Energy Savings Through Thermal Insulation

An energy-efficient SetWood residence consumes up to 70% less energy for heating and cooling compared to a conventional building. 

For a 120 m2 home in Attica, this translates into approximately 70% savings on winter heating costs and up to 70% on summer cooling costs, delivering significantly lower utility expenses year after year.

Timber is a natural thermal insulator due to its cellular structure, exhibiting very low thermal conductivity (lambda ≈ 0.12 W/m K).

SetWood builds upon this inherent advantage by combining a structural timber frame with mineral stone wool (Rockwool), OSB sheathing, and gypsum plasterboard to create high-performance multi-layered wall assemblies. The result is an envelope characterized by exceptional thermal performance, low thermal transmittance (U-value), elevated indoor comfort, and reduced energy demand for climate control—yielding a more sustainable, cost-effective structure.

Here is an overview of the two key metrics governing a building’s thermal insulation:

The thermal conductivity coefficient (lambda) defines a material's ability to conduct heat.

The lower the value, the higher the insulating performance, effectively minimizing heat loss through the building envelope.

Materials with low lambda ratings, such as timber and stone wool, enable energy-efficient structures that deliver elevated indoor thermal comfort with minimal energy demand.

Unit of measurement: W/(m K)

The thermal transmittance coefficient (U-value) measures the overall rate of heat transfer through an assembled building element, such as an exterior wall, roof, or floor slab.

Calculated across the entire composite cross-section, the U-value serves as the primary benchmark for thermal insulation performance: a lower U-value indicates superior insulation and minimal building energy loss.

Unit of measurement: W/(m_² K)

The SetWood wall is an advanced multi-layered building assembly featuring an engineered timber frame, 100 mm or 150 mm integrated mineral stone wool insulation, and high-density OSB and plasterboard linings.

The naturally low thermal conductivity of wood (lambda ≈ 0.12 W/(m K)), paired with the thermal properties of stone wool (lambda ≈ 0.035 W/(m K)) and an engineering detail that breaks thermal bridges, delivers an exceptionally low U-value and energy performance superior to conventional masonry walls.

Thermal bridges are structural weak points where interior heat escapes, resulting in major energy losses.

Consider how a refrigerator operates: it maintains low temperatures only when its perimeter gasket seals airtight. In the exact same way, an energy-efficient building functions optimally only when its exterior thermal envelope completely eliminates leakage paths. 

SetWood’s engineered assemblies mitigate thermal bridging to yield a fortified envelope that guarantees thermal protection, year-round indoor comfort, and minimal energy overhead.

With SetWood’s advanced timber systems, thermal losses are designed out to maximize real-world energy savings.

Build a structure backed by premier thermal performance and low maintenance demands. 

Book a consultation with our engineering team to design your sustainable project together.