Tog rating is a term, that in the UK we’ve learned to associate with duvets, but we tend not to link it in our minds with flooring. That said, once pointed out, it’s logical enough that the likes of carpeting has a tog rating. What may seem more odd however is that the underlay used in conjunction with wood flooring also has a tog rating.
So what exactly is a Tog Rating?
Tog is the term used to describe the amount of of thermal insulation in a material, or in simpler terms, how warm something will keep you. A concept which was introduced by the Shirley Institute in Manchester in the 1940s the term tog is most commonly used, as already stated, in the rating of duvets. Most people are now familiar with the notion that a 3 – 4.5 tog duvet is intended for summer use, whereas a 12 – 13.5 tog duvet will keep the worst of winter cold at bay. What we’re not so used to however is thinking about the importance of tog ratings in flooring.
The importance of tog ratings in flooring
If you’re planning to re-floor a draughty old house that has huge gaps in its wooden floors, it makes complete sense to consider carefully the tog rating of both your carpet and your underlay, but what if you have under floor heating? Under floor heating has become much more popular in recent years and as such, people are needing to pay more attention to their decision making process when fitting a new floor.
Under floor heating
One of the great things about under floor heating is that it works with the natural movement of heat. Because heat rises, it makes best sense to have the source of heat at the lowest point in your room. Because most radiators are fitted around waist level, the heat that comes from them, it rises to head-height, only to come down again as cooler air. This isn’t the case with under floor heating.
There are essentially two types of under floor heating: water and electric. Water based under floor heating, relies on the passage of warm water through a piping system which is installed under the floor. Connected to a boiler or a solar water heating system, it is generally considered an efficient way of heating your home because it is designed to work well with a lower water temperature than traditional radiators.
The main negatives of water based under floor heating are the amount of piping that’s required; the skill needed for it’s installation and the fact that you need quite a big room to make it cost effective. Another issue is that the pipes require more depth and for these reasons, many people plump for electric.
Electric under floor heating is a series of electric wires that are placed either under, or within your flooring. Quite often, electric under floor heating is fitted in sheets with loose-fit wiring used to accommodate tight or awkward spaces. Recognised as a simpler installation process than water based under floor heating, electric under floor heating is something a competent DIY-er might tackle on their own, albeit asking a qualified electrician to connect the system to the mains. The main downside of electric under floor heating is that it is more expensive to run than water based under floor heating.
Once you’ve decided what sort of under floor heating is best for your project, you then need to firm up your flooring plans. If you’re plumping for carpet, then you’ll need a carpet that allows the heat to pass, otherwise you’ll have wasted your efforts and you’ll continue to waste money. It is generally accepted that a carpet with a tog rating of 1.5 or less should work fine. That said, you need to take into the account the underlay you’ll use with your carpet. In most cases, a lightweight sponge underlay will have a low tog rating of around 0.5 and will be fine, but like all things of this nature, if you’re in any doubt whatsoever, you should take the time to check with your supplier.
When it comes to wood flooring underlay, again you should be looking for an underlay with a tog rating of 0.5 or lower to make sure that the heat can pass successfully. Most wood flooring underlays are marked with their tog rating and also a clear indication as to whether they are suitable for use with under floor heating or not. But once again, it is essential to seek advice if you’re in any doubt whatsoever.
The two options side by side
| Water-Based UFH | Electric UFH | |
|---|---|---|
| How It Works | Circulates warm water through an underfloor piping system connected to a boiler or solar water heating system. | Utilizes a series of electric wires installed under or within the flooring. Often fitted in sheets, with loose-fit wiring used to accommodate tight or awkward spaces. |
| Installation Complexity | Requires skilled installation due to the extensive amount of piping. | Generally simpler to install than water-based systems, making it a potential DIY project (though a qualified electrician should handle connection to the mains). |
| Room Size Suitability | Most cost-effective in larger rooms due to the amount of piping required. | Suitable for all room sizes, including tight or awkward spaces. |
| Running Cost | Generally less expensive to run than electric UFH due to its efficient use of lower water temperatures. | More expensive to run compared to water-based UFH. |
| Flooring Compatibility | Requires consideration of the floor covering’s thermal conductivity. Carpets should have a tog rating of 1.5 or less, and underlay should have a tog rating of 0.5 or lower. | Also requires consideration of the floor covering’s thermal conductivity. Carpets should have a tog rating of 1.5 or less, and underlay should have a tog rating of 0.5 or lower. |
—
FAQ
What is a Tog Rating?
Tog is a term used to describe the amount of thermal insulation in a material, indicating how warm something will keep you. Introduced by the Shirley Institute in Manchester in the 1940s, tog rating is most commonly used in rating duvets, but it is also applicable to flooring and underlay.
Why is Tog Rating important in flooring?
Tog rating in flooring is essential because it determines how much heat the flooring material can retain. If you live in a draughty old house with large gaps in its wooden floors, the tog rating of your carpet and underlay should be carefully considered. It’s even more crucial when dealing with under floor heating systems.
What are the types of under floor heating?
There are two primary types of under floor heating: water-based and electric. Water-based under floor heating relies on warm water passing through a pipe system installed under the floor. On the other hand, electric under floor heating uses a series of electric wires placed under or within your flooring.
What should be the Tog Rating for carpets used with under floor heating?
For carpets used with under floor heating, it’s generally accepted that the tog rating should be 1.5 or less. This ensures that the heat can effectively pass through the carpet. You also need to consider the underlay you’ll use with your carpet; a lightweight sponge underlay with a low tog rating of around 0.5 is often suitable.
What about the Tog Rating for wood flooring underlay?
For wood flooring underlay, the tog rating should be 0.5 or lower to ensure that heat can pass successfully. Most wood flooring underlays are marked with their tog rating and an indication of whether they’re suitable for use with under floor heating.