Google review
ZTC built my house in 2012, and they have done some reclamation work in two periods since then. Only positive experiences with ZTC! Good quality of workmanship and customer support.
A+ energy performance
A+ energy-efficient timber house
A+ class is whole-building performance — not wall thickness alone. ZTC delivers the structure and panel solution according to the project and energy audit.
ZTC experience and production facts
34+
years of experience
400+
completed projects
14
European countries
±1 mm
CNC precision
Wall thickness alone does not guarantee A+
A+ energy performance depends on windows, orientation, thermal bridges, airtightness, ventilation with heat recovery and the heating system. Wall thickness of 250–400 mm is chosen according to the project and energy audit. See energy-efficient timber houses and cellulose insulation.
A+ class: project and ZTC delivery
A+ class is determined at whole-building level. ZTC provides timber structure, insulation and membranes according to scope, while an independent certified specialist carries out the energy audit at design stage.
- ZTC responsibility
- Construction delivery
- Project / audit side
- Energy audit
- Wall thickness
- 250–400 mm
Manufacture and assemble the structure according to the approved project and scope.
The energy audit at design stage determines appropriate wall thickness and systems.
Depends on project, insulation and energy audit requirements.
What influences A+ class
- Windows, orientation and thermal bridges.
- Ventilation with heat recovery and heating system.
- Building form, airtightness and assembly quality.
The exact solution is determined in the energy audit at design stage — not from a wall thickness table alone.
What clients say about ZTC quality
Google reviews highlight ZTC’s precision, organised process and professional communication.
Google review
Ļoti profesionāls un ieinteresēts darbs no ZTC puses, lai maksimāli izpildītu klienta vēlmes mājas būvniecībā, ieguldot laiku visu detaļu precizēšanā, kā rezultātā pašas būvniecības laikā neko nevajadzēja koriģēt un ir tapusi patiesi kvalitatīva māja. Atzinīgus vārdus par mājas būvniecības kvalitāti saņēmām no visiem speciālistiem, ar kuriem sadarbojāmies vēlāk - liekot logus un durvis, jumta segumu un apdari. Paldies par paveikto un varam tikai ieteikt citiem izmantot ZTC pakalpojums māju būvniecībā! Pateicībā, Irēna un Janeks
Typical influencing factors
Wall construction
250–400 mm depending on project and audit.
U-value
Approximately 0.12–0.15 W/m²K depending on solution.
Airtightness
n50 < 0.6 possible with quality execution.
Ventilation
Heat recovery is important for whole-building energy performance.
Energy audit at design stage
An energy audit is carried out by an independent certified specialist at design stage. This helps compare solutions before production and assembly. ZTC delivers the structure, but the A+ class result depends on the whole building solution.
Estimate your indicative budget
The calculator helps compare scopes and prepare an initial budget guide before project review.
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View projectRelated topics
- Energy-efficient timber housesEnergy-efficient timber house solutions with ZTC structures, insulation and airtightness requirements adapted to the project.
- Cellulose insulation in timber housesCellulose and wood fibre insulation in timber houses: industrial Isofloc system and energy performance context.
- Timber house priceIndicative timber house price ranges and the factors that influence a ZTC offer for a specific project.
Frequently asked questions
Questions about A+ class, energy performance and price.
Would you like an energy-efficient timber house?
Send project information to review structure and scope.