Wallrock Thermal Liner

As the Autumn transitions into Winter, there comes a point where despite our best intentions to save energy, we cannot feasibly add yet another layer of clothes; it’s time to turn on the central heating. But how can we ensure the valuable heat energy is retained within our home? This article reviews Wallrock Thermal Liner.

Pre-1930s Homes

In newer homes, thermal efficiency will have been carefully considered from initial design phase, and in England will have been constructed with thermal insulation to achieve the minimum U values outlined within Part L of the Building regulations. However, it is estimated that 40% of us live within homes constructed pre-1930s, before cavity walls became common place and long before the Building Regulations were even dreamed of. There is a wealth of advice available to those dwelling in older properties (see Top Ten page for a holistic range of tips on improving the thermal efficiency of older houses) however today we will look at how applying Wall Rock Thermal Liner to your walls can help improve the energy efficiency of your old home.

Who is Wallrock?

Wallrock (not to be confused with Rock Wool insulation) is a brand created by the UK/German fusion company Erfurt MAV. This family run company has over 75 years of experience in creating wall coverings and were wholly responsible for the wood texture wall covering which was extremely popular in the 1970s.

“her house was very small… with woodchip on the wall…” (Pulp, Let’s All Meet Up in the year 2000.)

Wallrock is one of Erfurt MAV’s more recent innovations, contributing towards the companies’ environmental achievements, including the Blue Angel award for developing environmentally friendly recycled products and ISO 9001 Quality Management certification.

What is Wallrock Thermal Liner?

For many homeowners, the installation of internal insulation (such as Celotex’s Thermal PIR insulation) is not an option, as it is not only expensive but will also decrease the size of the room.  Wallrock’s Thermal Liner on the other hand is a lining paper, similar in appearance to a roll of wallpaper, which professes to “significantly reduce heat loss and room warm up times” as well as “combats condensation and mold formulation for a healthier home”. An additional bonus of Wallrock thermal Liner is that it has been accredited as suitable for allergy sufferers, containing no PVC or fiberglass.

The Thermal Liner is available in two thicknesses, 3mm and 6mm. My research found that the Energy Saving Trust has listed Wallrock thermal Liner because of its thermal efficiency and energy saving properties. According to its BBA certificate, the 3mm thermal liner alone has a standalone U value of 12.19 W/m2K and achieves a 15% energy saving when applied to an external solid brick wall. The liner works by slowing down the rate at which a cold walls absorb heat energy, allowing rooms to warm up considerably faster, in some cases more than halving warm up times, creating a comfortable room environment with less energy. This effect is valuable in any home with solid walls and even those with external or cavity insulation – especially where the heating is regularly turned on and off. Once the room is warmed up and comfortable, Wallrock Thermal Liner goes on working, producing steady energy savings. Furthermore, Wallrock Thermal Liner has excellent capability to cover and reinforce poor plaster and other surfaces such as plasterboard, blockwork and wood panelling.

Wallrock Thermal Liner also helps reduce condensation problems and, in many cases, eliminates them – as more room warmth is retained at the wall surface at an earlier stage in the warm up phase there is far less opportunity for condensation to form on a cold wall and consequently a reduced risk of unhealthy mould growth. The manufacturers claim that the surface of Wallrock Thermal Liner is longlasting, durable and suitable for painting directly. For these reasons I decided to give it a go in both of my spare rooms which have north facing external walls…

The verdict

This product is not for the faint hearted DIYer, as it requires extreme care and precision to avoid creasing the lining paper – I discovered that once creased it cannot be flattened out, and the surface will forever have a lightning strike appearance. You have been warned! Also, as the liner is so thick, it requires an extremely generous application of the Wallrock Thermal Liner Adhesive to stay in place. The liner is difficult to cut and is especially tricky to detail around window reveals (the surface is to be scored, but only on the surface so as not to cut through the underlying fleece.) Investment of time and money is necessary to get the job done, but I can confirm it is absolutely worth it!

The Thermal Liner has made both of these rooms feel substantially warmer whilst also providing an excellent finish for my paint. Furthermore, the liner also has sound insulating properties, improving the privacy of these rooms for their users.

For more information, please visit: https://www.erfurtmav.com/erfurt-mav-wallpaper-products/wallrock/wallrock-thermal-liner

Or watch their video here:

NOTE: The manufacturer highlights that this product is suitable as a localised ‘problem solver’ for cold external walls and is not recommended for use in fire escape routes inside your home unless the surface is further treated with a fire retardant covering. This product is class E fire rated and should not be used for projects such as new builds and extensions where Building regulations are applicable. However, Wallrock also manufacture Fireliner which achieves Class 0 surface spread of flame (tested to BS 476) which can be applied directly over the Thermal Liner.