Foreign manufacturers tempt UK designers with their beautiful products but when it comes to installing them, the buyer should definitely beware!

When specifying beautiful high-end bathroom products from Europe and beyond for UK projects, designers may be tempted to stick what they know, rather than risk possible differences with plumbing and piping standards. We asked a bathroom company and designer to get the low-down on how to mix the continental product from the client’s wish list with the good old British plumbing system.

‘The first situation where this can be a problem is with the water supply to pans, basins and WC cistern inlets,’ says David Hughes, technical services manager, at top bathroom designer and distributor CP Hart, ‘where the terminations on the connecting British Standard Pipe (BPS) end in a½”male thread and the European inlets have a 3/8” BSP male thread.’

To remedy this, Hughes says, a plumber can use a½or 3/8 brush or swivel nut that will make up the size difference. Other problems can arise with waste /overflow systems where a European bath includes a trap, or where there is any combination waste/filler. ‘Say you are installing a high-end, German Hoesch bath, the last section of the bath trap can often be unscrewed to reveal a 1.5” BSP male thread,’ is Hughes’ tip, ‘use a Compression to Female 1.5” plastic coupling, and you’re back onto UK waste pipe. A McAlpine adaptor can also work.’

Lara Francis, former head designer at Flow bathroom design, now has her own design practice and offers a specialist bathroom and wet room consultancy service. She says her most common issue is with the difference between British and European water pressure, with European being much higher.

‘British taps are tested to British Standard (BP) whereas European fittings are tested to European Notification (EN) to what is called 3 bar pressure. So when using European products in British systems, and the client wants to increase the house’s water pressure, there are a couple of options. They can either have a shower pump fitted to pump the water at a higher pressure or they can have the cold water feed connected directly to the mains and have a combination boiler or unvented cylinder fitted to supply hot water at high pressure.”

Francis often specifies European brands, like Dornbracht, Vola and Hansgrohe, and as a result is familiar with the process. ‘I have worked onmany projects where the client wanted fittings that required 3 bar pressure such as large overhead showers, and so have overseen the upgrading of many a British system!’

In recent years many traditional British tap companies, such as Barber Wilson and Samuel Heath have also started manufacturing their taps to work with either low or high pressure as householders are opting to have combination boilers and unvented cylinders fitted to increase their water pressure.

David Hughes also points out a final and perhaps the most comforting point, ‘If it’s all starting too sound far too technical, while all these suggestions are made to our customers, who are mainly designers, they should not be too concerned with the connections and pressure. It is the plumber who should be coming up with the answer. Of course it’s good to arm yourself with the knowledge you may need, but good tradesman can often come up with a solution.’

This article was first published in idFX Magazine.