You can't weatherstrip the damper (that would be a fire hazard), so build a rustic reclaimed wood fireplace insert to stop drafts. Easy to follow step-by-step tutorial.
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Keep the Cold Air Out — No more shivering through movie nights because of a chilly draft. Get cozy in seconds while saving valuable energy year-round
Choice Home Goods Magnetic Fireplace Cover - Cozy Wood Design Fireplace Draft Blocker - Fire Place Cover for the Living Room - Fireplace Insulation
Choice Home Goods Magnetic Fireplace Cover - Cozy Wood Design Fireplace Draft Blocker - Fire Place Cover for the Living Room - Fireplace Insulation Draft Stopper - Fireplace Blanket - 39 x 32” : Home & Kitchen
Build a Fireplace Insert Draft Stopper - Pretty Handy Girl
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Build a Fireplace Insert Draft Stopper - Pretty Handy Girl
My Fireplace is Too Drafty
woodshop Archives - Small Boats Magazine