Where the new roof meets the old one is the whole job
A covered porch is two structures at once. There is the deck or slab underneath, which is straightforward, and there is a roof that has to attach to a building that already has one. That second part is where covered porches succeed or fail, and it is the reason we treat this as roofing work rather than as carpentry with a roof on the end.
When a new roof plane meets an existing wall or roof, it creates a junction that concentrates water. Done properly, that junction is flashed — step flashing up the wall, a kickout at the bottom so water is thrown clear of the siding instead of running down behind it, and the existing roof covering lapped over the new flashing rather than sealed against it. Done improperly, it is a bead of caulk and a hope, and the failure appears as a stain on a bedroom ceiling about two winters later.
The other decision worth making deliberately is gabled or shed. A shed roof is simpler and cheaper, and it works well where the porch is not deep and the existing eave is high enough. A gable costs more but gives headroom, lets light through, and on most houses around here looks like it belongs. We will tell you which one suits your elevation, and we will tell you if the answer is the cheaper one.
- Flashed as roofing. Step flashing and a kickout where the new roof meets the wall, lapped correctly into the existing covering.
- Gabled or shed. Chosen against the house's own roofline and eave height rather than by what is quickest to frame.
- Structure sized for the roof. Footings, posts and beams carrying a real roof load, not deck framing with a cover on top.
- Ceiling finished. Boarded underside, with blocking for a fan and boxes for lights installed before it closes.
- Railing to suit. Hog-wire, cable, timber or aluminum, matched to whatever the rest of the outdoor space uses.
- Matched to the house. Roof covering, trim, column detail and fascia picked so the porch reads as original.
How we build a covered porch
Read the existing roofline first
Eave height, existing pitch and where the ridge runs decide what is actually possible. A porch roof that has to squeeze under a low eave ends up with a pitch too shallow to shed properly, and that is a leak waiting to happen. We work this out before anything is designed.
Footings and posts for a roof load
A covered porch carries considerably more than an open deck. Footings and posts get sized for the roof, not for foot traffic. Where an existing deck is being covered, we get underneath and check whether it can take it before agreeing to.
Frame and tie in
The porch roof is framed and connected to the house, then flashed — step flashing up any wall, kickout at the bottom edge, and the existing roof covering lapped over the new work rather than sealed to it.
Roof covering and trim
Metal panel or shingle to match the house, then fascia, soffit and gable trim. This is the part that decides whether it reads as original or as an addition.
Ceiling, lighting and finish
Ceiling boarded, with fan blocking and light boxes already in. Then columns, railing and a walk round with you.
Why homeowners choose us for this
We are roofers
The junction between a new porch roof and an existing roof is a roofing detail. We flash it as one, which is why ours are not the ones staining a ceiling in two winters.
We check the deck can take it
If you already have a deck, we get underneath and look at the footings and posts before agreeing to put a roof on it.
Gable or shed, chosen honestly
Sometimes the cheaper shed roof is genuinely the right answer for the elevation, and we will say so.
Wiring before the ceiling closes
A fan and lights cost almost nothing to provide for now, and are ugly and expensive to add later.
Covered Porch Questions
Sometimes, and the answer is underneath rather than on top. A roof adds significant load, so the footings, posts and framing all have to be capable of carrying it. We will get under the deck and look before saying yes. If it cannot take a roof, we will tell you what it would take to make it capable rather than building on it and hoping.
It can, and it is worth thinking about before rather than after. A deep porch across a wall of windows cuts a lot of daylight from the rooms behind it. Options that help are a gable rather than a shed roof, a shallower depth, or building a freestanding pavilion somewhere else in the yard instead. We will raise this rather than let you discover it in November.
Shed is simpler and cheaper and works well where the porch is shallow and the existing eave is high enough to give the roof a decent pitch. Gabled costs more, gives headroom and light, and generally suits the houses around here. The constraint is usually the eave height of the existing roof, which we will measure.
With flashing, not sealant. Step flashing runs up any wall the roof meets, a kickout at the bottom throws water clear of the siding instead of behind it, and the existing roof covering laps over the new flashing. Caulk at that junction is a temporary measure that fails on a predictable schedule, so we do not build on it.
Yes, and it is worth deciding at the design stage. Screening changes the post spacing and the framing around the openings, so a porch built with screening in mind is straightforward to screen and one built without it is a retrofit. Tell us it is a possibility even if you are not doing it now.
Generally yes, since it attaches to the house and adds a roof structure. It varies between Whitfield County, the City of Dalton and the Tennessee jurisdictions we work in. We will tell you what we understand applies to your project when we come out and quote it.