John Guest underfloor heating pipe clips and a fast fix fixing tool. This is an excellent fixing tool that allows you to fix the clips stood up and saves crawling around. The clips are superior to Staples as they space the pipe slightly above the insulation, so allowing the screed to fully encapsulate the pipe, and therefore more efficient heat transfer. Bought this used to do my extension and now passing it on, along with half a bag (48) clips.
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