On 10/05/2019 22:26, R D S wrote:
On 10/05/2019 21:35, Chris B wrote:
Can anybody suggest a sum that would be reasonable for this job as a
"little extra"
How long is it taking them to drill other holes?

In my experience core drilling can take an inordinate length of time but
that said the last one I did took about 10 mins and was a relative joy.

It depends on the wall. Mine is Victorian hand made bricks and 3 bricks
thick and with almost round flint pebbles in. It took the guy who put in
my vent for the wood burning stove about 3 hours and 2 core drills.

It was incredibly difficult to get through because of the little pebbles
jamming up the saw teeth and the bigger ones rotating in the matrix.

--
Regards,
Martin Brown