I was adding some insulation foam into our fireplace as a way of stopping drafts from the chimney. It's obvious that it's installed so we won't ever have it there when a fire is lit (we have not yet used the fireplace since buying the house, though we have had it inspected and swept).

However, when installing it, I discovered that between the fireplace facia and fireplace itself around the edge of the opening into our lounge is stuffed some fibreglass insulation. It looked from what I could see that it was somewhat loose and I wondered if it too should be removed before lighting a fire in that fireplace? I can't be sure but I could see that it would certainly get very hot there and may even come into contact with the flames. Is this normal or should I remove this insulation?

  • 2
    Can you provide a picture? I'm still confused on where you're seeing the insulation. As per inspectionnews.net: "Some metal fireboxes with a metal smoke chamber require insulation in this area to allow for expansion and sealing of the transition between the vitreous clay flue tiles and the metal smoke chamber flue tile receiver."
    – Mike B
    Dec 7, 2010 at 21:20
  • @Mike: I'll see what I can do. However, that does sound like what this might be.
    – Jeff Yates
    Dec 8, 2010 at 3:24

1 Answer 1


This is sometimes rock wool insulation. Even if not, fiberglass insulation is non-flammable, as long as no vapor barrier is used with it.

Installation of fireplace doors and fireplace inserts usually includes such insulation.

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