Are you planning on getting a wood stove? Apart from installing this appliance, you will need to get a chimney pipe affixed as well.
Although this seems like a tough job, you can perform this project yourself. All you need to do is follow this guide on how to install a chimney pipe like a pro.
- Chimney pipe
- Wood stove pipe
- Ceiling support box
- Adjustable roof flashing
- Storm collar
- Chimney rain pipe
- Spray paint
- Tin snips
- 5/16 nut driver
How to Install a Chimney Pipe (Through-the-Roof)
Step 1. Measure the Chimney’s Internal Diameter
To get this figure, all you need to do is check the flue collar on your stove. It’s crucial that you pick the correct size. If you choose a smaller one, you’ll be beset with poor draft and more creosote.
Remember: creosote is a probable carcinogen. Studies show that it may cause skin cancer. In fact, simple exposure to this can lead to rashes, redness, burning, irritation, and itching, to name a few.
Step 2. Plan the Chimney Pipe Location
Ideally, a chimney pipe should be installed in your house’s interior. If you place it near the exterior, there will be less draft but more creosote formation.
Additionally, a straight-run installation is best. But if this is not possible and your pipe will need to avoid obstructions, then you have no choice but to place offsets.
Pro tip: If you’re living in the United States, then you’ll have to follow strict local building codes when installing a chimney pipe. Here, only two offsets are permitted per installation – and the elbows should not measure more than 30 degrees.
Step 3. Pick the Right Installation Type
There are two configurations available: through the roof or through the wall. You will need to determine how you want your chimney placed to get the right materials.
For example, if you decide to go with a through-the-wall configuration, you will need to purchase additional items such as wall straps, tee support, tee with cap, and wall thimble.
As such, I’ll be discussing the cheaper and easier way of chimney installation – via the through-the-roof method.
Step 4. Calculate the Required Number of Pipe Lengths
When calculating the number of pipe lengths, you will need to consider these pointers:
- The chimney must be 3 feet longer than the highest point (where it passes through the roof.)
- The chimney must be at least 2 feet higher and 10 feet away from the roof line.
- Should you wish to have a chimney that goes 5 feet above the roof, you will need an extended roof bracket to make it stable amidst the elements (such as snow and wind.)
These measurements help regulate drafts or the movement of gases in the chimney system. Remember: this is influenced by chimney height, the temperature of gases, and the outside air currents, to name a few.
If your chimney does not meet the above-mentioned specifications, then it will be difficult for you to keep a fire going. Worse, smoke will just end up rolling out of the wood stove (instead of outside the chimney.)
All in all, when calculating the lengths, you need to factor in the above-mentioned height requirements and subtract the measurement of each joint. That way, tight-fitting joints can be overlapped as needed.
Typically, a straight-run insulated chimney pipe (at sea level) will measure 10 to 15 feet on top of the appliance. And, should your chimney require a tee or an elbow, the measurement will be 30% to 60% longer than usual.
Likewise, don’t forget to measure the roof pitch, as this will help you determine the right type of flashing.
Step 5. Locate and Cut the Chimney Pipe Center Point
Now that you have determined where your chimney pipe will rise, it’s time to pinpoint the center of this area.
With the help of a ceiling box, label the area where you’ll make a cut. Use a Sawzall to cut through this area.
Mount the ceiling joists with the use of the support box’s two joints.
Head to the attic and slide the box through the opening. Attach it to the joists.
Step 6. Determine the Roof Area to Be Cut
After punching through the ceiling, it’s time to mark the roof area. To do this, you need to slide a level underneath a section of the stove pipe.
Next, run a screw on the roof deck area where the chimney will exit. This will help you determine where to cut when you’re on the roof.
Step 7. Mark and Cut the Roof Area
Place the adjustable roof flashing on the screw you’ve placed on the roof. You can use this as a stencil the mark/spray paint the area.
Again, using the Sawzall, cut through this marked part of the roof.
Step 8. Put the Adjustable Roof Flashing
Cut the top-half nails of the flashing with the Sawzall. Using tin snips, cut the shingles two inches back on the top half.
Put silicone on the bottom area of the flashing. Next, slide it under the top part of the shingles and screw the flashing to the roof. Don’t forget to apply silicone to the screw heads and the top part of the flashing.
Pro tip: You can also install the flashing through traditional caulking. To do this, you need to apply half an inch of this material on the base and another half across its circumference. Just make sure to press the caulked flashing down firmly to get it in place.
Step 9. Install the Chimney Pipe
Locate the pipe area with recessed insulation (male end.) To ensure a seamless transition from this area to the single-wall pipe, you will need to use sheet metal screws to affix the universal pipe adapter to the male end.
Once the adapter is installed, you may bring down the first section of the pipe carefully through the flashing and support box.
Step 10. Affix the Storm Collar and Chimney Rain Pipe
Before getting down from the roof, make sure to install the storm collar first. You can do this by placing a silicone bead where the collar and stovepipe meet. Use a 5/16 nut driver to affix the chimney rain cap on the pipe.
Remember: These materials need to be installed for they help prevent the entry of water, insects, or debris into your chimney pipe system.
Step 11. Install the Single Wall Stovepipe
When using a telescoping chimney pipe, join the female end with the male end of the pipe. Make sure that the latter part is pointed down (towards the stove.) That way, the drips will just fall back into the stove where they will be burned later on.
Again, make sure to use a level to ensure a straight installation.
Last but not the least, screw the trim collar around the ceiling support box. Insert the pipe into the collar and you’re done!
Why is Through-The-Roof Method Better Than Through-The-Wall Chimney Installation?
Apart from the need for more materials, a through-the-wall configuration is deemed to be less efficient. It reduces draft since the outside temperature can easily cool the chimney gases. This leads to condensation, and eventually, creosote formation.
What are the Two Types of Chimney Venting for Wood Stoves?
Depending on what you want to achieve, you have two choices:
- Air-cooled chimney. As the name suggests, this ‘big’ fixture helps cool the home. That’s because it allows the air from outside to flow into the system.
- Insulated chimney. This product is insulated with either fiberglass, ceramic blanket, or mineral wall. This can help maintain safe temperatures in your home, especially if you plan on installing a wood stove.
Single vs. Double Wall Stovepipe: What’s the Difference?
When installing a chimney pipe, you will be met with two options: using a single or a double-wall stovepipe.
Similarity-wise, both are painted in black for this is the color that best withstands high temperatures. As for thickness, both models come in 22 and 24 gauge.
Single wall stovepipes, however, should be placed at least 18 inches away from a combustible wall. Unless it is protected or has a heat shield installed, you may reduce the distance to an acceptable 9 inches.
Double wall or clearance stovepipes, on the other hand, have an inner wall that is made of stainless steel. Since this layer serves as insulation, a double wall pipe only needs to be placed 6 inches away from combustibles.
To install a chimney pipe, you need to:
- Measure the chimney’s internal diameter
- Plan the pipe location
- Pick the right installation
- Calculate the number of pipe lengths
- Locate and cut the area in the ceiling
- Determine the roof area to be cut
- Mark and cut the said area
- Install adjustable flashing
- Install the chimney pipe
- Place the storm collar and rain pipe
- Install the stovepipe
Now I know that there are a lot of steps, but they’re fairly doable! And, in case you have any questions, I’ll be more than happy to answer them below!