Low-Slope Roofs on Maine Homes

• Modified bitumen membrane. A continuous membrane sealed across the low-slope section, used where shingles would never hold up, like the back facet of our Brunswick project.
• Mechanical-lock standing seam. Field-seamed panels folded and crimped with a powered seamer, rated down to 1:12 (and sometimes lower with manufacturer-specific assemblies). Snap-lock panels need 3:12 or steeper. See standing seam metal roofing.

We don't install standing seam on truly flat roofs. Our low-slope work is the porch, ell, and addition roofs on homes.

Low-slope ells and porch roofs are vulnerable where snowmelt refreezes at the pitch change, and snow sliding off a steep main roof can load the porch roof below. Steep valleys that meet low-slope porches are common leak points. The transition between the two systems has to be detailed so melting snow can't back up underneath it, with ice & water shield where the water wants to go.

On a white Brunswick cape, we stripped the old shingles, opened up the 2-pitch section on the back of the house, and laid new plywood decking. The roof went back together with Grace ice-and-water shield at the eaves, synthetic underlayment across the field, architectural shingles on the steep slopes, and a modified bitumen membrane on the low-slope back facet.

See the full Brunswick project in our gallery.

If your low-slope section is leaking, we trace the leak to its real entry point before recommending anything; see roof leak repair. If the whole roof is due, we quote each section with the right system for its pitch as part of one written quote.