Insulating a floor: warm feet and a lower energy bill

Cold feet in the living room, even though the heating is on? Then there is a good chance heat is escaping through the floor. Especially in homes built before the 1980s, the ground floor is often barely insulated, if at all. Insulating a floor is relatively straightforward, often pays for itself and feels more comfortable straight away. In this article you will read which methods exist, when to work via the crawl space and when from above, and what you can do about VAT and grants.

Why is it worth insulating your floor?

An uninsulated floor above a crawl space is cold in winter. You feel it in your feet and in draughts along the skirting boards. After insulation the floor stays warmer, so the room feels comfortable at a lower temperature.

You also see it in your gas consumption. Exactly how much depends on the home and how you heat it. Floor insulation is, however, one of the measures with a good balance between cost and effect. If your walls are not insulated yet either, also have a look at insulating interior walls.

There is another advantage. An insulated floor makes it easier to switch later to low-temperature heating, such as underfloor heating or a heat pump. These work best in a well insulated house. That is why floor insulation is often a logical first step.

Insulating a floor via the crawl space

If there is a crawl space of sufficient height, you usually insulate from below. Then nothing needs to be opened up inside the house. The best known methods are insulation boards against the underside of the floor, sprayed foam and a layer of insulation chips or shells on the bottom of the crawl space.

Boards and foam insulate the floor itself. Ground insulation keeps out damp and cold from below and works best in combination with a dry crawl space. Which method suits depends on the height, the humidity and the type of floor. A concrete floor sometimes needs a different approach from a timber floor.

A ground membrane is a common addition. It keeps moisture from the soil out and makes the crawl space drier, which benefits the insulation and the timber parts.

• Crawl space high enough to work in
• Crawl space dry, without standing water
• Crawl space ventilation keeps working
• Check the pipes in the crawl space at the same time

No crawl space? Insulating from above

If your house has no crawl space, or it is too low, the insulation can also go on top of the floor. You then lay insulation boards on the existing floor with a new screed or finish over it. That costs a few centimetres of height. Doors, skirting boards and the bottom stair tread need to be adjusted accordingly.

This is often a logical moment for a bigger job. One of our clients started with just insulating the floor. Underfloor heating, plastered walls, an insulated ceiling, tiles and a moved door followed. In floor renovation and insulation you can read how we approach that.

Roughly what does floor insulation cost?

The price depends heavily on the method, the number of square metres and access. Insulating via the crawl space is usually cheaper than from above, because no finishes in the house need redoing. In our article on the cost of floor insulation you will find indicative amounts per method.

Good to know: the reduced VAT rate of 9% applies to the labour for insulating a home that is more than two years old. For floor insulation there is also the ISDE scheme of the RVO. Read more in ISDE grant for insulation and check the current conditions on rvo.nl.

How we approach it

At Daal Constructions we start by looking. How high is the crawl space, is it dry, and what kind of floor is there? Then we advise the method that fits. Sometimes that is simply fitting boards, sometimes a renewed floor is the better choice.

Shahiro is your fixed point of contact, from the first visit to completion. Feel free to send a WhatsApp message with photos of your crawl space hatch, so we can already make a first assessment. Or request a no-obligation quotation straight away.

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