Our choice of carpet is often predicated on aesthetic value and practicality around the house, but less so on its insulating properties. However, with recent studies demonstrating that between 10-20% of household heat can be lost through floors, maybe it’s time to change that.
Other research conducted over the years, such as this analysis by UCL and Sheffield University, reveals the power of ground-floor insulation. Something as simple as adding insulation to suspended timber ground floors can reduce heat loss by up to 95%! With all of this mounting evidence, flooring experts have urged homeowners to step up their flooring options before the winter kicks in… which is exactly why we’ve crafted this under carpet insulation guide.
Read on to learn about the most cost-effective flooring options (spoilers, it’s carpet) and why decent insulation under your carpet could shave off a significant amount of your monthly energy bill. And, of course, keep your home looking and feeling cosy all year round.
What exactly is under carpet insulation?
Before we share our top tips for insulating your carpets to ensure your room temperatures remain nice and toasty, let’s lay some of the groundwork (pun unintended).
So what exactly is under carpet insulation? Well, in a single sentence: under carpet insulation refers to the materials laid under a carpet to maintain a stable, regular temperature in a room. When placed correctly under the flooring it will absorb shocks in the floor as well as heat from the warmth of the air inside the room.
Often it will be manufactured from recycled materials such as sponge and foam and may be topped off with an additional layer of insulation above to provide extra protection against the cold. As a result, you get a room that stays warm during the colder months and cool when it’s hot outdoors.
What about thermal insulation underlay?
It’s important to distinguish that under carpet insulation and thermal insulation underlay are not synonymous concepts.
Thermal insulation underlay represents just one specific category within the broader umbrella of under carpet insulation. It’s worth remembering that any material placed beneath a carpet, including carpeting placed over existing flooring, can be considered a form of under carpet insulation as long as it serves the primary purpose of enhancing insulation.
Thermal insulation underlay, also known as underlay or underlayment, is a material that is installed beneath flooring, particularly carpets, to provide additional insulation and improve the energy efficiency of a space by enhancing the thermal insulation properties of the floor. This helps to retain heat and reduce heat loss. In fact, it’s been found that installing carpet underlay can reduce energy costs as much as 15%.
What kind of materials are used for floor insulation?
We mentioned previously that recycled foam and sponge are common insulation materials that go under carpets, but what other materials are available? It turns out there are quite a few, and you can divide them into two categories.
Synthetic insulation
You can find synthetic insulation in both pads and roll-out sheet form, but you are most likely to encounter it in batts. Insulation batts are one of the most common types of thermal insulation for residential housing and they are essentially comprised of large insulation pieces held firmly together and whose fibres are tightly interwoven.
These products are all relatively cheap, but they come with an environmental cost. However, they are a step up from virgin materials as they are often sourced from recycled materials.
Organic insulation
An alternative to synthetic types of insulation, organic insulation refers to insulating materials that are non-toxic and biodegradable. You’ll be surprised by what sort of materials that can heat-proof your home. From coconut husks to cotton, there are so many options that will retain their form over time. The only downside is that they are more difficult to get a hold of, and therefore more expensive.
Our carpet underlay recommendations
It’s no secret that carpet is an effective source of insulation in and of itself, and you can improve this natural quality by a huge amount by pairing it with the best type of carpet underlay.
Although underlay isn’t technically a type of under carpet insulation as we’ve previously established, it works as a brilliant floor insulation enhancer, so you will want to include both for an extra toasty room. Generally, it all comes down to picking out the right materials.
When selecting your underlay, you will generally have 4 choices:
- PU (polyurethane) underlay
- Rubber (sponge rubber) underlay
- Crumb rubber underlay
- Combination underlay
While you will see variation in the merits of each underlay type – for instance, PU is the prevailing choice in the market due to its widespread availability and competitive pricing – there are a few that excel in their insulating qualities.
Both felt and PU foam offer high thermal insulation properties at affordable rates. Typically produced from recycled foam offcuts, they are more environmentally friendly options compared to virgin materials. Plus, they provide a variety of thickness options, catering to various flooring needs while accommodating different budgets.
An alternative to these two is crumb rubber underlay. Invariably durable and, thus, frequently employed in high-traffic areas, such as pubs, hotels, and offices, its sound and heat insulation is very strong. Do note, however, that it doesn’t provide the same softness underfoot as the previous options.
Understanding carpet underlay tog ratings
Another key concept to under carpet insulation is tog rating. The thermal conductance, alongside other properties such as how effective the underlay is at trapping pockets of air, is converted into a tog value – in other words – a warmth rating. The tog value of underlay can measure up to 3.13 tog, with carpets clocking in at around 1.0-22.2 tog.
Carpet underlay with a tog value of 2.5 or higher is a brilliant choice for homeowners hoping to improve the underfloor insulation around the house.
3 steps to improve under carpet insulation in your home
So with all that information in mind, here are three steps to improve the efficiency of your carpet insulation.
1. Implement underfloor insulation
If you’re going to add a new carpet, you want to upgrade the underfloor insulation. For suspended timber floors, insulate between the joists using solid insulation boards or mineral wool placed inside the cavity and secured with netting. This may require lifting the floorboards. If the floor is above an unheated basement or cellar, ensure fire resistance by adding plasterboard to the ceiling.
In the case of solid concrete subfloors, opt for rigid insulation foam. This can be placed below the concrete when pouring fresh concrete or laid above the existing concrete surface, with chipboard covering it. If this sounds complicated, no worries. An experienced flooring fitter can help you achieve a high-quality finish no problem.
2. Add a high-quality underlay
We don’t need to go into too much detail here as we’ve already covered it: but if you want to enhance the insulating qualities of your carpet, go for a hard-wearing underlay with a good tog rating.
3. Seal any gaps
Finally, before you lay down your new carpet, make sure that there are no gaps or openings in the insulation layer. Use sealants or additional insulation materials to close any holes.
Bonus methods for improving your carpet’s energy efficiency
1. Upgrade the material or tog of your carpet
You might have a good underlay, but if the quality of the carpet itself is poor, what’s the point? Ensure that you’ve shopped around for your new carpet, so you get the best deal for your budget.
2. Consider adding extra layers
Another, much quicker, fix is to add extra layers. This could be in the form of additional layers of insulation or you might want to add a warm rug or two.
3. Opt for a professional installation
The final thing you can do to ensure that your carpet will be well-insulated is to opt for a professional installation. By consulting with an expert, you are sure to get a high-quality service and a finish to be proud of.
Winter-proof your home
It’s clear that under carpet insulation isn’t just a practical consideration; it’s a game-changer for your home’s comfort and energy efficiency. With the potential to significantly reduce heat loss and trim down those soaring energy bills, the decision to invest in an efficient and comfy carpet underlay speaks for itself.
If you’re ready to take the next step and explore the world of under carpet insulation, we invite you to reach out to our experts here at Derwenthorpe Flooring. With more than 40 years’ of experience, we can offer personalised recommendations and fittings that the big retailers just can’t beat.
