Spalling bricks on the weather-facing side
Why it happens here
Finderne's freeze-thaw cycle is brutal on older brick. Water soaks into the face, freezes overnight, expands, and pops the surface off. North and west faces take the worst of it. Once spalling starts it accelerates every winter, and the brick face is the chimney's first line of defense.
Our approach
We replace the spalled brick with matching units, repoint the surrounding joints with refractory mortar, and then waterproof the entire exterior with a breathable sealant. That combination stops the cycle instead of just covering the damage.