No. In a site-built home, stove pipe never runs out through a window or its glass. Run the chimney through the exterior wall beside the window, with listed Class A chimney pipe inside a wall thimble, or straight up through the roof, installed to your kit's instructions, as IRC section R1005.1 requires where adopted.
This page answers "Can you vent a wood stove through a window?" for houses built on site.
A skoolie, a campervan, a tiny home on wheels or a mobile home is a different install, and this page does not cover them. Our guides to installing a stove in a campervan and to a wood stove in a mobile home cover two of them.
Can You Run a Wood Stove Pipe Through a Window?
No, not in a house. Where your area has adopted the 2021 International Residential Code (IRC), the code clause on this is section M1803.3.1, in chapter 18.
There is no national US building code: codes are adopted locally, so your building department confirms which rules apply.
In our words, it says a chimney connector shall not pass through any floor or ceiling.
For a wood stove, it may pass through a wall in two cases only. Either the connector is listed and labeled for wall pass-through, or it runs through a device that is. Either way it is installed to the conditions of that listing and label.
A window, its glass and its frame are none of those things. The stove pipe is the connector, and section M1803.3 keeps connectors within the space where the appliance is located.
Our kits follow the stricter line. The through-the-wall kit page says: "Stovepipe must never pass through the wall. Only insulated Class A chimney pipe may enter the wall thimble."
Can You Replace the Glass With a Metal Plate?
Not as a house install: our kits never run stove pipe out through a window, and a plate would meet the code only if it were itself listed and labeled for wall pass-through.
Searches for a wood stove window vent kit also turn up window plate kits sold for tent stoves. Check any such kit's label. Without a listing and label for wall pass-through it is not the install M1803.3.1 describes for a house.
The listed routes in a house are a wall thimble with Class A pipe through it, in the wall next to the window, or a Class A chimney straight up through the roof. The window stays a window.
What to Do Instead of Venting Through a Window
Leave the window as it is and take one of two routes: through the wall beside it, or through the roof. Both use insulated Class A chimney pipe from the point where the chimney leaves the room.
Through the Wall Next to the Window
This is a through-the-wall install, done as the Class A installation instructions set out on pages 19 and 20.
- Ask your building department what it needs. Page 3 of the instructions says to contact your local Building Official or Fire Official about restrictions and installation inspection.
- Choose where the chimney passes, in solid wall beside the window, not through the window or its frame. Page 19 says it should pass through the wall centered between two studs.
- Cut and frame an opening in the inner and outer walls, sized from Table 1 of the instructions.
- Fit the outer half of the wall thimble from outside and the inner half from inside, with the shields sliding together.
- Fit a Class A section to the tee, slide it through the thimble from outside, and fit the base wall support below the tee.
- Build the chimney up the outside wall with wall brackets, to the height of the 3-2-10 rule, and fit the chimney cap on top.
Straight Up Through the Roof
Where the room has the roof or an attic above it, the chimney can run straight up instead. Our through the roof chimney kit takes Class A pipe up through the ceiling and the roof, with the support, firestop and flashing for that route.
Treat the wall as combustible if it contains wood framing, as our kit page asks; it adds that most US exterior walls do. A brick or stone face over wood framing does not make the wall non-combustible.
Our kits for a wood stove pipe through wall route keep the stove pipe inside the room and send Class A pipe through the thimble.
What the Wall Kit Holds
A 6 inch build on our through-the-wall kit page includes:
- The wall thimble, for the pass through the wall.
- A tee with clean-out cap, outside the wall.
- A 9 inch Class A insulated chimney pipe section, with the outside lengths set by the height you choose in the kit's questions.
- A base wall support kit and an adjustable wall bracket.
- Telescoping single wall stove pipe and an adapter from stove to stove pipe, for inside the room.
- A stove pipe adapter to Class A pipe, where the stove pipe meets the chimney inside the room.
- A chimney cap with spark screen, for the top.
Inside, the stove pipe ends before the wall. The kit page says it "must stop before the wall and remain at least 18 inches from combustible materials."
What Clearance Does the Pipe Need Near a Window?
Class A chimney pipe needs at least 2 inches to combustibles, per the installation instructions of the system installed.
Page 3 of our instructions also says never to fill a required clearance space with insulation or any other material.
Single wall stove pipe needs 18 inches. That figure is in IRC Table M1803.3.4 for single wall metal pipe connectors serving oil and solid fuel appliances, and page 3 of our instructions repeats it.
| Part | Clearance to combustibles | Where the figure comes from |
|---|---|---|
| The stove | As its label and manual give it | The stove's listing and manual |
| Single wall stove pipe | 18 inches | IRC Table M1803.3.4 and page 3 of our Class A instructions |
| Class A chimney pipe | At least 2 inches | The installation instructions of the system installed |
Count what sits around the window next to the chimney. Page 3 lists lumber, furniture and curtains among combustible materials, so measure from the curtains and any wood trim as well as from the wall.
The 18 inches can come down in two cases, page 3 adds. One is a clearance reduction system acceptable to the authority having jurisdiction. The other is a listed appliance whose instructions specify a different clearance.
How Close Can a Chimney Outlet Be to a Window?
Neither chapter 10 nor chapter 18 of the 2021 IRC, nor our Class A installation instructions, sets a distance between a wood stove chimney's outlet and a window.
Chapter 18 does give window distances, in section M1804.2.6. That section is for mechanical draft systems that comply with UL 378, not for a wood stove chimney, so its figures do not carry over.
What does apply to the outlet is its height, set by the 3-2-10 rule below. Every portion of a building within 10 feet counts, the wall with the window in it included. Your building department may ask for more, so ask it before you place the chimney. Our guide on how far a chimney must be from windows and neighbors sets out what the codes say.
What Is the 3-2-10 Rule for Stove Pipes?
It is a height rule for the chimney, not for the stove pipe inside. NFPA 211 sets it, and our Class A installation instructions quote it on page 3.
The chimney must extend at least 3 feet above the highest point where it passes through the roof and at least 2 feet higher than any portion of a building within 10 feet.
On a wall route the chimney often does not pass through a roof at all. It must still clear by 2 feet any portion of the building within 10 feet, the roof included.
Where it passes through an overhang, it passes through the roof, so it must also extend at least 3 feet above the highest point where it passes through.
Our guide to the chimney height above the roof works the rule through on example roofs.
How Is the Outside Run Supported?
A base wall support carries the chimney from below, and wall brackets hold it to the wall above.
For a chimney up an outside wall, page 20 of the instructions says to secure it with wall brackets "at a minimum of 8-foot intervals", and page 23 gives "a Wall Bracket for every 8 feet of chimney height." So fit one at least every 8 feet.
Page 20 adds two cases:
- If the chimney extends more than 5 feet above the top wall bracket or roof flashing, an Extended Roof Brace is required.
- Where the chimney passes an overhang, frame for at least 2 inches of clearance and fit a roof flashing and storm collar. The other option is to cut the overhang away for a 2 inch clearance.
Page 13 limits the brace: only one may be used. The chimney must not extend more than 10 feet above the roofline or highest rigid support, and no more than 5 feet above the brace.
In cold climates, page 5 advises enclosing an outside chimney in a chase, to reduce condensation and creosote and help draft.
Our guide to exterior chimney pipe on the outside of the house covers the outside run in more depth.
What to Check Before You Buy a Wood Stove Window Vent Kit
Settle five things before you order, because each one changes the parts.
- The product you need. For a house it is a through-the-wall or through-the-roof chimney kit, not a window kit.
- The collar size. IRC section M1803.3.3 says a connector shall not be smaller than the flue collar of the appliance, except where installed in accordance with the appliance manufacturer's instructions.
- The wall. Its full thickness, and whether it holds wood framing.
- The height. The 3-2-10 rule against the roof and anything within 10 feet.
- The stove's manual. Its own clearances and floor protection.
Then check the chimney's listing. For a factory-built chimney, IRC section R1005.1 in chapter 10 reads: "Factory-built chimneys shall be listed and labeled and shall be installed and terminated in accordance with the manufacturer's installation instructions."
Section R1005.3 reads: "Factory-built chimneys installed in dwelling units with solid-fuel-burning appliances shall comply with the Type HT requirements of UL 103 and shall be marked 'Type HT' and 'Residential Type and Building Heating Appliance Chimney.'" The exception that follows it in the code covers open fireplaces, not wood stoves.
Our UL 103 HT chimney pipe is listed to that standard, in 6 and 8 inch.
Through the Wall or Through the Roof?
A stove next to a window often points to the wall route, but it is not the only choice. Our kit page notes that a roof route usually allows a straighter vertical run, which can simplify draft when the layout permits it.
Our guide to a wood stove chimney through the wall or the roof sets the two side by side.
Can You Install It Yourself?
Yes, a capable owner can do a standard install by following the kit's installation instructions.
Our Limited Lifetime Warranty on Class A pipe asks that installation follows the instructions supplied with the product. That holds whether the owner or a contractor does the work, and the other warranty conditions apply too.
Ask your building department about the permit and the inspection first. Ask your insurer what it needs to see for a new stove and chimney.
Fit carbon monoxide alarms as your building department and the alarm maker's instructions say. If one sounds, get everyone outside and call 911.
Need More Information?
Our answers on Class A chimney pipe clearance, stove pipe temperatures and codes are in the chimney and stove pipe FAQ. Each route is laid out in our wood stove pipe installation guides.
Send us the wall, the stove and the roof line through a free flue design request, and we will send back a personalized chimney configuration. To talk it through first, ask a chimney specialist or call 888-834-0880.
