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Under floor heating provides you with the design and specifications of the installation process.

Our Engineering Team will specify:

  • Heat Output
  • Amount of pipe
  • Heat Source, i.e. solar, gas, electric, heat pump
  • Individual circuit length
  • Pipe route and layout
  • Manifold specifications
  • Instructions for builders and electricians

Under floor heating will also provide an engineered technical Auto Cad drawing with specification and design of your system.

1) Design Process for Underfloor Heating
2) Define temperature and operating time zones
3) Thermal insulation and basix requirements in NSW
4) Typical performance data
5) Position manifolds and Heat source

1) Design Process for Underfloor Heating

Design Process

2)Define temperature and operating time zones

Operating Time Zones

UFH provides same comfort at lower temperatures due to radiant transfer

Use table below as guide keeping in mind that higher temperatures increase heat losses unless more insulation is used

Without additional insulation, a 1°c increase can raise fuel costs by as much as 15%

Operating Time Zones

operating time zone defines an area in which all floors are heated at the same time

Floors expand when heated and contract when cooled down
=> Expansion joints are required between operating time zones

Use the table as a guide for expansion joint requirements

Operating Time Zones

3)Thermal insulation and basix requirements in NSW

BASIX requires in-slab heating systems to have perimeter and sometimes full slab insulation for ground floors.

Required total R values of construction
Operating Time Zones


  • Minimizes downward heat losses
  • Helps increasing response times


  • Use Tracker sheet System=>Two stage concrete/ screed pour
  • Install thermal insulation underneath slab before pouring or in case of suspended slabs fit after pour

Thermal insulation comes in different densites and R-ratings.
Make sure the insulation is strong enough for your floor application and has a sufficient R-ratings! Typical insulation grade for housing would bd:

  • Medium density with minimum compressive strength of 70kpa and
  • R rating of more than 1.0

4)Typical performance data

Achievable outputs for Different Applications

Operating Time Zones

5)Position manifolds and Heat source

Pipe runs of more than 100m can generate high pressure losses !
=> Keep max pressure below 30 kPa for a typical pump

=>place heat source as close as possible to manifolds to reduce potential heat losses and increase reponse time
=>position manifolds as centrally as possible to the area they serve to minize flow & retun tails to UFH loops
=>For large areas allow for serveral smaller manifolds rather than one big manifold and connect them with ring main ( this also helps prevent complicated pipe runs and assists in keeping the UFH loops at roughly identical lengths and hence hydraulically similar )
=>Manifolds can be placed

  • into surgace mounted or recessed wall cabinets
  • into recessed wall or floor cavities
  • underneath floors ( if access is ensured at all times)