There are many ways to insulate your home, some more obvious than others. Insulation projects often focus on exterior walls, ceilings, and other parts of the house, and while insulating these areas is certainly important, they aren’t the only way to insulate your existing home.

When looking to insulate your home to make it more comfortable and economical year-round, while also adding value to the property, it pays not to overlook underfloor insulation and the space under your floors.

What is underfloor insulation?

The concept of addressing and managing the flow of heat through the flooring in homes is not new. In fact, the idea can be traced all the way back to Korea circa 5,000 BC and the use of the Ondol system.

Like other forms of insulation, underfloor insulation provides an effective barrier to the flow of heat through suspended timber sub-floors and helps reduce your reliance on heaters in winter and air-conditioners in summer. Such artificial heating and cooling methods add to your electricity bill while contributing to greenhouse gas emissions.

Homeowners may overlook the underside of their floors as an area where heat can enter or exit their homes. So while you may have sufficiently insulated parts of your home, such as the walls and ceilings, you will still be losing significant heat – or gaining significant heat when you least want it – if your suspended timber sub-floor isn’t supported with underfloor insulation. Either way, it is costing you money by increasing your reliance on heating and cooling systems in your home.

flooring installation

Installing underfloor insulation as a DIY project

While an effective insulation strategy for your home, it’s worth noting that many underfloor insulation products are also easy to install. There are a range of different underfloor insulation products on the market, so if you’re considering doing the installing yourself as a DIY project, you’ll find several options that you will be able to install yourself.

Whether retro-fitting under existing floors or as part of a new floor installation, installing underfloor insulation can often be done by the homeowner who enjoys working on DIY jobs around the house. All that’s needed is a few basic tools.

Underfloor insulation products typically come with a complete set of easy-to-follow instructions for DIY installs, while some suppliers also offer installation videos on their websites to help. When doing the install yourself as a DIY project, it pays to look for a supplier who offers underfloor insulation in a range of widths, including the custom sizing if needed. Be sure to ask them any installation questions you may have when purchasing the product.

Five ways that underfloor insulation adds value to your home

Here are five ways that underfloor insulation can add long-term value to your home by simply making it more cost-effective, efficient, and a more comfortable place to live.

socks on timber flooring

Get rid of those drafts

Underfloor insulation helps eliminate drafts in homes that are raised above the ground. If the floor joists are accessible, rigid insulation panels are placed between the floor joists; if they are enclosed, then spray foam insulation can be used. Either way, you will be creating a barrier that will prevent drafts from coming up through your floor.


Prevent heat loss

While it doesn’t make your floor warmer by itself – let’s not confuse underfloor insulation with heated flooring – underfloor insulation will help your house retain heat. Insulation reduces temperature change, meaning less energy is needed to maintain your preferred temperature inside your home.

 Reduce unwanted moisture

Wood floors are particularly vulnerable to moisture. By installing underfloor insulation you will be creating what’s called a ‘vapour barrier’, which prevents moisture from gathering on the underside of your raised wooden floor, which over time may cause the floor to warp or become stained. All underfloor insulation creates a vapour barrier that reduces the risk of moisture to wooden floors, but rigid panel insulation products do it the best.

Protect your pipes

For those living in the colder parts of Australia in homes with piping beneath their wooden floor, underfloor insulation provides an additional level of protection when the water in the pipes reaches freezing temperature. This can cause the pipes to crack, if not completely burst, so underfloor insulation may be the difference between damaged pipes and pipes that remain intact.

Make summers more manageable

Insulation isn’t just for winter. Underfloor insulation also helps to control the temperature inside your house during the warmer months. As science tells us, hot air rises, and the hot air below your raised timber floors will continue to rise and enter your home if you don’t install a barrier to block it…in the form of underfloor insulation.


Trusted for more than 20 years, EXPOL underfloor insulation is easy to install, available in four convenient joist widths (560mm, 470mm, 410mm, 360mm), and a popular option for DIY underfloor insulation projects.