One of the major hurdles with using any type of plastic material, including PP-R, is the tendency to expand when exposed to heat. That's why we developed our faser-composite technology.
Our pipes are extruded with a middle layer that reduces expansion by 75% by blending glass fibers with the PP-R, which reinforces the pipe and restricts expansion and contraction. This faser-composite layer does not require any modification to the fusion process, so installations stay fast, look great, and require fewer supports.
Aquatherm's faser-composite pipes have about the same expansion rate as copper tube but with much more flexibility, so you can use fewer and smaller expansion controls. Aquatherm pipes can even be buried without any expansion controls or thrust blocking, as the weight of the soil will restrict any movement.