Ice Dam Water Damage in Manchester, NH

Ice dams are a Manchester winter fixture. Heat escaping through an under-insulated attic melts the snow on the upper roof; the meltwater runs down to the overhang, which sits outside the heated space, and freezes again. The ridge of ice grows, water pools behind it and works up under the shingles. From there it runs into the top of exterior walls, soaks attic insulation and comes through ceilings near the outside walls.

Why older Manchester homes get ice dams

• Capes, bungalows and old two-and-a-half story houses with little insulation in the knee walls and attic floor
• Recessed lights and bath fans that leak warm air into the attic
• Low-slope porch roofs on triple-deckers where snow sits for weeks
• Gutters packed with ice that hold water right at the roof edge

Drying ice dam water damage

Ice dam water is sneaky because it spreads inside the wall before it shows. The tech who does the walkthrough scans exterior walls and ceilings with thermal imaging, then checks the attic insulation by hand. Wet insulation usually has to come out because it stops insulating and holds water against the framing. Wall cavities under the eaves are opened or dried with injection systems, and plaster ceilings may need a section opened to dry the joist bays.

The drying team often has to work while the dam is still on the roof, so the leak can keep coming back with every warm afternoon. Getting the ice dealt with by a roofer or snow-removal pro matters as much as the drying.

Preventing the next one

Air sealing and insulating the attic floor keeps the roof deck cold, which is the long-term fix. The Department of Energy explains air sealing, and the Ready.gov winter page covers safe snow removal. Never chip ice off a roof with a hammer or climb an icy roof yourself. Water coming through a ceiling from a bathroom or the unit upstairs is covered on the ceiling leak page.