A wood-burning fireplace insert can enhance your home’s heating capacity and reduce energy costs. The process requires careful planning and execution, but with This Old House plumbing and heating expert Richard Trethewey and expert installer Matt’s advice, you can get the best return on your investment.
Wood Stove Fireplace Insert Safety Considerations
Protect your home and family by keeping these safety tips in mind during installation:
- Keep proper clearance between the insert and any combustible materials.
- Verify that the chimney and flue are in good condition and properly sized for the insert.
- Install carbon monoxide detectors near the fireplace and throughout your home.
- Have a certified professional inspect the installation before use.
- Follow all manufacturer’s instructions for operation and maintenance.
Preparing for Fireplace Insert Installation
Before you start the installation process, be sure to address any signs of damage or wear in your existing fireplace. You should also measure the dimensions of your fireplace opening to ensure the insert you choose will fit properly.
Next, gather a few tools and materials that you’ll need:
- Acetylene torch
- Angle grinder
- Caulk gun
- Chimney pulling cone
- Cold chisel
- Hammer
- High-temperature silicone sealant
- Nut driver
- Pipe wrenches
- Rope
- Screwdriver
- Sledgehammer
- Stainless steel vent liner
- Surround panel
- Tin snips
Preparing the Fireplace
To prepare the fireplace, Matt removes obstructions that might interfere with the insert. He uses an angle grinder to remove protruding bricks and grind down uneven surfaces. Then, he installs a 110-volt power outlet for the insert’s convection fan.
Finally, he caps off the fireplace’s ½-inch gas line with pipe wrenches and a half-inch cap. This step mainly prevents gas leaks, but old piping with holes in it can also become a log ladder.
Installing the Vent Liner
The vent liner runs to the top of the chimney to safely channel smoke and gas out of your home. It has several layers: the innermost layer is stainless steel, followed by a layer of insulation and an aluminum outer shell.
Preparing the Chimney
Before installing the vent liner, you must create a clear path through the chimney. In the simplest case, this might involve chiseling out more obstructing bricks or clearing debris. For Trethewey’s project, though, he needed to remove the existing damper since it was welded to the top of the original fireplace.
Inserting and Connecting the Liner
Once the chimney is prepared, you can begin inserting the vent liner. Matt attaches a pulling cone to the end of the liner and then ties a rope to the cone. He drops the rope down the chimney so Trethewey can guide the liner into place. Then, Matt trims the vent liner to the appropriate length.
Once the liner is in place and cut to size, there are a few connections to make. Matt removes the pulling cone from the vent liner and attaches an adapter elbow to the end of the vent, tightening it in place with a nut driver.
Before cutting the insert, Matt applies high-temperature silicone sealant around the top edge of the flue tile and installs the chimney cap.
Installing the Fireplace Insert
With the vent liner in place, Trethewey and Matt carefully slide the insert into the prepared opening. Once it’s centered and leveled, they reach into the fireplace and plug the power cord into the outlet they installed earlier. They also screw the adapter elbow to the top of the fireplace insert and secure the connection.
Finally, they’ll attach the surround panel onto the insert. This both complements your room’s design and helps to seal gaps between the insert and existing opening.
