Keith Nuttle wrote:
We are planning on putting a mirror to cover the TV hole above our
fireplace. The plan is to remove minimal trim, place shims on the
sides of the existing opening so the mirror is flush with the back
edge of the mantel and the existing trim.

I plan on cutting this backing board so it would fit into the opening,
and holding it in with quarter round or similar.

What would be best for this backing board. MDF, plywood, etc.

Whatever as long as it is reasonably rigid. I used to have a condo with 12'
of floor to ceiling mirrors on the wall (which was drywall).

Should the mirror be bonded to the backer board. If so how?

I would use the black goop that mirror people use for that purpose.
Actually, I imagine most any would work...silicone, acrylic, Liquid Nails,
linoleum paste, etc. Just assure that it is something that won't damage the
silvering.

--

dadiOH
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