Minimum bending radius
The minimum bending radius of unsupported Polybutylene pipe is 12 times the pipe diameter. Bends can either be supported at each end of the bends using pipe clips where possible. Alternatively, bends can be supported by a bend former (PB6315 or PB6322) where only one screw hole is required, and the minimum bend radius is 8 times the diameter.
|Minimum bending radius|
|Pipe Diameter (mm)||10||15||22||28|
The main benefit of using Polypipe polybutylene pipes is that the pipe flexibility allows pipe to be cabled through the fabric of the building offering the following advantages.
New build applications
- Allows 1st floors to be laid before plumbing is installed. Plumbing can be installed through holes drilled in joists.
- Site safety is enhanced as pipework can therefore be installed from below.
- Post installation repair work is reduced, as expansion noise due to trapped pipes does not occur, and leaks due to nailed pipes are avoided.
Position of notches and holes
Alterations to existing systems
- Less disruption to property as floors and carpets may not have to be removed in some rooms.
- Kinder to building structure, as existing joists may not allow further notching.
- Pipes can be cabled around existing obstructions.
- Safety is enhanced as no naked flames are required.
Polybutylene pipe provides installers with the flexibility of installing pipes through both holes and notches in joists, choosing the most appropriate method. Building Regulations provide instructions on the drilling and notching of floor joists however an example is shown below.
Size of notches and holes
All pipes should be correctly supported using either nail-in, snap-fit or bulldog clips. Where required spacer pieces are available for the snap-fit clips. All pumps and valves must be correctly supported to prevent unnecessary strain on the pipework.
Nail-in clip and snap-fit with spacer
|Minimum support centres|
|Horizontal pipes||Vertical pipes|
|10mm & 15mm||0.3m||0.5m|