A simple concept for solar heating is the use of cladding material on south-, west- or east-facing walls. Small gaps enable air to flow in from outside. In the daytime, air passes across the solar panels as well as along their inner surfaces, absorbing the sun's rays to warm the air, causing it to rise. This hot air is drawn into the ventilation system of the building, reducing the load on the heating system. On hot days, such systems can heat air by as much as 30-50°F (17-28°C), depending on the rate of flow.

Snow, on the other hand, can reflect as much as 70% of solar radiation directly into the wall to enhance system performance. This works even on cloudy days, when diffused light can provide as much as 25% of the total radiation of a bright, sunny day.

Such systems may even keep the building cool during summer as the cladding also provides shade for the inner wall; any hot air gathered at the unit's top flows away, out of the gaps, cooling the wall's surface compared to direct exposure to sunlight. Both electrically- and manually-controlled dampers encourage external air to enter the building and maintain air quality.

These dampers switch to provide pre-heated air during the winter. For a solar heating system to be economical, many factors come into play: how old your home is, your heating requirements and the efficiency of the solar thermal system. If a home is thermally leaky, an installed solar system will only provide a small percentage of the home's total heat demand whereas a home that is energy-efficient will enjoy higher returns with the same system. Compare your home's heat loss with the solar thermal unit's heat production to determine the amount of purchased energy (such as gas or oil) which your system can offset. The calculation is complex and should be handled by professional contractors.