Pipe & Drill Size

[Skavenger]

Hi, 2 questions:
1. I am fitting a new kitchen and will be using the existing water pipes for now but as these are buried in the floor I want to run new pipes behind the cupboards ready for a later project when we bring the boiler downstairs, what size pipe work should I install 15 or 22. It will supply a sink, outside tap and washing machine, the run will be 5 - 7 metres.
2. I need two drill two holes for the pipes should I get a 16mm or 14mm masonary drill, I thought a 15 as a masonary drilled holes is never perfect. All depends on the size of pipe of course. The hole will be through a cavity wall.

 

[mickyg]

drill it big enough to sleave the pipe with something else if its in a cavity wall, I normally use 22mm plastic tube.

 

[kirkgas]

25mm masonary drill will allow you to sleeve 15mm copper/plastic through the wall

 

[muggles]

Ditto, 25mm so you can sleeve the hole using 22mm pipe then run the 15mm inside that (this protects against corrosion and stops the cavity filling up with water if you get a burst in the wall).

 

[Skavenger]

OK looks like a 25mm Masonry Drill then, any tips on drilling through a cavity wall roughly 350mm wide, should i go straight through with a 25mm x 400mm Masonry Bit or sink a pilot hole first with a smaller 400mm Bit.

 

[Mark Br]

OK looks like a 25mm Masonry Drill then, any tips on drilling through a cavity wall roughly 350mm wide, should i go straight through with a 25mm x 400mm Masonry Bit or sink a pilot hole first with a smaller 400mm Bit.

Personally I always work up in sizes rather than trying to drill 25mm in one go.

 

[mickyg]

as above pilot it first, otherwise your gonna take a chunk out the wall when it comes through. You can pilot through. Then drill half way from one side and half way from the other, avoiding damage to walls.

 

[Skavenger]

What size pilot for a 25mm Drill, 16mm or less?

 

[muggles]

Personally I'd go from inside to outside with a 10mm, then from outside to inside with a 16mm then the 25mm. This should minimise damage to your rendering/brickwork on the outside