Fireplace Attic Chase

The manufacturors recommendation is 1 from the fp and 2 from the chimney to combustable materials.

Fireplace attic chase.

If the climate in your area is very cold insulate the chase to the top to keep the chimney warmer increase the draft and reduce creosote buildup. Climb into your attic and locate where your chimney system will enter this space. Any wood that is too close to the chimney will undergo a process called pyrolysis and even catch fire at temperatures as low as 200 degrees. You can also taper the chase above the fireplace.

The chimney chase top chimney chase cover is usually metal constructed of formed aluminum or stainless steel. Measure the height of the furthest point of the installation. Fire stops are self describing. A chimney installer indicated that i would need a firestop in this chase between the first second floor and another one 8 feet up from that.

Most of the units inspected by chimney professionals are improperly installed and a trip to the attic to check clearances is definitely time well spent. Doing this leaves room to encircle the chimney pipe. As currently designed the distance inside the chase to the chimney or firebox will be more like 24 on average with the closest spot about 6. They are installed to stop a fire in the chase area where the vent pipe runs through to get to the roof.

After you know where the penetration point will be for both attic and roof add 2 to all sides. We also recommend to insulate the ceiling of the chase just as if it were in the attic space. The interior of the chase has plenty of clearance to the fp and chimney. We find leaks here especially where the top is framed and enclosed flat and the top flashing lacks adequate pitch and stiffness to avoid collapsing even becoming concave where there are snow loads.

Seldom do we think about the fireplace metal vent pipe running up through the attic and roof. The rsf manual in the section about chases though they mean outer wall chases says. If this height exceeds 15 you are okay to install a attic insulation shield. My builder is saying that there is no requirement for a firestop since the chase and pipes are on the outside of the house with no floor or attic floor penetration.

Smaller dimensions for a rough frame of a chimney chase are about two square feet.