The function of the manifold plumbing system is to distribute hot and cold water to various points of use from a central point. Depending on the property, one or more sets of manifolds will be used.
The principal is to supply domestic hot and cold water to the respective manifolds, and using continuous pipe runs distribute this water to baths, basins, wc cisterns etc.
When connected to an unvented hot water cylinder and cold mains supply, a manifold system will allow adjustments to be made to the flow rate to each appliance for both hot and cold water. It also provides for isolating individual tap outlets to allow maintenance on those taps.
With continuous pipe runs between manifold and tap there is also the benefit of not having to worry about joints under the floor or in other inaccessible places, the complete system can be installed and pressure tested whilst other trades are working. Final fitting of basins, cisterns etc can be carried out after decoration of the property.
The pipe used to distribute water from the manifolds to the appliances is normally 16/2 composite pipe, this material is also known as multi-layer pipe and consists of an inner Pe-x core, aluminium core and an outer Pe-x Layer. The aluminium component is laser butt welded and all layers are bonded together with adhesive. The end result is a very strong material that is flexible enough to be pulled through areas that are normally inaccessible to copper pipe, and yet rigid enough to be neatly clipped in place and not sag the way plastic pipes will.

Connections to the manifolds and the wall boxes serving the appliances is by compression fittings, these consist of M24 nut, compression ring and pipe insert. The insert has 'O' rings on the shank inserted inside the pipe, and an 'O' ring on the flange that inserts into the fitting.
It is important that the pipe is cut square with a roll cutter and the inner Pe-x core is chamfered to allow the 'O' rings to slide easily into the pipe, failure to do this will result in a leaking joint.
16/2 composite pipe is available pre-sleeved, pre- insulated or bare. Bare pipe is in either 200m or 100m coils, sleeved and insulated pipe is in 50m coils. Here...
Calculating the requirements for a building is a simple task and not to different from a conventional system.
Using the building floor plans first determine manifold(s) positions.
Decide which outlets will be allocated to manifolds and count number of hot and cold outlets, this will determine the respective manifold sizes (number of outlets) you will find that the cold manifold will invariably have more outlets than the hot.
Hot and cold distribution manifolds are sold separately and require brackets.
Total hot and cold outlets will determine the number of wall boxes required.
Pipe runs can then be calculated.
See example plans below.
Composite pipe is available in sizes from 16 outside diameter to 63 outside diameter, with a full range of press fittings, press tools and jaws.