Thinking insulation fixes air leakage instead of sealing duct first

Insulation does not fix duct leakage. Seal/test the duct first, then insulate once the air boundary is ready.

Stop if

• Before I insulate this, is the duct sealing/testing cleared? I don't want to cover a leak path.

Watch out

• Do not use insulation as an air seal.

Check

• Check whether the duct joint/collar/seam is sealed before wrap.
• Look for missed backsides and hidden corners.
• Ask if pressure/leakage testing is required before insulation.
• Hold wrap if insulation would hide an unsealed leak path.

Steps

• Check whether the duct joint/collar/seam is sealed before wrap.
• Look for missed backsides and hidden corners.
• Ask if pressure/leakage testing is required before insulation.
• Hold wrap if insulation would hide an unsealed leak path.

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