RoofingCliftonCincinnati

Clifton Cincinnati GAF HDZ Williamsburg Slate Roof 2024

A Tudor in Clifton with steep gables, a dormer and a copper-capped chimney — a house that looks like it has one roof and actually has two. Most of it is steeply pitched shingle work. Behind a parapet wall there is a flat section. The house had been leaking, and the attic ran hot.

Everything came off down to the deck. The steep planes took GAF Timberline HDZ in Williamsburg Slate, laid in an offset pattern for moisture protection and fastened with five nails per shingle to meet the manufacturer's requirement, over 36-inch ice-and-water shield with GAF starter shingles around the home. The flat section took a 60-mil rubber membrane adhered to the deck and counter-flashed into the parapet walls, so water coming down the masonry is thrown out onto the membrane rather than behind it.

Ventilation was sized to the recommended one square foot for every three hundred square feet of area, with a Snow Country ridge vent and Seal-A-Ridge caps at the peaks and edge ventilation added to feed it.

One decision on this house is worth naming on its own. The perimeter carries roughly 165 feet of edge metal — but not the whole way around. Where that metal would have run across the ornate wood trim that wraps the house, it was left off deliberately, and the shingles were held to a half-inch overhang past the wood fascia instead. Gutter apron protects the gutter line where it belongs. The woodwork that gives the house its face stays visible, and the roof still terminates the way it should. That is the kind of thing that has to be decided before the truck is loaded, not discovered halfway through a tear-off.

Landscaping and the ground around the house were tarped through the tear-off, and the perimeter got two passes with a magnet at the end. What the house has now is one roof again, which on a building like this one is more of an achievement than it sounds.

Dormer and copper-capped chimney on the Clifton Tudor roof

Steep stucco gables and new shingles on the Clifton Tudor from the side yard

Technical Discussion

One house, two roofs

Older houses in neighbourhoods like Clifton almost always have a flat section somewhere. A porch roof, a back addition, a section tucked behind a parapet so it cannot be seen from the street. Because it is invisible, it tends to be treated as a small part of the roof. It is not a small part of the roof. It is a different roof, obeying different rules, that happens to be attached to the first one.

A shingle roof does not waterproof anything. It sheds. Every shingle hands water to the one below it, gravity does the work, and the steeper the pitch the more forgiving the whole arrangement becomes — which is why a steep Tudor plane can take a hard rain and a bad afternoon and still be fine. A flat roof gets none of that help. Water does not run off it; it sits on it, sometimes for days. So a flat roof has to be watertight rather than merely water-shedding, which means a continuous membrane with no upward-facing seams for water to work into. Two different materials because two different physics. There is no single product that is good at both, and a roof that pretends otherwise is a roof with a date on it.

Which means every house like this one has a junction, and the junction is where these roofs fail. Almost never in the middle of a field of shingles, almost never in the middle of a membrane. It fails where the flat roof meets the sloped roof, and where the flat roof meets the wall it dies into.

On this house the flat section sits behind a parapet — a low wall that continues up past the roof surface. A proper transition there is not the membrane stopping at the base of the wall. The membrane turns up the inside face of the parapet and becomes, for that height, the wall's covering. Then the top edge of that turn-up is counter-flashed: a second piece of metal is let into the masonry above and laps down over the membrane's top edge, so any water running down the wall is thrown out onto the membrane and cannot get behind it. Skip that and you have a cut edge of membrane facing straight up at the sky, waiting. Sealant will hide it for a couple of years, which is long enough for everyone to forget it was ever a shortcut.

If your own house has a flat section, this is the question to ask whoever quotes it: what happens exactly where the flat roof meets the wall, and exactly where it meets the sloped roof? If the answer is caulk, you are buying a repair with an expiry date rather than a roof. And if a ceiling below one of those areas stains, look at the transition first — the field above it is usually fine.

Our Work