by Travis Oakley, Owner at Brennan Roofing, serving Castro Valley under The Garrison Standard.






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