Heavy Snow and Melt Leaks in Massachusetts

Speed matters with heavy snow and melt leaks in Massachusetts because the water keeps coming as long as the snow is there. After a big storm or a string of storms, the snow on a roof can sit for weeks and release water every time the sun or a mild day softens it. In the record 2014 to 2015 winter, Boston got more than 108 inches of snow, February 2015 alone brought about 64.8 inches, and MEMA logged 131 roof collapses statewide in the 13 days before February 22, 2015. Low-slope additions, porch roofs and valleys collect the deepest snow and tend to leak first.

In the first hour, meltwater soaks the attic insulation or the wall where a snowbank sits against the siding. By 24 hours drywall and plaster are wet, and water may be running down inside a wall into the basement. At 48 hours mold can begin on wet drywall, insulation and the bottom of the framing, especially in a warm basement. After a week of daily melting, roof boards and sill plates stay wet, finished basement walls wick water upward and the damage spreads well past the first stain.

Snowmelt is clean water at first, so framing, roof boards and sill plates can usually be dried in place with dehumidifiers and added heat, even in a cold attic, once the snow load is cleared. Drywall that is stained but firm can often be dried through small vent holes. In the basement, concrete walls and floors dry well with air movers once the standing water is out, and carpet can sometimes be dried in place if it only got wet at the edges along the wall. Wood subfloor and hardwood can be dried with mat systems.

What usually has to be removed is wet attic and wall insulation, drywall that sags or has wicked water more than a foot or so up from the floor, and soaked carpet pad. In a finished basement, water that ran in along the foundation and under the walls often means flood cuts along the bottom of the drywall. If melt water sat in a basement for several days, it is no longer treated as clean water, and porous materials it touched are usually replaced rather than dried.

Heavy snow leaks are most common where the snow piles up deepest. In Central Massachusetts, Worcester averages 72.9 inches of snow a year, the most of the major cities, and more than 40 percent of its homes were built before 1940. In Western Massachusetts, the hilltowns around Worthington average about 77 inches, and rural farmhouses and older homes there can carry snow for weeks. The North Shore and Merrimack Valley are close behind, with Newburyport at 61.9 inches and Haverhill at 57.8 inches a year, and even the Great Blue Hill station in Milton averages 69.3 inches.

Greater Boston had the record 2014 to 2015 winter, with more than 108 inches of snow, and South Shore towns like Hingham average about 51 inches in a normal year. On the Cape and the SouthCoast snow is lighter, with Hyannis near 21.5 inches a year, but one big storm can still bury porch roofs and window wells. In any covered town, one call connects you with a local restoration crew that can check the house top to bottom and start drying.