Underfloor heating has always been considered the more luxurious form of heating, only because the upfront cost of installation is a lot higher than other systems used to heat your home. It means hard floor surfaces are warm to the touch and the system is completely silent, there is no warm air being blown around your home. The system does not take up any wall space and is completely hidden from view. 

Underfloor systems can run at much lower temperatures than radiator systems,  which increases the efficiency of the boilers and heat pumps used to supply the heat. 

What is underfloor heating?

Underfloor heating is a hydronic heating system that uses a gas boiler or hot water heat pump to produce a supply of warm water. The warm water is circulated through your home via plastic pipes installed within the concrete slab. The pipes within the slab conduct warmth to the surface, which pushes the heat energy to the room above. This system gives even heat to your entire home and is completely safe around children. 

Installation options

An underfloor central heating system is very difficult to retrofit to an existing home as the hot water pipes are embedded within the concrete slab. However, these systems are suited to new build homes. It is very important to plan the underfloor heating well in advance as it is fitted in the slab very early on. 

Underfloor options

There are a few different options when it comes to underfloor heating. The different manufacturers use slightly different technology to achieve the central heating of you home. 

  1. In-slab

This is the most common warm water underfloor heating system in New Zealand. This is mainly because it is the most cost effective to install in a standard home with a concrete floor slab, but it will require special considerations from the architect and builder. A typical Kiwi Inslab system will provide heating to the designated rooms in eight hours and is generally left on low continuously. 

  1. European screed underfloor heating

This is usually around 50mm thick and has reduced thermal mass when compared to in-slab. This is completely insulated from the rest of the building and outside, which means lower heat losses, higher efficiency and faster response to controls.

  1. Multitubo micro-screed

This is a much thinner system using smaller pipes laid into a special moulded floor plate. A screed is spread over the pipes, with the flooring laid over the top. Due to its low weight and height, this method is more suitable for installing over existing timber floors as well as concrete floors. 

  1. Metal plate timber floor system

Alloy plates to spread heat are laid under floor boards or timber panel floors. The pipes are clipped into the plates which conduct the heat away from the pipes. This can be used to retrofit an existing home if the existing floor is strong enough and the raised floor level is acceptable. 

Installation costs

Installation costs may be less than you expect. This will also vary depending on the type of underfloor heating you’ve picked for your home. Some options cost a lot more than other to install, but may have lower running costs in the long run. 

It is important to consider the space that needs to be heated, not the floor size of your home. Most people would not insulate their garage. A house smaller than 100sqm would see a higher installation cost per square metre; while a home bigger than 250sqm would have lower installation costs. 

The type fuel source you use may also impact the installation costs and should be factored in when making your decision.

Running costs

Running costs can vary depending on the source of heat:

  • Natural gas has an estimated monthly running cost of $285 per month
  • LPG has an estimated running cost of $575 per month
  • Diesel has an estimated running cots of $410 per month
  • Firewood has an estimated running cost of $250  per month
  • Air to water heat pump has an estimated running cost of $285 per month 

Things to consider before installing Underfloor Heating

The location of your home may determine which system you use and how much heating is required. Houses in colder parts of New Zealand require more heating. Natural gas is not available in the South Island. 

The energy source available to you will impact installation and running costs. While there are many different fuel source available to provide the heat, they all have different running costs, some cheaper than others. 

In most cases, investing in an efficient system will save you money on running costs in the long run. Installing a cheaper system may save on installation costs, but you may end up spending more on running costs in the long run. 

The way your home has been designed also impacts you household heating requirements. The heat loss of a home in any given location is affected by insulation, amount of glazing, size of windows, lack of curtains, height of ceiling and the complexity of the build. 

Your lifestyle will also have an impact on how much you spend on heating your home. The amount of energy used for heating is highly dependent on temperature preference and operating hours. 

You can also install a split system, where you have a mix of underfloor heating and radiators

It’s very important to make a decision and involve your heating specialists early on in your build. The underfloor heating will be some the first things done during the build and need to be right from the start. Contact us today for a consultation about your options for underfloor heating and installation costs. 


Leave a Reply

Your email address will not be published. Required fields are marked *