Comfort and safety

Knauf Insulation’s essential guide to creating a warm winter home

By Knauf Insulation
October 28, 2021

Feeling the cold? Home full of chilly rooms? Knauf Insulation’s Head of Building Science shares his expertise on how to improve the comfort of your home this winter.

Nights are getting longer, days are getting colder and across the Northern Hemisphere, the appeal of wearing a warm sweater is becoming increasingly irresistible.


Winter is coming.


And for those who are discovering — or have forgotten — how cold their homes can become at this time of the year, Knauf Insulation’s Head of Building Science, Domen Ivanšek, has plenty of advice to help.

“We are all familiar with the challenges of achieving winter comfort — low temperatures in rooms, cold internal surfaces, low thermal comfort, the temperature asymmetry of indoor surfaces when one surface is colder than others and unwanted cold drafts,” he says.

Combine these factors with humidity, bad indoor air quality, condensation on internal surfaces and soaring heating costs and homeowners have a recipe for a particularly expensive, unhappy and unhealthy winter.

The solution is to keep internal surfaces warm, provide additional heat and fresh air in indoor spaces and limit heat losses as much as possible, says Domen, a civil engineer and specialist in building  physics who works daily with architects, installers and customers.

Domen Ivansek

Importance of preparation

“So where do you start? With good preparation, a big picture in mind, a timeline to resolve all issues and enough time to distribute different tasks and have them carried out thoroughly,” he says.

“I would recommend involving building energy and insulation experts in the initial stages of any renovation, because they can explain potential challenges and help to avoid problems in advance.”

As winter external temperatures are lower than those indoors, the whole building envelope needs to have good thermal insulation — and good glazing if possible — to prevent heat leaking through walls, roofs and floors, Domen says.

In an uninsulated house up to 60% of heat can be lost through external walls, doors and windows and up to 30% lost through roofs. Also never underestimate uninsulated floors which can have a significant impact on thermal comfort.


Follow a clear renovation sequence

When improving the thermal characteristics of a building, Domen recommends following a clear sequence of measures starting with the airtight installation of modern windows and doors followed by the professional installation of thermal insulation on external walls and around windows.  

“Good thermal insulation on the external side of walls, supported by heavier building material layers on the inside will achieve the most stable indoor temperatures,” he says.

“These measures should be followed by the installation of thermal insulation in the roof or loft and then insulation in the ground floor or basement ceiling if applicable.”

As a general rule, external wall insulation should be thicker than basement ceiling insulation and roof or loft insulation thicker than that of the walls, he says.


Make the building envelope air-tight

Domen also warns of the importance of ensuring an air-tight envelope to eliminate the uncontrolled leaking of heat and vapour using dedicated membranes and sealants. These will also provide protection against condensation in building elements.

Once the building envelope is correctly insulated — including balconies, overhangs and the junction points of different building and installation elements — it is time to consider active measures such as replacing old heating systems with a more suitable and efficient systems and ensuring effective controlled ventilation, preferably with heat recuperation.

“Any improvements to the building envelope will provide benefits,” says Domen. “But ultimately a thorough, deep energy efficient renovation will be a worthwhile investment for many years to come in terms of energy savings, thermal comfort and a healthy home.”


How can Knauf Insulation help?

Knauf Insulation offers a wide range of expertise as well as high quality solutions that can be installed externally and internally to improve the thermal comfort of any building type.

We offer products that provide outstanding thermal performance ranging from Rock Mineral Wool and Glass Mineral Wool to Wood Wool and Blowing Wool in addition to our Urbanscape Green Roof and Wall solutions.

Our solutions are also fire safe, provide exceptional acoustic performance and have great eco-credentials. For example, our Glass Mineral Wool with ECOSETechnology® is composed of up to 80% recycled glass and contains no added formaldehyde, artificial dyes or acrylics.

Our solutions can be tailormade to meet any thermal comfort requirements and we have the technical expertise available to find solutions to any building challenge.

Furthermore, we offer accessories such as vapour control layers and weather membranes in addition to tapes and sealants to ensure the highest possible standards of installation.


Here is a selection of some of our solutions:


Our Glass Mineral Wool solutions for pitched roofs can be laid between joists as well as friction-fitted insulation installed between rafters and even below to ensure a high thickness of insulation.

Our Rock Mineral Wool insulation solutions for flat roofs offer excellent thermal performance as well as contribute to fire safety thanks to an A1 reaction to fire.

Our Mineral Wool facades can be easily fixed to building exteriors — providing an advantage of keeping heat in the mass of the walls — while our standard ETICS products are designed for render coating and included in the system of main ETICS system providers.

Our lightweight ventilated façade systems combined with our Mineral Wool are popular because they are easy and quick to install, and provide a range of aesthetic options for architects and specifiers from wood and PVC claddings to panels or boards of different materials.

Our Urbanscape Green Roof solutions can be customised to meet any thermal requirements and are great for biodiversity and absorbing CO2 and air pollution as well as reducing heat island effect when urban areas are hotter than outlying areas.

Our SUPAFIL Blowing Wool is ideal for new buildings, renovation and for prefabricated buildings with a range of applications for lofts (attics), cavity walls and timber frames.

Our Heraklith Wood Wool insulation panels — and wood wool finishing panels for walls and ceilings — not only offer a range of different mounting methods but also provide excellent thermal performance due to their wood wool fibre structure and an exciting range of coloured finishes which makes them an attractive addition to any commercial or non-commercial interior.

Our Homeseal solutions ensure interior comfort by locking in the internal heat of your building while allowing it to breathe. Our Homeseal accessories are important elements to be installed as they protect insulation from condensation risk and avoid air leaks that lead to a loss of energy.