Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Before
After
Before
After
Before
AfterFast, Reliable Roof Installation Across Half Moon Bay
A new roof in Half Moon Bay runs $14,000 to $38,000 for most single-family homes, with standing seam metal starting around $28,000 and architectural shingle tear-offs typically landing between $14,000 and $22,000 depending on decking condition. Those numbers reflect what we actually see on coastal properties here, where salt air and fog change the math on materials. That’s why a written price comes before any work starts on your Half Moon Bay roof, every time. Call (743) 200-8347 to schedule a free estimate with Mercer Roofing.
Why Mercer Roofing Is Half Moon Bay’s Preferred Roof Installation Company
Half Moon Bay homeowners tend to ask the same questions before they sign anything. Who is actually showing up at the door? What happens if the decking is rotten underneath? Will the price change once the old shingles come off? We answer all three the same way: before any technician arrives, we send you their name and photo. They badged in with photo ID at your door, uniformed and background-checked under the Threshold Verified standard. And the price is in writing before the first nail is driven, with no open-ended surprises.
Grant Whitlock leads our crew, and he has spent enough time on roofs between the Pillar Point bluffs and the flats off Highway 1 to know what this climate does to a roof. That local knowledge shows up in how we specify materials, how we write allowances into contracts, and how we handle the inevitable discoveries that come with opening up a 1960s or 1970s roof. The 365-Day Done Right Promise applies to every installation: if it is not right within a year, we make it right, in writing.
Our reviews from Half Moon Bay customers consistently mention two things: the technician introduced themselves by name at the door, and the final invoice matched the written estimate. For homeowners who are often home alone or have young kids, that matters more than a flashy website. Roof Installation is not a side service for us, it is what we do every week along the San Mateo coast.
Standing Seam Metal Roof in Half Moon Bay
Standing Seam Metal Roof installation in Half Moon Bay is the strongest answer to the two forces that destroy roofs here: salt-laden marine air and wind-driven rain that arrives nearly horizontal in winter storms. The vertical seam design and concealed fasteners leave no exposed rubber washers or screw heads for salt to attack, and the panel profile sheds water faster than any shingle overlap can. In Half Moon Bay, a standing seam metal roof typically runs $28,000 to $42,000 for an average single-family home, including tear-off of the old roof.
The coastal-bluff properties near Pillar Point and the ocean-facing streets off Kelly Avenue see the worst of it. We have measured standard galvanized drip edge on those homes with visible rust pitting in under four years. On every oceanside standing seam install, Mercer Roofing specifies stainless steel flashing, stainless fasteners, and aluminum or Galvalume panels rated for marine environments. That is not an upsell. It is the only way a manufacturer’s warranty holds in this air.
Marine-Grade Fastening and Flashings
Standard panel clips and seam fasteners are zinc-coated steel. That coating fails fast within a quarter mile of the open Pacific. On a recent install near Pillar Point, our crew pulled galvanized drip edge from a 2009 roof that had rusted through at every miter joint. We replace that entire metal layer with Type 316 stainless or powder-coated aluminum as a matter of course, and we write it into the estimate up front so the price is not a surprise later.
Fog-Damp Attics and Ridge Venting
Half Moon Bay’s marine layer keeps attics damp for months at a time, which is why a metal roof here needs different ventilation than an inland roof. We size ridge vents and intake ventilation for the fog cycle, not for summer heat. The goal is to move moisture out of the attic space before it condenses on the underside of the metal decking.
Tile Roof in Half Moon Bay
Tile Roof installation in Half Moon Bay carries a different set of challenges than tile does anywhere else in the Bay Area. Concrete and clay tile are heavy, durable, and handle the fog well, but the underlayment beneath them is what actually keeps your house dry. In Half Moon Bay, underlayment fails faster than tile does, because marine-layer saturation keeps it wet for hundreds of days a year. A full tile roof replacement in Half Moon Bay runs $26,000 to $48,000, with the higher end reflecting two layers of high-performance underlayment and stainless flashings.
Many of the 1970s ranch-style homes along the flats off Main Street and south toward Miramar were originally built with tile or compositioon roofs that predate modern underlayment materials. When we lift those tiles, the old felt paper underneath has often degraded to the point where it crumbles in our hands. That means the real work on a Half Moon Bay tile roof is not the tile itself; it is what sits underneath.
Fully Adhered Underlayment for Saturated Decks
We install self-adhering, high-temp underlayment across the entire deck plane on coastal tile jobs, not just at the eaves. Mechanically fastened felt paper leaves fastener holes, and in horizontally driven rain, those holes become entry points. The adhered system seals around every fastener, which changes how the roof performs in the winter storm season.
Stainless Flashings in the Valleys and Walls
Valleys collect both water and salt in this climate. We have pulled valley flashing from Half Moon Bay homes where the metal looked like lace after five years of south swell exposure. Galvanized does not belong on a coastal tile roof. Stainless steel is standard on our Half Moon Bay installs, and the estimate reflects it from the start.
Trusted Brands We Service in Half Moon Bay
Mercer Roofing installs manufacturer-recognized systems from GAF, CertainTeed, and Owens Corning, and we keep Half Moon Bay’s coastal realities in mind when we recommend one over another. For the fog-damp conditions on the flats, we lean on GAF Timberline architectural shingles with algae-resistant copper granules. For high-wind exposure near the bluffs, CertainTeed’s Landmark series with reinforced nailing zones holds against horizontal rain better than standard tabs. Whatever brand fits your home, we order locally and schedule delivery for the same week your tear-off begins, so you are not living under tarp for longer than necessary. Every brand we install carries a written manufacturer’s warranty, and every Mercer installation includes our 365-Day Done Right Promise on top of it.
Common Roof Installation Problems We See in Half Moon Bay Homes
- Marine-layer deck rot beneath shingles that look fine. The shingle surface can look worn but intact while the plywood or OSB decking underneath is spongy and failing. Half Moon Bay’s humidity keeps decks wet for months between storms, and rot spreads before anyone notices.
- Rusted-through galvanized flashing at valleys, walls, and penetrations. In the salt-laden air off Pillar Point, standard galvanized metals pit through in three to five years, opening leaks exactly where water volume is highest. Stainless or aluminum replacement is not optional on these homes.
- Wind-driven rain defeating shingle overlaps and step flashing. Winter Pacific storms push rain sideways, and standard shingle overlap tolerances were not designed for that angle. Water gets pushed under tabs and into soffit and fascia before the roof reaches half its expected lifespan.
- Moss and lichen packing the valleys on fog-side roofs. The persistent marine layer keeps north-facing and eave-side sections damp enough for moss to establish in the valleys, where it traps water against the shingles and accelerates granule loss and rot beneath.
Pricing for Roof Installation in Half Moon Bay, CA
You should know the numbers before you call. In Half Moon Bay, a standard architectural shingle tear-off and replacement on a single-story ranch runs $14,000 to $22,000. Two-story homes with steeper pitches run $18,000 to $28,000. Standing seam metal starts around $28,000 and runs to $42,000. Tile replacement starts at $26,000 and can reach $48,000 on larger properties near the bluffs. What moves the number: decking replacement, whether we find rotted sheathing once the old roof is off, how much stainless flashing your home needs, and whether the underlayment has to be stripped to the deck. We write those possibilities into your estimate as allowances, not as open-ended change orders. Call (743) 200-8347 for a free, written, line-item quote.
We Also Serve Cities Near Half Moon Bay
Mercer Roofing serves Roof Installation in Half Moon Bay and the surrounding coastal and bayside communities. If you are in El Granada, Burlingame, Millbrae, or Belmont, our crews are already familiar with the roofing conditions specific to each of those towns, from the hillside drainage challenges in Belmont to the marine-layer exposure in El Granada. Scheduling is coordinated through our San Francisco Bay Area office, and the same written pricing and photo-badged technician standard applies on every job.
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 About Roof Installation in Half Moon Bay
Because Half Moon Bay sits directly on the open Pacific, where the marine layer keeps relative humidity near saturation for a large portion of the year, while Redwood City, just 15 miles east over the Santa Cruz Mountains, dries out between storms. Moss and lichen spores need consistent moisture to colonize, and your roof rarely gets the dry break that an inland roof gets. On a 1968 split-level off the flats near Pillar Point, our crew tore off a composition roof that had been specified for inland conditions and found moss-packed valleys, rusted-through galvanized drip edge, and soft decking at the eaves. That is what this climate does. Call (743) 200-8347 to have us look at yours, estimates are free.
You really need stainless steel, or at minimum marine-grade aluminum. Standard galvanized flashing and drip edge on oceanside properties near Pillar Point and the coastal bluffs show visible rust and pitting within three to five years. That same galvanized metal would last 20-plus years just a ridge inland. The salt in the air chemically attacks the zinc coating, and once the coating fails, the base steel rusts through at the valley miters and wall intersections. On every Half Moon Bay install we specify stainless or aluminum flashing not as an upsell, but because no manufacturer’s warranty holds against standard galvanized in this air. Call (743) 200-8347 and we will show you the difference on your own roof.
Expect to find rotted decking at the eaves and in the valleys, rusted drip edge, and likely failed underlayment beneath shingles that have been shedding granules for years. Homes built in the 1970s on the Half Moon Bay flats were typically roofed with materials specified for inland conditions, not coastal salt and fog exposure. The marine layer has kept your deck damp for 50 years, and plywood rots from the underside. We write decking replacement into the estimate as an allowance, and if we find more rot than expected, you approve the additional cost in writing before we proceed. The price does not move without your signature. Call (743) 200-8347 for a free estimate on your ranch.
We install ice and water shield through the valleys and around every penetration, not just at the eaves, and we specify flashing profiles that turn water downward rather than relying on shingle overlap alone. Winter storms off the Pacific push rain nearly horizontally, and standard step-flashing tolerances fail under that force. On the oceanside homes we also use wider drip edge and sealed eaves to keep water from being driven up into the soffit and fascia. The goal is a roof that sheds water at every angle, because in Half Moon Bay, half your rain arrives sideways. Call (743) 200-8347 to walk through what that looks like on your house.
Possibly, and we handle it with a written inspection of your existing roof structure before we finalize the estimate. Half Moon Bay building code follows California energy and fire standards, and when a permit is pulled on an older home, the inspector may flag insufficient attic ventilation, undersized rafters, or missing edge metal that has to be brought up to current code. We write allowances for those items into your contract up front, and any change is priced and approved in writing before we touch it. That is the single biggest difference between a Mercer estimate and a quote from a company that has never worked a coastal tear-off. Call (743) 200-8347 to schedule your free estimate.
If your Half Moon Bay roof is showing moss, rust at the eaves, or leaks that only show up in winter storms, call Mercer Roofing at (743) 200-8347. You will get a written price, a real person on the phone, and a technician whose name and photo you receive before they arrive.
Written by Grant Whitlock, Owner at Mercer Roofing, serving Half Moon Bay and the San Mateo coast with roof installation you can verify at the door.