Compression versus Pushfit

[Belboz]

Hello all,

Quick one [!!]

Replacing rad in bathroom. New rad is different size. Will therefore need to drop the tails from the new rad and then connect under the floor boards to the existing rad pipes. The existing floorboards will be covered with a floating floor so that I can still access the pipework underneath should anything go wrong.

Anyhow, as I see it there are 3 options;

(1) Use a compression elbow from each of the rad tails joined to a right-angled bent pipe then straight compression joints to the existing two pipes.

(2) Use a pushfit elbow from each of the rad tails then plastic pipe to pushfit straights joining to the existing pipework

(3) Same as (1) but using plastic pipe with inserts joining the two 'new' compression joints.

Reason I ask is that I always feel that compression joints are 'safer' than the plastic ones but I have never used compression joints with plastic pipe and using plastic pipe makes the pipe run easier to sort. The easiest would be option (2) but I would appreciate your views on how 'safe' this arrangement is.

By the way, I suspect the professionals on here will say that the best method is solder fittings............

Many Thanks

 

[bengasman]

Simple answer: never ever should you use compression fit connections that are not open to inspection e.g. under a floor.
You may be able to access them to repair if need be, but that will only be after the damage to the ceiling below and the heating system has been done.

 

[Belboz]

Thanks.

I have only ever used these fittings where I have an inspection panel or similar access.

I suppose that means getting a plumber in.............

 

[Richard C]

By the way, I suspect the professionals on here will say that the best method is solder fittings............

I wouldn’t use anything else, especially on my own property & if for any reason I couldn’t solder, I would only use compression; old fashioned maybe but I just don't trust pushfit. Using solder fittings really isn’t difficult, you just have to make sure everything is really clean & well fluxed; a little heat & it’s done.

 

[narcosis]

I would probably say that soldering is easier than compression joints, its a piece of cake, you could have a play with some gaf pipe and fittings for practice.

Neil

 

[longdogs]

It doesn't matter which method you go for so long as its done properly. If don't feel comfortable with soldering then buy some John Guest Speedfit connections ( you can connect them copper to copper without inserts ) make sure they are fully inserted and tighten the outer plastic nuts. Cut pipes with a good tube cutter and not a hacksaw. If you are still worried about them leaking then leave the floorboards up for a day or so, so that you can check. Fitted correctly they will not leak.

 

[GeorgeBramwell]

Simple answer: never ever should you use compression fit connections that are not open to inspection e.g. under a floor.
You may be able to access them to repair if need be, but that will only be after the damage to the ceiling below and the heating system has been done.

The same can be said for pushfit. Quality compression joints smeared a quality compound will last and last.

 

[DP]

What happens when nthe grab ring corrodes, O ring goes hard, plastic pipe starts leaking at the joint be it compression or pushfit or the palstic pipe is nibbled by rodents. Have encountered each scenario.

Also good practice and in some cases regs state solder under floor and other tytpe of fitting where accessible.

Cannot imagine an access panel at every joint in the plumbing system

 

[GeorgeBramwell]

What happens when nthe grab ring corrodes, O ring goes hard, plastic pipe starts leaking at the joint be it compression or pushfit or the palstic pipe is nibbled by rodents. Have encountered each scenario.

Also good practice and in some cases regs state solder under floor and other tytpe of fitting where accessible.

Cannot imagine an access panel at every joint in the plumbing system

I have had the same problems with pushfit as well. It is good practice to use solder joints under floors. Nothing I have ever read has said it is mandatory. Quality compression joints are good, like Conex or Kutelite.

 

[Belboz]

Thanks everyone for the sound advice.

 

[Frogit]

Modern pushfits are fine. If you dont like the look of the big plastic ones there are the slimmer copper or brass ones out there now that look great. Just make sure you mark the pipe at the depth the fitting has to go into, to be sure you have the pippe fully in on assembly.

 

[Whitespirit66]

Pushfit and plastic pipe is fine, but only if you're careful about fitting it correctly. Make sure that the ends of the plastic (it must be barrier pipe in your case) isn't scored or scratched and you have put a support insert into the end of the pipe. Also make sure that the ends of any copper pipes inserted into pushfit fittings is undamaged, deburred and perfectly circular. I have seen pushfit fail because the end of the copper pipe was very slightly oval.

Don't let the doubters put you off pushfit, after all, most new housing built today has nothing else.

 

[gaspro1981]

compression any day of the week
imho there are too many flaws in pushfit as already detailed in this thread

 

[Deleted member 105431]

Don't let the doubters put you off pushfit, after all, most new housing built today has nothing else.

most newbuild houses also have the worst plumbing and heating badly installed by cowboys.