'Twas Mon, 28 Oct 2002 16:48:52 +0000, when Grunff
enriched all our lives with these worthy thoughts:

AFAIK, that *is* what the are, and if your concrete is indeed only 4"
wide, then it would almost certainly split.

4" *wide*??? I assumed that was an error and the OP meant 4"
*thick*. At 4" wide, it's doing well holding itself together!

In that case, I'd use frame fixings to fasten a timber batten
to the concrete and then fix the GH to the battens. If the frame
fixings are at, say 500mm centres, that should be adequate to anchor
the battens and the GH.

--
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