The question "CLT or brick?" is rarely that clear-cut in practice. Most of our buildings are in fact hybrid: every part of the structure is made from the material best suited to its task. Timber performs best where lightness, precision and speed are needed — reinforced concrete where soil, water or large concentrated loads have to be dealt with.
What is almost always conventional: the foundation
A CLT house also sits on a concrete foundation. Because the superstructure is light, the foundation can often be simpler and smaller than for a masonry house of the same size, but its role is just as important: it provides a precise, level, dry base for the structure. The millimetre precision of CLT panels is only worth something if the slab is built to matching tolerances.
The junction is the key: a waterproofing, capillary-breaking layer always goes between timber and concrete, and the plinth raises the timber structure sufficiently above ground level. This is the point that decides the long-term durability of the house.
Basements and below-ground spaces
Below ground the structure is exposed to constant soil moisture and earth pressure — clearly the territory of watertight reinforced concrete. The proven solution: a concrete basement or underground garage with a CLT superstructure on top. That way each material contributes its own strengths, and the light superstructure also loads the basement slab less.
Sloping plots and retaining walls
On a sloping plot the terrain has to be held back: retaining walls, embankments and stepped foundations are conventional, typically reinforced concrete structures. Our Isaszeg project is an example, where a bespoke retaining wall was built alongside a garden building. Here too the point is to handle the retaining wall and the building designs together, because drainage and ground conditions affect both.
Stair cores, lift shafts, bracing
In multi-unit buildings a common solution is a reinforced concrete stair core or lift shaft acting as a stabilising core, surrounded by CLT walls and floors. This can bring structural, fire-safety and acoustic benefits — but it is always a design decision for the specific building, not a general rule.
What to watch in a hybrid building
- Different tolerances. On-site concrete tolerances are larger than those of factory-cut CLT panels — junctions have to be designed to absorb the difference.
- Moisture. Fresh concrete releases water for weeks; the timber junctions have to be protected from it.
- Scheduling. Concrete needs curing time, CLT production needs lead time — the two have to be coordinated so the panels arrive when the base is ready.
- One party accountable. Two technologies mean two specialist teams; someone has to be accountable for the junctions as a whole.
Why this pairing works well with us
Because we know both worlds. Alongside CLT building technology, conventional building methods are part of our services too, and as general contractor we are also accountable for where the two meet. So there is no need to compromise: every part of the structure is made from what works best there.
If you are wondering which structure suits your plot, read our article comparing brick and CLT, or book a consultation.
