Jo wrote:

My early victorian building has a nice stone facade covering what
looks like a messy mix of mortar and rubble.

I want to fit a combi boiler and need to drill a 10cm hole for the flu
pipe. How can I neatly cut such a hole through this type of wall ?

My neighbours did this recently but it seemed that the builder took
three days and from the appearance and size of the resultant hole he
must have done it with a pick axe! I would like to be somewhat
tidier.

With a diamond core drill. I beleive you can hire these. Otherwise you'd
need around 350+ for the gear.

Maker a pilot hole in to out and then core the hole out to in. You'll
want a 107mm drill.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html