Building a timber house in Türkiye
From a holiday home on the coast to an apartment building in the city: timber construction is becoming a serious alternative to concrete in Türkiye. This guide shows what matters.
- Wall thickness
- 160–320 mm
- U-value W/(m²·K)
- down to 0.12
- Element width
- ≤ 16 m
- European approval
- ETA-25/1030
Which regulations apply?
For a timber house in Türkiye these rules are the most relevant:
- Timber building regulation (R.G. 32499) – design, calculation and construction of timber buildings, in force since 1 January 2025
- Turkish Building Earthquake Code TBDY-2018 with the implementation communiqué of 1 March 2026
- Zoning regulation (Planlı Alanlar İmar Yönetmeliği) as amended on 1 July 2026
- Building Inspection Law No. 4708
The process in five steps
This is how a timber house with CL-THERM prefabricated walls comes together:
- 1. Design by the architect and choice of wall thickness (160–320 mm)
- 2. Structural design by the structural engineer to TBDY-2018 and the timber building regulation
- 3. Shop drawings: every wall element with openings and connections
- 4. Production of the elements in the factory and delivery to site
- 5. Installation of the walls, followed by roof, services and interior finishes
Which wall thickness fits?
Wall thickness mainly determines thermal performance. According to the data sheet, CL-THERM 160 reaches a U-value of 0.366 W/(m²·K), CL-THERM 240 0.230 and CL-THERM 320 0.168 W/(m²·K) – for the wall element alone, without additional layers. With extra external wood-fibre insulation, wall build-ups down to 0.12 W/(m²·K) are possible.
The right thickness depends on climate zone, energy target and structure – inland regions with colder winters differ from the Aegean coast.
Fire safety and durability
Untreated, CL-THERM achieves fire class D-s2, d0 to EN 13501-1; it is designed to EN 1995-1-2 with a charring rate of 0.65 mm/min. Depending on wall thickness and lining, load-bearing walls achieve up to 120 minutes of fire resistance (REI 120, known in Germany as F120). The planned service life is at least 50 years and can be exceeded considerably under normal conditions. Structural weather protection matters: CL-THERM is designed for service classes 1 and 2, i.e. for protected building elements.
Your partner in Istanbul
BOI Bau Orkestra International, based in Istanbul-Beşiktaş, stands for AI-supported, high-tech load-bearing wall panel systems of superior quality. BOI brings CL-THERM to Türkiye and supports you from the first enquiry through planning to the delivery of the prefabricated timber walls – on request also turnkey. BOI works with world brands such as Lamborghini.