How to Achieve 0.18 U-Value in Solid Floors

It is common to aim for a U-value of 0.18 when insulating both domestic and non-domestic floors. If you’re going through the process of insulating a concrete floor to meet building regulations, you may be required to reach a U-value of 0.18.

To achieve this low U-value a common approach is by using a generous layer of Rigid PIR Insulation. However, using a thick layer of PIR insulation is quite costly and may result in a loss of valuable head height. We will show you how to achieve a 0.18 U-value in Solid Floors.

U-Value’s Explained

A U-value is the measurement of heat loss. They can measure the energy efficiency of an area within your home such as roofs, floors, walls, and windows. As the heat escaping from an area reduces the U-value decreases. When constructing an extension or renovating an existing concrete floor, it is crucial to ensure that the floor meets the required U-value.

A U-value is calculated by the total thermal resistance of all the layers that make the structure. For example in a roof elements such as tiles, membranes, air gaps, and timber can influence the U-value either positively or negatively.

Meet a 0.18 U-Value in Solid Floors using YBS SuperQuilt

Building Regulation U-value 2024

In June 2022 the current U-value targets were set, these can be viewed in the table below. For more information on Part L follow the link to the UK Government website – See Data Source.

U-value requirements for existing dwellings – 2022 onwards

Application Current U-value
Roof (Pitched & Flat Roof) 0.15
Wall 0.18
Floor 0.18

Here at Multifoil Insulation, we highly recommend using YBS SuperQuilt to insulate your solid and concrete floors. SuperQuillt is a 40mm thick multifoil insulation that compresses down to 7mm at its thinnest point. SuperQuilt is also certified for both walls and roofs not just floors. It’s made from 19 layers of true aluminium foil, recycled wadding, and PE foam.

YBS superQuilt is fully agremont certified by BDA and it also equates to around 100mm of Rigid Insulation in floors. SuperQuilt is manufactured within the UK around 30 minutes away from our distribution centre. It’s manufactured from 83% recycled materials which are free from any itchy floating fibers and it also has a Class E surface spread of flame classification.

How to Install YBS superQuilt to Achieve a 0.18 U-value

Below is our recommended build-up to achieve a 0.18 U-value;

  • Solid Concrete Floor
  • 1st Layer SuperQuilt laid flat on the floor
  • 50mm Battens with narrow centres
  • 2nd Layer SuperQuilt stapled taut over battens
  • 22mm Chipboard Finish
  • U-value achieved = 0.18 or lower

This detail will take up a total depth of approximately 86mm.

Are you Going Through Building Control?

Building Control will likely want to see documentation. If they do, we can help you out! Please use our Request a U-value form. Please mention the build-up of your floor as well as the m2 coverage.  We will then email a bespoke calculation and quote within 24 hours. (Monday – Friday)


We offer FREE next-day delivery on all orders over £100 + VAT to the UK Mainland.

YBS Superquilt can be purchased as loose rolls and is also available as a Trade Pallet Deal to save on cost.

Follow the links below to order online, you can also call us for more information.

YBS SuperQuilt Loose Rolls – Click Here

YBS SuperQuilt Trade Pallet Deal – Click Here


All build-ups and suggestions are provided in good faith. We recommend having these details double-checked by building control before proceeding. The U-value table is a guide, and your desired target U-value is to be advised by your building inspector. Please check the calculations for correct air gaps and battens, battens may be required to be installed perpendicular to how they are supplied in the image. 2D images are not to scale and are for illustrational purposes only. Multifoils-Direct cannot be held responsible for any losses financially as well as physically from the advice provided on this webpage.