Running copper pipe questions...

[adam81]

Hi,

I need to run a pair of feeds for my hot and cold water supply to a new shower.

The best plan of attack I see is to notch out the joists that it will run perpendicular with and then run the remaining distance parallel with the joists.

I've looked at notch limits and such, and also seen suggestions that gas pipes need to run under joists, can the water pipes though be bracketed to the side of the joist as in my diagram?

Putting 3mm steel plates above the notches is fine, but there will be an elbow where the pipe then goes downwards to the height it would remain for the parallel run.

Of course I could drill holes in the joists as well, and then the same question remains as to the parallel run. A notch would take 2 x 15mm pipes as my joists are 7x2, but drilling would mean they are offset from the feed would it?

Is there a limit they need to be from the floorboard above or the ceiling below? There is a lot of flex that has been drilled through the centre of the joist so is the safest way to run it under these holes or above?

At the end of the run they will come down and be chased into the blockwork behind a dot and dab wall.

Cheers for any pointers
Adam

 

[dcawkwell]

If this is retro fit.
You can notch 1/8 of the joist.
As regard running with the joist just pull the pipes across people rarely
worry about fixing them to the joists and plastic pipes allow you to pull
them through easily.
If this is ground floor you can use plastic and simply pull them under the joists job done in 5 minutes without any notching.

 

[calorific]

This is where a pipe bender earns its crust

 

[adam81]

Yeah I have pipe bender rather than elbows, but I was more concerned about the overhanging pipe that is unprotected (without the 3mm plate) for the few inches before it goes down again.

It is a retro fit yes. Is there nothing that says they need to be a certain distance from the floorboard like there is for electrical cable?

I'd read I could notch 1/6 so with 7 inch joist I'd be pretty close if I go with 22mm for the hot feed.

It's 1st floor but I have most of the ceiling down below it anyway. If I run PEX the crimper will cost me as much as the pipe I think..

 

[calorific]

notches

No need to worry about the bit unprotected - the metal plate is purely to prevent accidental nailing of the board to the joist. Also, no need to worry about how high to lay the pipes. Cables have specs to prevent them being covered with insulation which might lead to overheating.

 

[adam81]

Cheers calorific,

When running the new pipes is it worth running 22mm for HW and 15mm for cold. Both will be independent feeds from stored water in a gravity system.

Just the mixer shower I think I will end up with requires 15mm connections so the 22mm will be reduced at that the valve anyway

Will I notice a better flow?