Patio Covers / Metal Roof
Metal Roof Patio Covers in Cowlitz and Clark County
Metal goes on most of the covers I build, and the reason is slope. An attached cover has to duck out from under the existing roof, which usually leaves it far flatter than the house, and metal sheds water at a pitch where shingles will not.
How I build it
Posts: Pressure-treated 6x6 on standoff post bases.
Footings: Poured concrete piers, or anchored to an existing slab where the slab is thick enough.
Beam: Glulam or built-up beam, sized to the span.
Rafters: 2x8 or 2x10 at 24 inches on center, sized to span and snow load.
Sheathing: 1/2 inch CDX over the rafters.
Air gap: Counter-batten over the sheathing, under the panel.
Roofing: Metal panel.
Wall connection: Ledger flashed under the siding and counterflashed, never caulked on top.
Composition shingles have a minimum pitch they are allowed to run at, and an attached cover often cannot get there. The roof has to start below the existing eave and still have headroom at the outside edge, and on a single-story house that leaves very little fall. Metal panel runs flat enough to work in that space. That constraint is usually what picks the roof, not what anybody likes the look of.
The way I build the assembly is panel over 1/2 inch CDX with a counter-batten between them. Most metal covers are panel screwed straight to open purlins, which is faster and cheaper, and it leaves you looking up at the underside of the panel and the screw tips for the life of the cover. The solid deck gives a finished ceiling. The batten leaves an air gap so the condensation that forms on the underside of metal can dry and drain instead of sitting against the sheathing.
Two honest downsides. It is loud in hard rain, which some people love and some people cannot stand, and you should decide that before it is built, not after. And a dark panel picks up heat, so on a west-facing patio in August the cover will be warm overhead.
Where a cover leaks is almost never the field of the roof. It is the wall. The ledger has to go on with flashing that runs up behind the siding and over the top of the ledger, so water coming down the wall lands on top of the flashing and gets carried out. Caulk across the top of a ledger is a two-year fix that looks like a repair for the next ten.
Included
Pressure-treated 6x6 posts and standoff bases
Concrete footings or slab anchorage
Beam, rafters and 1/2 inch CDX sheathing
Counter-batten and metal roof panel
Flashed and counterflashed ledger at the wall
Permit drawings and permit application
Hardware and fasteners
Not included
Concrete patio slab, if there is not one already
Electrical, including fans and lighting
Gutters and downspouts, quoted separately
Painting or staining
Removal of an existing cover, quoted separately
Want this cover on your patio?
Call for a free estimate, or send photos and get a Project Sketch first. Call (360) 431-9382.