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Luxury underfloor heating


An efficient renewable heating solution to include boiler back-up


A split 16kW ASHP with boiler back up integrated with UFH

Windsor House is a bespoke luxury property in Virginia Water, Surrey. AH Lyons, the housebuilder behind the project, specialise in high-specification homes with a quality finish, typically building one large property a year. Windsor House is a luxury mansion of approximately 793m2, consisting of 6 en-suite bedrooms, 6 receptions rooms, a triple garage and an outdoor pool.

Windsor House required a highly efficient and reliable renewable heating system. The solution Nu-Heat provided had to include boiler back-up, covering the property’s heat load in the unlikely event that the air source heat pump should fail.

The Nu-Heat solution

We worked with AH Lyons to design a bespoke, efficient heating system that included a single Hitachi split ASHP with UFH. Boiler back-up was also carefully integrated with the ASHP, providing an added benefit should the ASHP ever be out of operation.


Hitachi Yutaki split 16kW ASHP

This split ASHP produces a high heat load from a single unit, avoiding the need for more than one heat pump in larger properties, and is simple to install.

  • Key components and electrical controls built into indoor unit to simplify installation
  • Can be connected to a boiler to cover a higher heat load
  • Compatible with KNX home automation
  • Inverter controlled compressor to closer match the heating demand
  • Split system allows smaller diameter pipework to be installed up to 30m between indoor and outdoor unit

SC14 – screed

This screed floor construction is used frequently in new-build projects. Simple to install, the 14mm UFH tube is simply clipped into standard insulation before the screed is poured.

  • Flexible 14mm tube is easy to install around numerous turns in design
  • Use of multiple coils within zones means the tubing is installed at closer centres, suitable for low temperature heat sources such as an ASHP

Heat output – performance with ASHP

Water temp produced by ASHP Natural stone/tiles 14mm engineered board 2 tog carpet/underlay
35°C flow 29 W/m2 26 W/m2 20 W/m2
40°C flow 45 W/m2 40 W/m2 31 W/m2

SL20 – screed

Also installed in Windsor House, SL20 is another screed solution ideally suited to large open plan areas. This floor construction uses 20mm tube.

  • The longer coil length offers a simplified installation
  • Larger floor areas can be covered with each coil, reducing any clustering of tube at the manifold
  • Good heat outputs, slightly higher than SC14

Heat output – performance with ASHP

Water temp produced by ASHP Tiles with decoupling mat 14mm engineered board 2 tog carpet/underlay
35°C flow 40 W/m2 31 W/m2 26 W/m2
40°C flow 61 W/m2 47 W/m2 39 W/m2

All images © AH Lyons

Call Nu-Heat on 01404 549770 or email info@nu-heat.co.uk to discuss your upcoming projects. You can also view our Underfloor Heating page for more information.

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