What to Do With an Unused Chimney

Problems with an unused chimney

Plenty of fireplaces in Florida homes go years without a fire. The problems with an unused chimney come from what still reaches it:

• Water: rain through a missing cap or cracked crown rusts the damper and soaks the masonry.
• Animals: birds, squirrels and raccoons nest in an open flue, and nests block it.
• Smell: old soot holds moisture and smells sour on humid days.
• Drafts: a leaky damper lets cooled indoor air out and humid outdoor air in.
• Hidden wear: nobody notices a cracked crown or loose flashing until a stain appears.

Cap off an unused chimney

The simplest step is a screened cap on every flue. To cap off an unused chimney this way keeps rain and animals out while leaving the flue open, so the fireplace can still be used later after a sweep. A top-sealing damper goes one step further: it closes the top of the flue with a gasket and opens with a cable from the firebox.

Seal an unused chimney for good

If you will never use the fireplace again, you can seal an unused chimney at the top with a solid cover fixed over the flue, and close the firebox opening below. Leave a small vent opening as the cover maker recommends so moisture inside can still escape, otherwise the masonry stays damp. The crown, flashing and brick still need checking from time to time, because the stack is still on your roof.

How to close off a fireplace from the room

How to close off a fireplace from inside depends on what is behind it. A tight glass door set, an inflatable flue plug or a decorative panel over the opening all cut drafts. Never block the opening of a fireplace that is connected to a working gas appliance, and remove any plug before lighting a fire.

Before you use it again

An unused chimney should be swept and inspected before the next fire. Nests, a rusted damper or a cracked flue tile are common after years of rest. Our chimney cap replacement page covers caps and screens in more detail.