Chimney & Flashing Repair in Hackettstown, NJ

Why chimneys leak here

Hackettstown has a lot of older homes with brick and stone chimneys, and many houses in the area have fireplaces or wood stoves that get real use in winter. Every winter, water soaks into mortar, freezes, expands and pushes the joints a little further apart. Snow piles up behind chimneys and melts against them. Over enough years, the metal flashing that seals the chimney to the roof pulls away, rusts or gets buried under layers of tar from past "repairs".

Signs the chimney is leaking

• Stains on the ceiling or wall next to the chimney
• Damp or white-stained brick in the attic around the chimney
• Water in the firebox or around a wood stove
• Thick tar or caulk around the base of the chimney
• Crumbling mortar, loose bricks or a cracked crown on top
• Rust streaks or loose metal at the base

How chimney flashing should be done

A chimney that won't leak has layers:

• Step flashing - individual bent pieces woven in with each course of shingles along the sides, each overlapping the one below
• Counter-flashing - metal set into a groove cut into the mortar joints, folding down over the step flashing
• A cricket - a small peaked diverter on the uphill side of wider chimneys, so snow and water are steered around the chimney instead of collecting behind it. In snow country, this matters a lot.
• Ice and water shield under the shingles around the chimney when the roof is redone

Tar and caulk are a temporary patch. They shrink and crack in the cold, and they'll leak again.

Flashing vs masonry vs crown

Not every chimney leak is a flashing leak. Water can come in through:

• The crown - the concrete cap on top - if it's cracked
• A missing chimney cap, letting rain and snow straight down the flue
• Porous brick or failed mortar, soaking water through the chimney itself

A roofer can tell you whether the problem is the flashing, the masonry or both. Sometimes a mason is needed alongside the roofer.

Other flashing that fails

• Pipe boots around plumbing vents
• Skylight flashing - most skylight leaks are at the flashing, not the glass
• Wall flashing where a lower roof meets a two-story wall, common on additions and split-levels
• Valleys, especially on older homes with complicated roof lines
• Dormer flashing on capes and older homes

Wood stoves and chimneys

Many homes around Hackettstown burn wood in winter. A chimney that's used heavily goes through more heat cycles, and a leaking flashing detail lets water into the chimney structure, which can cause masonry damage over time. If you use a wood stove or fireplace regularly, have the chimney inspected and swept by a qualified chimney professional, and get the flashing checked when the roof is looked at.

Unused chimneys

Many older homes have a chimney that hasn't been used in years. It still needs sound flashing and a cap, because it can leak just like a working one. Sometimes the better long-term answer is having a mason cap it properly or take it down below the roofline.

When to fix it

Ideally before winter. A flashing leak that drips in fall rain can turn into a bigger problem once snow piles up behind the chimney and starts melting. If you've noticed a stain near the chimney, get it looked at before the snow season.