Wood reacts to moisture, water, and heat and continues to „expand and contract“ throughout its lifetime. Simple wooden beams and boards can warp and twist over time, thereby compromising the building’s airtightness. User behavior also plays an important role in this regard.
While homeowners may be aware of how important airtightness is to the overall structure in the early years, that awareness often fades over time.
If, after 15 years, a hole is drilled for an electrical outlet and the airtight layer is compromised, condensation can form unnoticed behind the panels in the insulation layer. This can cause serious damage not only to the structure but also to indoor air quality. Such leaks are often not noticed until the insulation and structure are damp and mold spores may already be detectable in the indoor air.
Wood-based materials are hygroscopic, which means they absorb moisture. As a result, they are generally more susceptible to the effects of water and weather.
Facades must be planned very carefully and constructed by professionals.
Leaks around window sills, joints, or other structural components can quickly cause permanent damage to a wooden structure.
The weight of a solid building limits the extent to which it can be prefabricated and transported. Solid houses are usually built on-site, either by laying brick or pouring concrete. The construction phase lasts several months and is inevitably exposed to the elements, which is why the drying phase after the roof is installed can also take several months.
At the very latest, however, by the time the electrician connects the doorbell, the house will have only a minimal amount of residual moisture left, which will disappear completely after the first heating season.
Solid, heavy materials such as stone, metal, glass, concrete, or brick have a high specific density and are therefore highly thermally conductive. This means they conduct heat very well, which is undesirable in home construction, since the goal is to minimize the loss of climate-damaging and expensive energy. Nevertheless, additional insulation measures ensure maximum comfort.
Over the past few decades, the stone industry has developed porous wall blocks that reduce their specific weight through air pockets and chambers and achieve better thermal insulation values.
Today, the classic hollow brick not only has many chambers that are directly visible, but beads (e.g., EPS) are also mixed into the clay-rich loam; these burn off during the firing process, thereby creating additional air pockets.
However, this porosity also makes the wall material softer, which makes it more difficult to anchor heavy objects in the masonry.
Many types of masonry blocks, such as aerated concrete, pumice, or expanded clay blocks, contain as many air pockets as possible. This improves insulation performance but comes at the expense of strength and structural sound insulation.
To prevent increased heat loss in solid wall materials, an additional layer of thermal insulation is installed. This measure must be carefully planned and implemented consistently to prevent thermal bridges.
Such thermal bridges can lead to cold spots in the house where indoor air condenses—which promotes mold growth.
An important advantage of solid-construction buildings is that the mass of the walls and floors stores heat, thereby ensuring a more stable indoor climate. Interior structural elements, in particular, serve this function.
The exterior components, on the other hand, act as a barrier between warm indoor air and cold outdoor air. Even with the best thermal insulation, heat flows along the temperature gradient—outward in the winter.
A cold surface does not radiate heat; instead, it draws energy from the room. Therefore, well-insulated walls are crucial to the energy efficiency of a solid-construction house.
It is easier to ensure a building’s airtightness in solid-wall houses than in wood-frame structures. Because of the homogeneous wall construction, weak spots and defects become apparent more quickly and can be corrected, ensuring that the building’s structure remains intact over the long term.
Well-built, insulated, solid-construction houses have a service life of many decades.
