What Kind of Insulation to Use Around My Heatilator Gas Fireplace?

When installing a fireplace, insulation should be a priority and not an afterthought. Whether installing a Heatilator gas fireplace or another brand, you will need to make an assessment of the insulation currently in your walls and determine if more is needed, but you cannot have insulation along the entire chimney and fireplace. Knowing where to put insulation and where to keep it out can keep the fireplace heat from leaking out and prevent a fire.

Modern fireplace.
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What Kind of Insulation to Use Around My Heatilator Gas Fireplace?


The Heatilator is a fireplace brand offering gas, wood and electric fireplaces. The company also has fireplace inserts and stoves. Its gas fireplaces install directly into the existing brick fireplace with the flue pipe going up the chimney or into the wall. The same rules apply for insulating around the fireplace or chimney with the various gas fireplace models from Heatilator and other companies.

Importance of Insulation

Placement of insulation for a fireplace is critical to the safety of your home. Insulation around a gas fireplace metal chimney can catch on fire inside the walls or attic where it will continue to burn until it might be too late to extinguish it to prevent serious damage to your home. Insulation inside the wall around the vent for a wall-mounted fireplace is also forbidden because it can catch fire. To prevent cold air from seeping into your home from the outside, the gas connection is one of the only places where you can add insulation safely around your fireplace. The other place depends on the location you choose for the fireplace vent.

Insulating Gas Fireplaces

Heatilator gas fireplaces can be vented through the top or the side. A built-in insulation basket is included with the fireplace around the vent. If you are venting the fireplace from the top, you need to cut out a hole for the vent from the insulation and leave it in place, but remove the entire piece for side venting. Unfaced batt insulation may be pushed into the opening between the gas supply pipe and the access hole. The fireplace itself is heavily insulated and you should not install insulation into the walls surrounding the firebox.

Chase Insulation

Insulation in the chimney should never come in direct contact with the vent pipe because it poses a fire hazard. If cold air seems to be coming into your home through the fireplace, you might want to install a chase around the chimney on your roof or check the insulation in the existing chase. This box surrounds the chimney above the roof where it insulates the chimney against cold air. These are frequently used in Northern climates with bitter winters. Insulation in the chase should never come within two inches of the chimney, but batt insulation needs to be cut to fit around the firestop in the chase.

Attic Insulation

As the chimney pipe moves through the attic, you must put the attic insulation shield provided with your Heatilator fireplace around the vent pipe. This will prevent the insulation in the attic from touching the vent pipe and posing a fire hazard.