Roofing Services in Union City
Decoto and Alvarado were separate towns long before Union City existed, and their roofs still show it. Most 1950s ranch tracts here are on their third or fourth layer, so a roofer needs to know what sits under the shingles.
What We Find on Union City Roofs
- Asphalt shingle layers — much of Decoto carries three-tab or architectural shingle laid over roofing felt and tar paper that has dried out in the sun.
- Wood shake and cedar shake — a few pre-war Alvarado buildings still wear them, and they split and rot where shade keeps the decking damp.
- Clay tile and concrete tile — heavier roofing on the Mediterranean-style houses up the hills, where a purlin, batten, and counterbatten check comes before anything is reset.
- Standing-seam panel and corrugated panel — metal panel roofing we fit on patio covers, awnings, and carport canopies that sit below shingle pitch.
Plenty of low-slope sections over garages and rear patios can't take another overlay. When pitch flattens, we tear off to the decking and switch to a membrane system instead of forcing shingles onto a surface that will pond.
Low-Slope Systems We Install
- TPO and PVC membrane — single-ply sheets heat-welded at the laps, which handle ponding water better than any shingle can.
- EPDM — a rubber membrane we still use on flat rooftop sections where a homeowner wants a lower-cost refit.
- Modified bitumen and built-up roof — torch-applied or mopped systems for low-slope decking over garages and additions.
- Roof coating — a reflective coating over sound modified bitumen buys years on a flat roof that is not ready for replacement.
How We Roof a House in Union City
- Tear-off first — we strip to the sheathing with a roofing shovel and pry bar, then check plywood and OSB decking for rot and delamination.
- New substrate and underlayment — synthetic underlayment across the field with ice-and-water shield at the eaves and valleys, where ice dams and backed-up water do the most damage.
- Flashing done properly — step flashing at sidewalls, counter-flashing and chimney flashing at masonry, and a new pipe boot at every penetration.
- Complex rooflines — hips, gables, and dormers create valleys where water concentrates, so those planes get extra underlayment and hand-sealed step flashing.
- Ventilation balanced — ridge vent at the peak and soffit vent under the eave keep attic insulation dry and stop heat from cooking the shingles.
- Gutters and downspouts — we re-pitch and reseal them, because clogged gutters under the hillside oaks cause most of the fascia and soffit rot we see.
- Tools and staging — scaffold and ladder access, a safety harness tied to a roof anchor, a dumpster for debris, and material ordered by the roofing square.
- Sealants and fasteners — we hand-seal what needs it with roof cement or mastic, and set every fastener and screw to the right depth so nothing is overdriven.
- Framing checks — if a truss, rafter, joist, or ridge beam has sagged, we sister or replace it before the new roof goes down.
- Parapets and flat edges — on townhomes near Union Landing Boulevard we reseal coping and check the scupper so water leaves the parapet wall.
Any reroof that covers more than half the roof area triggers cool-roof rules under Title 24, which the Union City Building Division enforces. That pushes most local jobs toward reflective shingles or cool-rated membrane products, and we price it in from the start.
We are a licensed and insured crew based in San Ramon, and we know these streets: Decoto Road past the BART station, the tracts off Alvarado Boulevard, and the hillside blocks backing onto Dry Creek/Pioneer Regional Park.
Call 925-723-9025 for a free roof estimate.
Common Roof Problems in Union City
Most calls we get from Decoto and the Alvarado flats start the same way: a brown stain on a ceiling after the first heavy winter rain. By then water has often been wicking along the underlayment for a season.
On the third and fourth shingle layers common here, leaks rarely start in the field. They start at the flashing — a chimney flashing that has pulled loose, a pipe boot cracked by sun, or step flashing never hand-sealed at a sidewall.
Shade is the other problem. Coast live oak and eucalyptus over the eastern hillside streets drop leaf litter into valleys and gutters, so debris dams the runoff and it seeps sideways under the shingles. That shows up later as rot in the fascia and soffit, and sometimes a sagging roofline where a rafter has taken on moisture.
We also see granule loss and end-of-life wear on south-facing planes, plus blistering and peeling on any flat rooftop section that ponded all winter. A spring roof inspection usually catches it before it reaches the roof deck.
If you have a drip, a stain, or a shingle curled at the ridge cap, call 925-723-9025. We give a free estimate and tell you plainly whether you need a roof repair or a full replacement.