Prefab fireplace repair specialists for Dover Shores East homes

Inside a factory-built chimney pipe

In one maker's system, each chimney section is a galvanized outer pipe around a stainless steel inner flue pipe, with a wire spacer holding the two apart. The sections snap-lock together as the chimney goes up, inner pipe first.

The space between the walls is part of the design. Dents that pinch that space, separated joints and rust on the outer pipe all go on our repair list with the section they affect.

• Galvanized outer pipe
• Stainless steel inner flue
• Wire spacer between the walls
• Snap-lock joints

Offsets and elbows in the chimney

Factory-built chimneys can jog sideways with elbows, within limits. Section R1005.7 keeps every piece of a factory-built chimney within 30 degrees of vertical and allows four elbows at most in the run.

One maker's manual adds its own rules for the length of angled pipe between supports and for the straps that carry the weight above an offset. When a chimney has been rerouted, we check it against both before any repair.

The storm collar on the chimney pipe

A storm collar is the band clamped around a metal chimney just above where it leaves the roof. It sheds water off the pipe and over the cone below, so rain runs onto the roof instead of down the outside of the chimney.

A collar that has slipped or lost its caulk lets water run straight down the pipe into the attic or chase. We reset or replace the collar and reseal it, then check below for water damage.

• Collar tight to the pipe
• Waterproof caulk around its perimeter
• Cone openings left open
• Attic checked below for water

Panels damaged by water

Refractory panels that have been soaked can soften, crumble or crack as they dry, and water stains running down them point to a leak above.

We stop the water first, then replace the damaged panels once the firebox is dry. Swapping panels before the leak is fixed only damages the new ones.

• Leak found and stopped first
• Firebox left to dry
• Soft or cracked panels replaced
• Retainers and steel checked behind them