The Stove Pipe Through Your Roof Needs Its Own Quote Line

If your house has a wood stove, a stove insert, or a fireplace that vents through the roof, that pipe is part of the roof job whether the quote says so or not. Most St. Charles roof bids list shingles, underlayment, drip edge and a general line for flashing. The stove pipe penetration often gets folded into that general line, which means nobody has agreed on who pulls the old flashing, who caps the opening at the end of the day, who reflashes the new roof around the pipe, or who checks the clearance when the crew leaves. This page is for the homeowner who is still deciding and wants one specific thing in writing before the first bundle lands.

Why a stove pipe is not a plumbing vent

A plumbing vent is a thin pipe that carries sewer gas out of the house, and most roofers treat its boot as a routine part of the job. A stove pipe or chimney connector carries hot flue gas, and the place where it passes through the roof is built around a listed assembly. In most installs that means insulated or double-wall pipe running through a roof thimble or a support box, a flashing sized to that thimble, and a storm collar that seals the flashing to the pipe. Single-wall stove pipe usually needs a clearance to combustibles set by the stove maker, which is a specific air space between the hot pipe and the roof deck, rafters and any ceiling material around it. The manual for your appliance sets those numbers. Ask the roofer to read the clearance line from that manual before the decking around the pipe gets cut, because a rafter that was fine with the old shingles can become a problem once the new layers go on.

The height rule a roof change can break

The rule that most chimney standards use is that the top of the pipe must sit at least three feet above the point where it passes through the roof, and at least two feet above any part of the roof within ten feet horizontally. A new roof adds shingle thickness, and on a low-pitch section the change can shift which part of the roof falls inside that ten-foot circle. A new ridge, a dormer or a second roof plane close to the pipe can change the answer too. The exact requirement depends on the appliance listing and on your local rules, so check the manual and ask the permit desk, but do not assume the old height still works after the work is done. A roofer who replaces the shingles around a pipe without measuring the new height has changed the chimney, even if nobody meant to.

What the quote should name

A general line that says flashing and penetrations is not enough for this detail. Ask the proposal to name each piece. The lines that matter are these:

• The thimble or support box, with the model, and whether it is new or reused from the old roof.
• The flashing kit, and whether it is sized to the pipe diameter in use, not just to the roof opening.
• The storm collar, and the sealant or fastener used where it meets the flashing.
• The cap or rain shield at the top of the pipe, and who supplies it.
• Whether the pipe comes off and goes back on, or is replaced with new sections.
• Who reconnects the stove pipe inside the house, and who checks the clearance before the stove is lit again.

Keys Roofing installs Atlas and Malarkey shingles, and the shingle lines on the proposal are a separate question from the penetration lines. Keep them apart on the page so the flashing work does not get absorbed into a shingle price that looks complete on its own.

Who cools the stove before the crew arrives

The stove or insert needs to be cold, and the pipe disconnected at the appliance end, before any roofer works within reach of the pipe. Ask the roofer to say that in writing, along with the date the stove will be shut down and who tells you when it is safe to light it again. The reverse matters too. A pipe capped with a loose piece of tin or a cloth is a problem in the first rain, and during tear-off the roof may be open overnight. Ask who covers the opening at the end of each day and what that covering is. If you plan to keep the house heated during the job with a different source, that is a question for your heating provider and your stove installer, and it is worth settling before the crew is on the roof rather than on the morning the pipe comes out.

The St. Louis winter shows a loose collar first

Freeze and thaw is the reason this detail has to be right the first time. Water runs down the pipe during a thaw, gets under a storm collar that was not sealed well, and refreezes in the gap. By February the gap is wider, the sealant has cracked in the cold, and the stain shows on the ceiling near the stove wall or in the attic beside the pipe. Ice damming at the eave can make it worse, because meltwater backs up under the shingles and finds the nearest penetration. Hail season in the spring can dent a cap or crack a collar, and a dented cap is easy to miss from the ground. Schedule the penetration work before the first hard freeze if you can, and ask the roofer to check the collar again after the first thaw, since that is when a bad seal first shows.

Photograph the pipe before and after

Before the tear-off, take photographs of the stove pipe from the roof side and from the attic side, including the thimble, the old flashing, the storm collar and the top of the pipe with a tape measure in frame. These photographs are your baseline. After the work, take the same shots again, plus a close-up of the storm collar and a photograph of the label on the thimble or support box. Keep both sets in a dated folder with the proposal and the written scope. Keys Roofing documents the job with photos and measurements and puts a written scope in your hands, and this is one of the places where that paper trail matters most. Your own folder is the record you keep, whatever the roofer provides.

Ask the permit desk about the stove, not just the roof

A roof permit does not automatically cover work on a stove or an insert. Rules for appliance and chimney work vary by jurisdiction, and some municipal permit desks treat the stove as a separate item from the roof. Before the job starts, call the permit desk for your address and ask two things: whether the stove or pipe work needs a permit or inspection of its own, and whether the roof permit covers the penetration. Do not assume the answer from a neighbor's job, because two houses on the same street can fall under different rules if they sit in different jurisdictions. Get the answer in writing if the desk will give it that way, and put the permit number on the proposal next to the penetration lines.

Questions to ask before you sign

1. Which line on the proposal covers the thimble, the flashing and the storm collar, and what is the model of each?
2. What height will the pipe top be above the new roof, and what does the appliance manual require for that height?
3. Who disconnects the stove and caps the pipe opening, and who covers the opening each night?
4. Who reconnects the pipe, who checks the clearance, and in what order does that happen before the stove is lit?

If you would like the stove pipe looked at on your own roof before you compare bids, call Keys Roofing at (314) 220-2333 and ask for the penetration lines to be written out by name, so you can compare them with the other proposals on the same sheet.