On 23/04/2021 17:58, John Rumm wrote:
On 23/04/2021 15:15, PaulJoe wrote:

The house I'm moving into needs air vents adding under the conservatory
to ventilated the suspended flooring in the ground floor. Can anyone
give me an estimate of cost please?

Well when I needed to add some under floor ventilation here is cost me
about £3 / air brick and probably 10 mins work each.

It'll obviously need the con floor
lifting and replacing. Thanks!

Why obviously? Normally air brick style vents are fitted from the outside.

Typically you would remove a brick, then mortar in a vent in its place.

When we had extra air vents added to the house wall the polystyrene ball
insulation poured out when the brick was removed! The OP's conservatory
wall might have the same issue.

Depending on the outside wall finish you may be able to take out a whole
brick with a brick removing chisel, or if rendered etc, just chop in the
perimeter with an angle grinder, and then use a chisel bit in a SDS to
knock out the waste.

Assuming the wall is double thickness separated by a cavity, getting to
the inner brick to remove it isn't quite so easy (especially if the
cavity keeps filling up with polystyrene balls!). And no doubt Sod's Law
will be operating, so a central heating or water pipe will be just
behind that inner brick, preventing it from being pushed in.

--

Jeff