When we go shopping for food, we naturally check the quality of the groceries before we buy them. Strangely enough, when building a house, customers tend to focus 99% on the appearance of the building disregarding other important aspects.
Luckily, more and more people care about how their home is going to be built and wish to build only with environment-friendly materials.
One good example of such building material is MHM (Massiv-Holz-Mauer), a cross-layered wood panel where timber boards are joined together with aluminum pins.
MHM looks a lot like CLT (cross-laminated timber) but is produced using no adhesives or chemicals.
MHM panels are ecological, strong, stable, warm.
They are also rapidly manufactured, assembled and installed.
An eco-friendly solution
“When I ask my clients if they wish to build a healthy and chemical-free house, I have never received a negative answer” says Marek Mardisoo, product manager at EstHus (prefab-house manufacturing company in Estonia).
“I may sell building materials but in the process, I also help people to widen their horizons, reflect on the issues and develop an environment-friendlier mindset.”
According to Mardisoo, the production of such cross-layered panels allows turning less valuable timber into a first-class and eco-friendly building material.
As an added benefit, since no adhesive is used in the production process, all manufacturing leftovers can be used for heat production.
Strong and versatile walls
The panels are produced with millimeter accuracy ensuring extremely fast installation.
The holes and grooves for the utilities (electricity, ventilation, pipes) are milled into the panels in the factory.
In case something was not planned in the beginning and you wish to make some changes, it is easy to mill more grooves when the panels are already installed.
All this increases the efficiency on the construction site.
In case you wish to attach something to the wall, you will have no problems with MHM as the wall is exceptionally sturdy and fastening is simple.
Air grooves make the difference
Buildings made of MHM timber have a good indoor climate as the large adhesive-free wood panels regulate air humidity.
The panels also offer better thermal resistance as the air in the grooves improves the thermal conductivity by about 20%
Yes, there are groves in the timber boards that compose the panel. They are put in place especially to improve energy efficiency and soundproofing.
Soundproofing features are great because the soundwaves break in the air grooves within the panel.
Also, in MHM panels timber is not pressed together by force. Instead, it is allowed to remain relatively free, improving the elasticity of the panel and the consequent sound response.
No problems with humidity
Thanks to the air grooves, MHM panels are cross-ventilated and therefore more resistant to humidity.
Any moisture in the construction is first diffused within the panel and, after that, it starts to dry up.
This way, there is no risk of moisture remaining stuck somewhere (which can sometimes happen in case of various vapor-tight layers).
MHM panels do not require a vapor barrier. This helps to mitigate the risk of mistakes during the installation.
In fact, in the case of traditional vapor-tight constructions with films, there is always a risk that a tiny mistake by carpenters will cost you dear in the future.
MHM walls that come in contact with water by accident, will dry quickly and completely into their original state.
Unlike in other building materials, water infiltrating into the adhesive-free MHM material is immediately visible close to its entry point, revealing the location of the leakage.
Should the MHM panel suffer from permanent water damage, the affected area can be cut out and replaced with a new element.
Safer in case of fire
Characterized by very low thermal conductivity, MHM walls heat up slowly.
For this reason, the risk of fire spreading on heated surfaces or smoke transfer through the cracks in the wall is considerably diminished.
Aluminum pins provide the wall with enhanced strength and prevent the board layers from loosening.
In case of fire, the top layer exposed to the fire is charred and thus comes to function as a kind of a protective shield, slowly decreasing further charring.
Also, the absence of glue in the fibers results in no accelerant added to the fire and no toxic fumes released during combustion.
Although MHM is meant to be covered (usually with a wood cladding or various sheet materials or plaster) there have been interior designers who left the wood panels bare with no finish.
This way, a characteristic "industrial look" is given to the space.
Manufactured also in Estonia
MHM technology was developed in Germany in 2004. It is mainly used in the construction of private houses, semi-detached and row houses, but there have also been larger buildings such as restaurants, kindergartens and even a church.
EstHus factory in Estonia is the northernmost manufacturer of MHM panels in Europe and the only one in the Baltics and Scandinavia.
Article written by Liina Pulges.
Edited by Andrea Bronzini.
If you want more information or you have any other kind of question, feel free to reach out to us.