Why windows rot in Boston homes
Boston has some of the oldest housing in the country — brick row houses and brownstones in Back Bay and the South End, Victorians in Jamaica Plain and Dorchester, and thousands of triple-deckers. Many still have their original wood windows, and most sills and brick molding are decades past their last real repair.
Coastal nor'easters, wind-driven rain off the harbor, and repeated freeze–thaw cycles push water into every open paint crack. Once water reaches bare wood, rot starts at the sill and spreads into the sash and frame.
Signs your windows have rotten wood
- Wood feels soft or spongy when you press it with a thumb or screwdriver
- Peeling or bubbling paint on the sill or lower sash
- Dark, gray or green discoloration in the wood
- Cracks, splits or chunks crumbling off the sill
- Water stains or drafts on the wall below the window
- The sash sticks, rattles or no longer seals tight
What we repair
Window sill repair
The most common spot for rot — it catches rain and snow. We cut out the decay and splice in a matching profile.
Sash repair
Bottom rails rot where water sits on the glazing. We repair the rail or rebuild it and reglaze.
Frame & jamb repair
Soft side jambs are rebuilt so the window runs and seals properly again.
Brick molding & exterior trim repair
Rotted outside trim is replaced and sealed to the masonry or siding.
Patio & door frames repair
Rotted door jambs and thresholds repaired with the same splice method.
How we repair rotten wood windows
- 1
Free estimate
Send photos through the form or call. We confirm whether it's a repair job before anyone drives out.
- 2
On-site inspection
A technician probes every soft spot to find exactly how far the rot goes, then gives you a written price.
- 3
Remove the rot
Decayed wood is cut back to solid material — we don't hide rot under filler.
- 4
Splice in new wood
New lumber is shaped to match your existing profile and fastened in, so the repair looks original.
- 5
Seal, prime & paint
Joints are sealed, bare wood is primed and painted so water can't get back in.
More window repair in Boston, MA
Repair or replace your window?
Repair it when…
- Rot is limited to the sill, sash rail, trim or part of the frame
- You want to keep original wood windows and your home's character
- The rest of the window still opens and closes
- You want to save money versus full window replacement
Replace it when…
- Most of the frame and sash is soft all the way through
- The opening itself (framing behind the window) is structurally failing
- You already planned a full upgrade to new units
What affects the cost in Boston
- How far the rot has spread (sill only vs. sill, sash and frame)
- Number of windows repaired in the same visit
- Custom profiles that need matching on historic windows
- Window height and access (upper floors of triple-deckers)
- Paint and finish work needed after the repair