Chimney chase repair with a written estimate in Merrimac

Telling a framed chase from a masonry chimney

Plenty of homeowners are not sure which kind of chimney they have, and it changes the whole repair. A masonry chimney is solid brick or block with a flue inside. A framed chase is a wood box around a metal pipe.

If the chimney turns out to be masonry, the job belongs to a different repair, and we tell you so on the spot. Stucco over block is patched as masonry work. Stucco over a framed chase in Merrimac is part of chase repair, because the wood behind it is what fails. These clues sort it out from the ground.

• Siding or stucco that matches the house walls, with no brick joints
• A flat sheet-metal top instead of a poured concrete crown
• A round metal chimney cap rising from the top instead of a clay flue tile
• A metal firebox with a maker's label inside the fireplace opening

A chase that hangs off the wall on a framed floor

A cantilevered chase never reaches the ground. It sticks out from the house wall at fireplace height or higher, sitting on a small framed floor with a soffit panel underneath. From below it looks like a narrow bay built around the chimney.

That floor and soffit belong to the chase. Water running down inside the box collects on the floor framing, and a sagging soffit or a stained underside panel is often the first sign. Rot there can spread to the joists that tie the small floor back to the house wall, so the floor gets probed along with the walls.

When we open a cantilevered chase, the floor joists, the soffit and the connection to the house wall get checked together. Your estimate lists the soffit and any floor framing as their own items. The soffit panels usually come down first, since they show the floor framing from below without opening the walls.

Rotted roof deck around the chase base

Water that rots the bottom of a roof chase often reaches the roof deck under it. The plywood around the chase opening goes soft, the shingles above it sag, and the rafters or blocking under the chase may be wet too.

The chase sits on that roof framing, so a soft deck is a structural question as well as a roofing one. It also affects how the new chase framing is fastened down, since the base plate needs firm wood under it. Replacing chase siding over a rotted deck leaves both the leak and the weak base in place.

Once the base of a chase in Merrimac is open, the deck and blocking are checked by hand, and new framing never goes down on soft deck. Deck repair is listed separately, and if your roofer is handling the shingles, we agree on who replaces which pieces before work starts.

Sealant at siding joints versus near the pipe

Sealant has a job on a chase, but a narrow one. At siding joints, trim and the seam with the house, an exterior-grade sealant closes gaps where the siding maker calls for a seal. It is maintenance, not a stand-in for flashing or a barrier. Old sealant is cut out before new goes in.

Near the chimney pipe it is a different matter. Chimney makers can name specific sealants for specific joints at the chase top. DuraVent's instructions, for example, call for a non-hardening waterproof sealant at certain chase-top joints and keep the ventilation openings clear.

Our crew uses the product each maker calls for in each place and never fills the air space with caulk or foam. If old caulk is bridging the gap to the pipe, we remove it and tell you why.