What holes do I need through the walls?

[CalvinHobbes]

Sorry for all the questions. I am embarrassed to be asking you so much.

So the builder said that they would charge us £75 per hole through the blocks to put in pipes/ducts whereas if we do the beforehand then it costs nowt.

So trying to come up with a list of holes we will need to factor in and give them pipe or conduit?  So the ashp will need a flow and return as will the MVHR? We will need a hockey stick (still unsure if single phase or 3 phase) exterior light . What other pipes/ducts should I be thinking of? I saw this, could the brickies insert it like they did the meter box? https://www.screwfix.com/p/ip54-weatherproof-outdoor-box-kit/455hh

Edited June 18, 2023 by CalvinHobbes

[eandg]

From memory our ASHP needs 4 penetrations (2*28mm flow and return pipes, 22mm discharge from the hot water tank and a 4mm cable to external sensor), MVHR needs 2*150mm pipes for bringing air in and out. We also gave 2*22mm pipes for hot and cold taps and 4 cables going through for exterior lighting either side of back and sliding doors (lights at front go out with our temperature sensor). You want to plan it all in early too so you can get some airtight grommets (we are using Pro Clima Roflex in appropriate sizes) fitted before your plasterboard goes on. 

[JohnMo]

Outside tap

Door bell

Outside lights, I have one hole front, one rear.

Outside power socket

BT line

Main electric

Power to outside buildings

TV aerial if external 

MVHR X2 holes

ASHP x2 holes (my outside temp sensor is on ASHP), maybe communication cable x1, cylinder thermostat if connected direct to ASHP, 3 way valve power.

UVC overflow

 

[NandM]

For the larger MVHR holes, what's the best approach: put the pipes in as brickies are building (will they hate this/me) or cut through afterwards? I will have 200mm cavities.

[twice round the block]

Outside tap x 2 

1 hot and 1 cold.