Mass Timber Construction
with the Thoma Holz100 System

Wood is not just wood. When processed correctly, it becomes an exceptional building material: sustainable, energy-efficient, health-promoting – and deeply comforting. This is both the credo and the mission of Erwin Thoma, founder and inventor of Thoma Holz100, the world’s first and only solid wood construction system entirely free of glue and chemicals. His vision: to build the healthiest and at the same time most durable homes in the world.

Natura Domicil consistently builds with the Holz100 system because it is not only an outstanding branded product, but also an uncompromising commitment to the environment, quality, and human well-being. Choosing a Holz100 home is not simply choosing a building – it is choosing daily quality of life, inner calm, and a tangible connection to nature. A true home for generations.

Thoma Holz100 is a solid wood construction system free from glue and chemicals, developed in Austria by Thoma Holz GmbH under the leadership of Ing. Dr. Erwin Thoma. It is based on the principle of harnessing the natural properties of wood – and perfecting them through innovative engineering.

In collaboration with independent research institutes, solutions are created that set new standards for climate-friendly construction, exceptional living quality, and a healthy indoor environment. This makes Holz100 a future-proof system – high-performing, proven, and continuously evolving.

The wood used for Thoma Holz100 comes exclusively from regional, sustainably managed forests  at altitudes of around 800–900 metres above sea level. It is harvested in winter at the optimal time – during the waning moon – and then air-dried for approximately one and a half years. This careful process makes the wood more robust, durable, and naturally resistant to pests.

The Holz100 system is a high-tech product of natureIt consists of multiple layers of solid wood stacked and cross-laminated, joined together using kiln-dried beechwood dowels – entirely without glue. The dowels swell within the surrounding wood layers, bonding the individual elements into a solid whole and creating a a permanently stable connection , much like branches within a tree.

Thanks to the layered arrangement forming a a closed structural force triangle , loads are distributed optimally. This purely mechanical connection is not only extremely durable, but also completely free of harmful substances – a milestone from both a building biology and ecological perspective.

So-called Healthcare Architecture deliberately relies on natural materials such as wood to create spaces of calm, safety, and well-being. Spaces that are not only aesthetically pleasing, but that actively support healing. Today, moon-phase harvested wood is known for its hygienic properties and has been shown to help reduce even multi-resistant germs and bacteria . For this reason, Holz100 is approved and ideally suited for use in clinics, hotels, rehabilitation centers, and similar facilities where health, recovery, and comfort are paramount. 

In a world that is becoming ever faster, more digital, more exposed to radiation, and increasingly overstimulating, the desire for retreat, calm, and genuine contact with nature is growing. Yet this is exactly what many people lack today – with noticeable consequences such as sleep disturbances, inner restlessness, and chronic stress. Experts are already speaking of a “nature deficit disorder”.

The good news: wood – and moon-phase wood in particular – can help.
Scientific studies show that living in solid wood homes has effects similar to those of regular walks in the forest: heart rate decreases, inflammatory processes are reduced, restorative sleep improves noticeably, and people feel a deep sense of comfort and protection.

The American biologist Edward O. Wilson called this phenomenon biophilia– our deeply rooted need to feel connected to the living world around us. Wood satisfies this need. It It calms, grounds, and supports mental well-being, helping to bring a piece of living nature back into our homes.
Solid wood is more than a building material. It is both an answer and a counterbalance in an over-digitalized world – a visual and sensory bridge to nature, whether in private homes, offices, or public buildings.

Holz100 wall types – the right thickness for every requirement

External walls:

• 36 cm – Maximum insulation performance without any additional insulation
• 30 cm – High thermal mass for optimal balancing of temperature fluctuations
• 25 cm – (Holz100 Thermo) Excellent insulation properties
• 20 cm – Ideal for fire protection with a space-saving design
• 17 cm – Cost-efficient, healthy, and fully functional

Internal walls:

• 14 cm – Load-bearing, stable, heat-storing
• 12 cm – Non-load-bearing, space-saving, sound-insulating

Ceiling panels:

• 17 cm – An economical solution for uncompromising solid wood construction
• 21 cm – For large spans of over 5 meters