Plumbing for garage.... plastic or copper?

[Stephen]

Hi, I have a garage that shares one wall with the house.

I have brought out in copper the hot and cold through the party wall between house and garage. It projects into the garage by about 6 inches to a pair of stop valves. (so I can turn off water to the garage during the winter.

The plan is to put a sink in.

Given that there is no heating in the garage (ts of brick and redland tile construction. Ther risk of pipe freezing is higher than in the house.

Obviously I will be insulating the pipes.

My question is as follows: which is less likely to burst in cold weather, Copper or PLastic pipe?

Regards

Stephen.

[Tim Watts]

I have had a bit of temporary JG Speedfit feeding a tap outside dropping down the outside wall for 3 years and it did not seem to suffer during the winter.

Plastic will have enough give to cope with freezing expansion.

Copper will generally survive too - but the joints may not.

[Tim Lamb]

In message , Stephen writes

My vote is for plastic.

However, pipe routing may be more important. If you arrange for the pipes to rise significantly all the way to the taps, you should be OK anyway. Concentrated cold draughts also worth avoiding.

[terry.shitcrumbs]

I'd be surprised if such a short run from the warm environment of the insid e of your house would allow the pipes to get down below freezing in anythin g but the most extreme of winters. With copper, as a good thermal conductor and with lagging, I would imagine the chances are pretty much zero.

Entertaining the notion of extreme winters to come, perhaps similar to the one we had four years back, you could use a line heater to keep pipe conten ts in liquid form. That's what I did in my garage after the copper burst in multiple locations on long, unlagged runs, during that winter four years a go.

At the same time as the pipe burst described above, a temporary Portakabin office that I was in at work had its plumbing fail. This was plastic pipe a nd the pipe itself remained intact, but the push fit joints were forced off by the freezing. My guess is that the best approach for resistance to free zing damage would be plastic pipe with copper joint inserts and compression fittings.

All the best.

Terry.

[Capitol]

I'd use copper, but also fit a radiator from the house heating. My outside tap is copper plumbed for a couple of uninsulated feet and hasn't failed in 40yrs.

[News]

In message , Stephen writes

Probably a bit late now, but could you not put the stop valves on the house side of the wall, so removing the potential problem? Having said that, our outside tap is fed via plastic pipe, and has always been fine, he says, touching wood. I turn off the stopcock during winter, and leave the outside tap open, but sometimes forget. We are in Aberdeenshire, and the plastic pipe goes through a solid granite wall, three feet thick.

[Roger Mills]

Late or not, the stop valves *definitely* need to be inside the house, and not on the cold side. If they're in the garage, you could have a major leak if the pipes burst on the supply side of the valves.

If you do that, it doesn't matter what sort of pipe you use - just turn the stoptaps off and leave the garage sink taps open. Ideally, also put drain taps at the lowest points.

[Clive George]

I've put quite a few patches in copper pipes now. Not the joints, the pipes.

(can't drain that bit fully, house has no heating when we're away. It's now been redone in plastic with more sensible pipe runs now)

[Stephen]

Pipe routing will be *interesting*

The two H&C pipes come out at ceiling level in the garage (they come through from between the bedroom floor and lounge ceiling)

So the pipes have to traverse the garage for 2.5m to a corner and then drop down to the floor for 2m down said corner, and then back across under the sink 1m and then a short length up to the taps.

[Stephen]

There would be a pipe total run length of 5.5m to 6.0m from where it enters the garage and ends up at the taps

I am hoping to avoid trace heaters if I can use a passive solution instead

At least with plastic pipes. depending on the routing you can use less joints compared to copper......

[Stephen]

It would have to be a hell of a massive radiator as the garage is a single skin wall, there is no ceiling to speak of, there is no loft or rafter insulation and the door is a metal single skin door...... and thats just the fabric heat loss.....

As for ventilation heat loss, the roof is open at the eaves and there are no draught excluders around the garage door.

[Stephen]

The H&C pipes run between the ground floor ceiling and the first floor floorboards.

A bedroom and a lounge is adjacent to said garage. putting stopvalves on the inside would mean valves on the wall near the ceiling in lounge or near the floor in the bedroom..

Thats why as soon as the copper pipework entered the garage, I then fitted stop valves to this. I can insulate the pipes between the wall and the stopvalves.

Having said

[Stephen]

See my reply to previous poster

I plan to put in draincocks anyway.

[dennis]

Plastic will survive being completely frozen, the copper pipes and stop taps will not!

Put the stop taps inside and run plastic.

[Capitol]

Sounds like you've just found the next project then!

[Roger Mills]

Why not put them under the floorboards, and make a little trap-door for access?

Insulation only delays the onset of freezing - it doesn't prevent it.

[Roger Mills]

That is true but, if they show, they don't look very good because its quite difficult to keep them straight. Copper pipe with soldered elbows, etc. will look far better.

[Tim Watts]

It would be enough to delay it until spring :)

[Stephen]

That would ruin the laminate flooring above it or the ceiling below it.....