What you need to do when Insulating your floor.


Would you like if in the warm, warm summers, every time you put your feet down on the floor, a whole rush of heat burnt the soles of your feet? Of course, you wouldn't. But isn't that what you experience every summer? As if hell broke loose underneath your floors?

Or in the cold, cold winters, when you have to force yourself out of the warm and cozy blankets and feel the icy chill going all the way up your spine when you are barefoot, looking for your shoes.

If this has been the story of your life for as long as you've known it right? Then it's time you took some action about that cold floor and the cold feet you get every time you thought about cold floors. It's time you got yourself some floor insulation, my friend.

Now, don't let that get you into another train of thoughts, worrying about all the what’s and how’s because we are here to help you with that!

Floor insulation is an integral part of home insulation because your floors are one of the most important and major ways your house will lose and gain heat, accounting for almost 10% of total heat loss from an average home. Other than keeping the temperature optimized, getting house insulation can cut your energy bills drastically.

Basically, there are three types of floors:  

Suspended Floors

Older houses have suspended timber floors and they are likely to lose more heat. For such a type, floor insulation can be in one of the two ways:

  1. Access from Underneath:
If you can easily access the underneath of your floorboards, then you can simply insert rigid insulating board between the joists and use battens to hold them in place. Make sure you cut the insulating board to the exact width of the joists. In a lot of cases fiberglass is also used in this application if access is good via the crawlspace.
  1. No Access to the Underneath

Unfortunately, if there is no access to the underneath of the suspended floor then you might find the job a bit more difficult because the floorboards need to be removed prior to insulating. In this situation wool insulation is used as a preferred option. However again rigid board insulation can be used here also but it will add to an already costly job as this type of insulation is more expensive but will give you better R-Value results.

Insulating Solid Floors

Many homes are built with solid floors, most of which are made from concrete. These, you'll have less of a problem insulating.

Insulating concrete floors cannot be done with the wool used for wooden floors, as this is soft and would compress as people walked across it. Instead, sheets of say Dow XPS Blue Board or Polyiso like Rmax or Hunter insulating board or such as Pactiv XPS 1”, 2” or 3” insulating board. XPS and Polyiso insulation is easy to cut and drill holes in, but has high compression resistance; it also has excellent insulating properties.

Also, it is not necessary to insulate floors on the second or third floor if the rooms below are heated.  

Modern Houses

Modern houses usually already have slabs of polystyrene insulation or XPS insulation incorporated a few inches below the concrete floor surface. And therefore, might not require floor insulation. So, you're good to go! If you wish to upgrade this insulation to a higher R-Value insulation with Poyiso insulation then the concrete would need to be taken up which is very costly.

Benefits of Getting Insulation:

  • It will save you some money on your energy bills.
  • Since the insulation will slow the movement of heat through the floor, the home will feel more comfortable and warmer in the winter, but cooler in the summer months.
  • You can reduce your carbon footprint by about 240 kg per year by installing floor insulation and almost 100 kg if you fill the gaps between floor and skirting boards.


If you are wishing to install the floor insulation as a DIY project, you will need to move furnishings and potentially remove carpets and floorboards.

Additional costs may add up, if once you remove the floorboards, you discover that some are rotten; therefore the overall insulation costs may be higher than previously predicted.

Where to go:

Owen's Corning

Owens Corning is a global company that develops and produces insulation, roofing, and fiberglass composites.

They offer products that are made especially to suit the particular requirements of the areas you are trying to target. Be it floor insulation, crawlspace insulation, roof insulation or wall insulation, they have exactly what you need!

Johns Manville

Being one of the oldest in the game, Johns Manville has mastered the art of insulation, especially home insulation, over the years. Their products offer you superior quality as well as safety to help improve the energy efficiency and comfort of your home. Regardless of whether you start with attic insulation, crawl space insulation or move on to wall insulation, Johns Manville has insulation choices to match your needs and your budget.

Hope this little guide helps you get your floors they way you want them!