How a Mobile Home Roof-Over Works, Step by Step

A mobile home roof-over sounds simple — "a new roof over the old one" — but a roof-over that actually lasts is built in distinct layers, each doing a specific job. Here's exactly how we install a TPO roof-over, step by step, so you know what you're paying for.

Step 1: Pressure-Treated Perimeter & Nailers

We start by fastening a pressure-treated 2x4 perimeter and nailers across the roof with hurricane screws. This framework anchors the whole system and sets the depth for the insulation. We extend it across additions too — lanais, carports, Florida rooms, and patios — so the entire roof is tied together.

Why it matters: the nailers give the membrane something solid to terminate against, and their height is chosen so the insulation board sits perfectly flush.

Step 2: Rigid Insulation Board

Next we install rigid, foil-faced insulation board between the nailers so it sits flush with the framing. This is the layer that flattens the surface and adds real R-value to a roof that probably never had any.

Why it matters: this is where your energy savings come from. The insulation reflects and resists heat, so your air conditioner doesn't fight a hot roof all summer.

Step 3: The Heat-Welded TPO Membrane

Now the waterproofing. We roll out a single-ply TPO membrane across the roof and heat-weld the seams together into one continuous sheet. There are no taped or glued field seams to fail — the welds chemically fuse the membrane into a single watertight surface.

Why it matters: seams are where almost every mobile home roof leaks. A welded membrane removes that failure point entirely.

Step 4: Edge Metal, Fascia & Termination Bar

With the membrane down, we install new aluminum drip edge and fascia around the perimeter for a clean, finished look, and lock the membrane down with an aluminum termination bar fastened along the edge.

Why it matters: the perimeter is the second-most-common leak point. Proper edge metal and a termination bar seal the membrane to the structure so wind and water can't get under it.

Step 5: Vents, Boots & Penetrations

Finally, every penetration — vents, plumbing stacks, AC lines — gets new spun-aluminum hardware and a membrane boot that's heat-welded directly to the roof and sealed tight.

Why it matters: penetrations are the third classic leak source. Welding the boots to the membrane makes them part of the same seamless surface.

The Result

When it's done, you have a brand-new, insulated, fully welded roof — installed without tearing off your old one. No exposed interior during the job, no demolition costs, and 20+ years of leak-free protection plus lower energy bills.

Curious what it costs? See our Mobile Home Roof-Over Cost guide, or have our roof-over team take a look and give you a free estimate.