Two Roofs, One System — CertainTeed Landmark in Granite Gray Plus a Gaco Silicone Flat Roof, Portsmouth, RI

Like most Pinnacle roofing projects, the work was completed in a single day — minimizing disruption for the homeowner.

Pinnacle makes every roof affordable with monthly financing options to make your home project affordable with low monthly payments, including 0% interest for 18 months.

This Portsmouth property near the water had a leaking roof with two different problems: sloped sections that needed shingles and a flat section that shingles could never protect. Pinnacle Roofing & Skylights replaced it as one project with two right answers — the CertainTeed Integrity Roof System in Landmark Granite Gray on the slopes, and a Gaco silicone roof system on the flat.

Scope of Work

On the slopes: full tear-off, ice and water shield, synthetic underlayment, new drip edge and starters, Landmark field shingles in Granite Gray, rebuilt chimney flashing, and new ridge caps. On the flat: the deck prepared and cleaned, then the Gaco silicone system applied as a continuous fluid membrane — seams, penetrations, and wall terminations all sealed into one monolithic surface.

What We Installed (And Why)

CertainTeed Landmark handles the steep slopes the way dual-layer architectural shingles should — Class A fire rating, lifetime limited warranty, and Granite Gray’s blended granules reading crisp against white trim. But the story of this roof is the junction: where the shingle field meets the flat section, each system is terminated into the other so water has no seam to find.

Gaco silicone is a 100%-silicone fluid-applied membrane — it bonds to the substrate, bridges hairline movement, stands up to ponding water (the killer of flat-roof coatings), and reflects heat off the surface. For a coastal flat roof that takes salt air and standing winter water, it is the modern answer.

Project Photo Gallery

The brick chimney reflashed into the new Granite Gray field.

Where flat roof meets wall: the silicone membrane carried up and terminated watertight.

Good To Know: What’s the right roof for a house with both sloped and flat sections?

Two systems, one contractor. Shingles belong on the slopes; the flat section needs a true membrane — and the most failure-prone spot on the whole house is the transition where they meet. When one crew installs both under one contract, that junction gets engineered instead of improvised, and there is exactly one warranty conversation if anything ever weeps. Beware any quote that shingles the flat or ‘coats over’ the slopes.

Why This Approach Works

Matching each surface to its correct system — and detailing the junction once, correctly — is why this roof works as a whole. The silicone flat sheds ponding water it used to absorb; the Granite Gray slopes shed everything else.

Why Pinnacle

Pinnacle Roofing & Skylights is Firestone Building Envelope Certified for commercial roofing systems, and holds RI Commercial Roofing License #261. Pinnacle is a licensed Gaco applicator (and Mule-Hide, for other low-slope systems), alongside our Firestone commercial certification — flat, sloped, and everything between, under one roof license. With more than 100 five-star Google reviews and an A+ BBB rating, our track record speaks for itself.

Portsmouth, RI

Portsmouth’s waterfront homes and outbuildings mix rooflines the way island properties always have — steep gables over flat additions, all taking bay weather. Pinnacle serves Portsmouth with both shingle and membrane systems, matched to each surface.