DIY Doctor UK DIY Forums

I have a fireplace that was blocked up with hardboard.

Looking behind the board, i have a bruick arch, but also a very thin (10mm thickness) wooden beam right below the arch. This beam is keyed into the brick at either end - see attached image

This beam seems far too flimsy to be a lintel - the load is surely taken by the arch, but the fact it is keyed in seems odd. Might it have been put in to support the arch during construction, and simply never removed?

I don't need to remove it either, but would like to understand why it is there...

Could you post a better photo the one attached is too close up.

From your description it does look as though it is thin so that it will bend to make a former and then been left in place as you suggested.

This shows it a little better

You can see the arch, and the beam, but also some mortar filling the gap between the two...

Sorry I thought you meant a curved arch.
You are sure it is timber and not iron or steel? I looks as though it's an old building, if so then it was the practice in days gone by to use a thin piece of iron plate to support a brick arch such as this. If it is timber then I cant see how it would survive the fires so close.

Yes, certainly wood. It is possible it was only put in when the fireplace was bricked in, but then it is odd that it was keyed in and mortar added...