Exterior Painting for Sherborn, MA homeowners.

Two groups stand out in Sherborn's housing stock. Census estimates put about 20% of the town's homes at 1939 or earlier, and a Town of Sherborn preservation document notes that 77 old houses are listed on the National Register and that six or more houses in town have portions from the late 1600s. On the other side, 815 of the 1,588 housing units (51.3%) were built between 1950 and 1979, and the median year built is 1968.

Those groups need different exterior plans. An eighteenth-century clapboard house may carry many paint layers, some of them lead-based, over wood that has moved with every season since it was nailed up. A house from the 1960s usually has fewer layers and simpler trim, but it has also reached the age where caulk joints, window sills and the bottom courses of siding start to fail.

Inside the Sherborn Center historic district

The Sherborn Center Local Historic District was created by Town Meeting in 1983 and is bounded by North Main, South Main, Washington and Sawin Streets. Under the district's 2007 design review guidelines, exterior changes visible from a public way, a park or a body of water go to the Historic District Commission, and that includes replacing windows, doors, gutters or building materials.

Repainting is treated differently. The same guidelines exempt the color of paint on previously painted surfaces and state that no hearing is needed to repaint a house, though the Commission encourages colors that sit well with the neighboring buildings. Painting masonry that has never been painted is a different matter: the guidelines say it will not be approved. They also rule out swapping wood siding for vinyl or aluminum and recommend repairing original wood siding and trim. Because those guidelines date from 2007, confirm with the Commission before any work that goes beyond paint, such as replacing rotted clapboards with a new profile.

National Register districts and individual listings

The town also has two National Register districts: Sherborn Center and the Edward's Plain–Dowse's Corner district, which begins at Powderhouse Lane and extends north to North Main Street just north of Rockwood Street. According to the town's own preservation document, a National Register listing places no restrictions on the average private property; it mainly affects projects that use state or federal funds or permits. Outside the local district, then, choosing colors and repairing trim is up to you.

What prep looks like on older clapboard

Of the town's housing units, 72.9% were built in 1979 or earlier, so on a large share of houses here, older coats under the current paint may contain lead. Scraping and sanding those surfaces is done under lead-safe work practices: ground covers, containment, and cleanup that keeps chips out of gardens and play areas.

Once loose paint is removed, the job turns to the wood. Soft sills, split corner boards and decayed clapboard ends are cut out and replaced or consolidated with epoxy before any primer goes on. Bare wood gets an oil-based or bonding primer, open joints get flexible caulk, and the finish coats go on at a thickness the manufacturer specifies.

• Test suspect layers and set up containment before scraping
• Repair wood rot at sills, corner boards and window casings
• Prime bare wood the same day it is exposed when weather allows
• Finish with two coats of exterior acrylic matched to the surface

Big lots, long setbacks and damp ground

Because every property relies on its own well and septic system, the town requires minimum lots of one, two or three acres, and open space covers more than half of its land. The Massachusetts Historical Commission's 1980 survey also observed that many former colonial farmhouses, particularly in the southern and eastern parts of town, stand far back from the road. For an exterior crew, a setting like that can mean long carries from the driveway, uneven ground for ladders, and trees near the walls that shade some elevations.

The same survey describes a rugged upland with large areas of bog and swamp. Siding that faces wet ground or a stand of trees dries slowly after rain, so mildew is washed off and treated before painting, and a paint with mildew resistance makes sense on those elevations. Exterior painting in Massachusetts generally runs from late spring through early fall, when surface and air temperatures stay within the label range overnight. If rooms inside need attention as well, see interior painting in Sherborn.