The right side of the wall behind this heater is painted with a low-e wall paint, which reflects part of the heat back into the room before it is lost through the wall. So in the winter a low-e wall paint will decrease energy consumption and it increases the thermal comfort. (www.sova-online.de) or direct link www.thermalin.de

In the summer the heat is coming through the roof and the walls from the outside. Then the low-e wall paint will block part of the heat and not release it into the room. Just like a polished silver teapot will not radiate as much heat as a ceramic teapot does.

This technology works like the low-e windows or a thermos flask, only here the mechanism is integrated into a paint.

Brick wall and insulated wall segments have been painted with a standard paint and a colour matched low emissive paint. Temperatures and energy flows of the walls segments have been measured.

The field tests have shown significant energy savings for the non- insulated brick wall system. On the insulated wall segments the energy saving effect was lower due to the high degree of Styrofoam insulation. But the surface painted with the low-emissive coating was not as often under the dew point temperatures as the surface with the standard paint. This prevents cracks in the surface and the growth of algae.

Especially in moist climates newly insulated facades will appear ugly after a short time due to the growth of algae. The photo on the left shows that there is no growth of algae where the fasteners of the insulation build thermal bridges through the Styrofoam. The thermal image on the right shows that the surface around the fasteners is only very little warmer than the rest of the surface. A low emissive exterior wall paint would prevent the growth of algae as it keeps the surface warmer.

Full paper on low emissive coatings in “High Temperatures, High Pressures” under www.hthpweb.com