Thermal inertia stoves -also known as thermal mass stoves or rocket stoves- are known especially in colder countries for their high energy efficiency compared to conventional fireplaces.
But more and more they are an alternative in our country thanks to bio-construction and their high efficiency that allows reducing energy consumption and saving costs. But what is the key? Mateu Ortoneda, specialist and author of the manual Construction of masonry stoves, tells us: “The secret is to ensure that the smoke comes out as cold as possible to the surface and that the heat remains in the stove. Herein lies its efficiency ”. And for this, the smoke must be accompanied by a shot with special characteristics.
These stoves make better use of heat because they accumulate it and spread it slowly, even if there is no longer any firewood. If it is also accompanied by materials such as clay mortars, this effect is enhanced by the thermal inertia of the clay itself and comfort is increased due to its ability to regulate the relative humidity of the environment. The image that accompanies this article corresponds to a thermal mass stove built by Mateu Ortoneda in a workshop and in which ecoclay clay mortars are used.
Ortoneda points out that “clay is basic. Mortars regulate the relative humidity of the environment in the exact proportion. Thus they contribute to making homes warmer in winter and colder in summer. A house will always be more pleasant if clay plasters are used ”. And it summarizes in three the keys to bet on thermal inertia stoves:
They dose the heat. The stove stores the heat and doses it. 10 kilos of oak firewood have 4,000 kilocalories, the key is to use it better than conventional stoves. They improve air quality. No positive ions are released into the atmosphere. Radiation heat. The one used in bioconstruction since with less temperature greater comfort is achieved.
Thermal inertia stoves adapt to any decorative style. It must be borne in mind that a ton of material is used for its construction so they can only be installed in homes that support this weight. It is not a recommended system for a weekend home, although there are options that would allow its use. Ortoneda recommends, for example, the thermal shield or the thermal column.