Ash Dump Door

The ash dump door is a pivot swing open metal door designed to allow the homeowner to sweep ashes into the ash dump opening. While the fireplace is in use, the door can be closed to prevent hot embers from filling the ash dump. These doors have a tendency to warp and deteriorate over time and require replacement every few years.

In many masonry fireplaces, the ash dump door sits in the floor of the firebox, usually toward the back. Under it is a hollow space inside the base of the chimney called the ash pit. When the fireplace is cool, you open the door, sweep the ashes into the pit, and close the door again. The ash pit is emptied through a separate clean out door, usually in the basement or on the outside of the chimney near the ground. Our clean out door page explains how that door differs from a flue clean out.

Because the door sits right in the fire, it takes a lot of heat, which is why these doors warp and wear out. Building codes call for ash dump clean out openings to have noncombustible doors, metal or masonry, that stay tightly closed except when in use.

• The door is warped and won’t sit flat
• The door is stuck shut or won’t stay closed
• The pivot or frame is rusted or broken
• The door is missing, or the opening is covered with a loose brick
• The frame has come loose from the firebox floor, with cracks or gaps around it
• You notice drafts or smells from the ash pit when the door is closed

A door that doesn’t close properly can let hot embers fall into the ash pit while the fireplace is in use, and it can let air leak into the firebox, which changes how the fire burns.

Inspect. We look at the door, its frame, the firebox floor around it, and the ash pit and clean out below.

Replace the door or frame. We remove the old door and, if needed, its frame, then set the new one in refractory mortar so it sits flat and closes properly.

Repair the hearth around it. Cracked firebrick or loose mortar around the opening is repaired at the same time with refractory mortar made for firebox use. See our firebox joints page.

Check the clean out. We make sure the basement or exterior clean out door closes properly too, so the ash pit stays sealed.

• Only sweep ashes into the dump when the fire is out and the ashes are cold. Embers can stay hot for a long time.
• Keep the door closed while the fireplace is in use.
• Empty the ash pit regularly so ashes don’t pile up to the door.
• Store removed ashes in a metal container with a tight lid, outside and away from the house and anything that can burn.
• Never use the ash pit to store anything else.

For more tips, read our guide on how to remove fireplace ash, or see the full anatomy of a chimney.