Tear-Off and Decking Come First
Roof replacement starts with a full tear-off, never an overlay. We strip old asphalt shingle, roofing felt, and tar paper down to the roof deck, then clear nails with a pry bar and a roofing shovel.
A decking inspection comes next. We probe plywood sheathing and OSB panels for rot, decay, and sag, because a soft substrate lets fasteners pull loose inside one season. Spongy sections get cut out and replaced.
- We drop a dumpster in the driveway, lay tarps to catch debris, and anchor a ladder and scaffold with a safety harness at the roofline.
- We remove the old field course and starter course, then check rafters, joists, and each truss for old water stains.
- We install self-adhered ice-and-water shield along the eave and through every valley, where ice dam risk concentrates.
- We roll synthetic underlayment across the field, then fasten new drip edge along the rake and the gutter line.
- We renew chimney flashing, step flashing at sidewalls, apron flashing and boot flashing at each penetration, plus every pipe boot and vent boot.
- We shoot architectural shingle with a coil nail gun and an air compressor in staggered courses, then cap the ridge and hand-seal details with mastic, roof cement, and roofing adhesive.
Materials We Install, and Why Each One Earns Its Place
Material choice sets service life, so we quote what actually fits the roof pitch, the framing, and how long you plan to stay.
- Architectural shingle like GAF Timberline or Owens Corning Duration carries a heavier mat than three-tab shingle and resists granule loss longer.
- Synthetic underlayment replaces felt and tar paper and survives foot traffic, keeping the substrate dry during install.
- Ice-and-water shield is a self-adhered membrane that seals around every nail and doubles as a vapor barrier at the eave.
- Standing-seam panel and corrugated panel sit on a batten or counterbatten layer, which lets metal move without backing out a screw.
- Flat sections take TPO, EPDM, or PVC membrane, and some older buildings still call for a built-up roof or a torch-applied modified bitumen cap.
- Ridge vent paired with soffit vent and attic insulation pushes hot air out, which lowers attic heat and summer cooling load.
What a Roof Inspection Covers, and What Failure Looks Like
Our roof inspection looks past the surface. We walk the rooftop, check the attic from the rafters up, and photograph anything that will not survive another winter.
- Granule loss at the shingle edge and bald south-facing slopes, an early mark of end-of-life wear.
- Curled, buckled, or missing shingle after a wind event, which lets rain seep under the course above.
- Corrosion on exposed fastener heads and a coating that has begun to flake or peel on metal panels.
- Cracked sealant or caulk at chimney flashing and counter-flashing, where most leaks start.
- Ponding water behind a parapet, a clogged scupper, and failed coping on a low-slope roof.
- Stained rafters, joists, a ridge beam, or a purlin, plus soft decking that points to a long-running leak.
- A sagging gutter pulling away from the fascia, and downspout hangers that have pulled free of the wall.
How Weather Around Here Changes the Work
Hot, dry summers and wildfire risk dry out the shingle mat and expose the eave and ridge to ember intrusion.
Frequent fog and morning dew keep the surface damp, which speeds decay on wood shake and cedar shake.
Heavy winter rain from Pacific storms tests every valley, dormer, and skylight, and that is when leaks surface at step flashing and skylight curbs.
Timelines, Cost Drivers, and Accessory Work
A typical asphalt shingle replacement runs one to three days from tear-off to final cleanup. Steep roof pitch, a second story, and rotted sheathing all add labor and time.
Cost drivers are square footage measured in roofing squares, material choice, and how much fascia and soffit repair the tear-off uncovers. Slate, clay tile, and concrete tile cost more in material.
We also refit the smaller pieces: verge and rake trim, an awning or porch canopy, an attic fan, and the snow guard brackets some foothill clients ask for.
Waterproofing at the eave and weatherproofing at every penetration is what keeps a roof dry, and each install meets California building code for fastening and ventilation.
We are a licensed and insured Santa Rosa roofing contractor, and you get a written scope before any tear-off begins. Call 415-687-5270 to schedule it.
