A timber hollow-box panel is a prefabricated building element made of timber ribs with one or two face panels, leaving hollow channels in between. The parts are structurally glued into a stiff, lightweight whole that can serve as a floor or roof. Well-known systems are built from laminated veneer lumber (LVL). The version with face panels on both sides forms a closed box element; with a single face panel it becomes a T-shaped element, used mainly for floors.
Properties
- Lightweight — at around 110 kg/m², a timber hollow-box panel is considerably lighter than a concrete hollow-core slab (roughly 250 to 500 kg/m²)
- Large spans — depending on the system, spans of up to about 20 metres are possible
- High insulation value — the hollow channels can be filled with insulation
- Bio-based — it is a renewable building material with a natural timber appearance
- Airtight and stabilising — the element can act as a bracing diaphragm in the structure
Application
Timber hollow-box panels are used in timber construction for both flat and pitched roofs and for intermediate floors. Floors can be finished dry with a gypsum fibreboard or wet with an anhydrite or sand-cement screed.
Points to note
- Timber is moisture-sensitive; careful detailing and protection during construction are important
- Sound insulation depends heavily on the build-up and is usually lower than that of a concrete hollow-core slab; additional measures such as a floating screed may be needed
Related terms
- Hollow-core slab floor
- Timber construction
- Timber frame construction
- Prefabricated
- Glued laminated timber
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