Chimney and Chase Repair for Hideout Homes

The chase is a building, not a chimney

What looks like a chimney on most Hideout houses is a framed timber box, clad in siding or stone veneer, with an insulated metal flue inside it. Understanding that changes how you think about failure. A masonry chimney is solid and takes water damage slowly, over decades. A framed chase is a wall assembly, and water that gets inside one behaves like water inside any wall: it wets the sheathing, rots the framing, and does it silently because the whole cavity is sealed and nobody is ever in there.

Chase tops are the usual culprit

The lid on top of that box is a metal pan. Done well, it is heavy-gauge stainless or aluminum, sloped to shed, with a cross break so it cannot pond, an overhanging drip edge, and a properly sealed collar where the pipe comes through. Done cheaply, it is thin galvanized, dead flat, with a caulked pipe penetration. The flat one holds a puddle every time snow melts on it. Standing water rusts galvanized from the top down, and the caulk around the pipe has a service life measured in a few years, not the life of the house. Then the water is inside the chase.

Signs from the ground are staining down the chase sides, rust streaks below the top, a sagging or oil-canned pan, and interior clues like a damp smell near the fireplace or paint lifting on the adjacent wall.

Flashing, on a steep roof, under snow

The other entry point is where the chase meets the roof. On the pitches common here, snow does not sit and slowly melt so much as it builds and then moves, and moving snow works at any detail that stands proud of the plane. A flashing that relies on sealant instead of a proper step and counterflashing arrangement will eventually be opened by that. We would rather rebuild the detail than add more sealant to it, because sealant is what failed the first time.

What repair looks like

New chase cover fabricated to fit, in stainless where the exposure justifies it, sloped and cross-broken, with an overhang and a mechanically sealed collar. Flashing rebuilt as flashing. Rotted sheathing cut out and replaced where we find it. Stone veneer repointed or reset where it has come loose from the substrate, and the veneer's own drainage checked, because a veneer with no way to drain behind it holds water against the frame.