Rainscreen Clapboard Siding for an Energy-Efficient Island Remodel
Making an old house energy-efficient is a technical challenge, particularly in the severe climate of coastal Maine. JLC has been visiting one job site to follow the work on just such a project: the structural upgrade and energy-efficient gut/rehab of an old summer home on Peaks Island, an island neighborhood a short ferry ride from the Old Port section of Portland, Maine.
Like many homes on the island, the project house was lightly framed and had never been insulated before island contractor Thompson Johnson Woodworking started its ground-up makeover. Structural rehab was the first challenge: last fall, project supervisor Mark Pollard and his crew spent weeks jacking, straightening, and re-framing the structure, creating a new, flat second floor and cranking the racked and sagging roof system into some semblance of straight, plumb, level, and square.
As winter took hold, Pollard said wryly: "We're almost done with the inside work. Now it's time to work on the exterior." From January through spring, through a series of record-setting New England snowstorms, the crew wrapped the outside of the board-sheathed house with an airtight layer of Grace Ice and Water Shield, and then applied two layers of foil-faced foam insulation sealed with tape. As warmer weather crept in, the crew started to side the house. The lower story walls are sided with clapboards, requiring the crew to first apply strapping and vent screens to create a drainable, ventilated rain screen system. On the upper-story dormers, the crew used pre-primed wood shingles applied over an air gap created with MortairVent from Advanced Building Products.
For details of the clapboard rain-screen system, see the slideshow. Check back later for a step-by-step slideshow of the shingle application on the upper story.