Copper pipework installation and lagging

28 Apr 2006
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United Kingdom
Could someone help solve an argument.

What is the correct sized lagging used after installing underfloor 15mm and 22mm copper pipe on the flow and return heating pipework?

Is it 9mm for both?

Also what is considered the best method of securing underfloor copper pipes?

My view is that, all underfloor copper pipework should be secured and lagged by using plastic pipe clips and secured with plastic ties to the lagging. Whilst others think using galvanised metal straps to secure pipework is ok on top of the lagging?

I have always been shown that plastic pipe clips should always be used?

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If they are to be screeded over then no securing is necessary plus the insulation will hold them.
Thicker the insulation the better though the heat from the pipes is usually captured within the building envelope.
Sorry I should have mentioned the copper pipework was laid under a wooden floor attached to wooden joists.

The void area below the wooden flooring is just over 2.5 feet in depth
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The thicker the better in my opinion for lagging pipework under the ground floor. 9mm is pretty much the thinnest insulation available so i would go for at least 13mm. Any pipework under the first floor and above doesn't need lagging as any heat loss is useful heat. ( obviously any pipework in lofts should be treated the same as pipework below the ground floor.

As far as clipping/strapping insulated pipework goes. Your method is fine. Many installers will use many different methods, but at the end of the day. As long as the pipe is secured and well insulated then you will be fine

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