What is a Void (Double-Height Opening)?
A void is an open space that cuts through multiple floors — a gap in the floor of an upper level that creates a tall, open spatial experience. Through the void there is a visual connection between the ground floor and the floor(s) above. The space is not walkable at the location of the void.
What Makes a Void?
In a void, part of the intermediate floor is absent. The space of the ground floor runs directly through to the ceiling of the upper floor (or even the roof). This creates:
- Airiness — the space feels larger
- Natural light — roof lights or high-set windows illuminate the entire space
- Visual connection — residents on the upper floor can interact with the ground floor
Applications
| Application | Description |
|---|---|
| Hall/entrance with void | See-through space above the entrance area, staircase visible from above |
| Living room with void | Open connection to the upper floor, lots of daylight |
| Studio or workspace | Tall space for art, photography or bespoke work |
| Industrial living | Loft concept with open upper level above the living zone |
Void and Safety
A void always requires a balustrade or handrail on the open side at the upper level. Legal requirement (building regulations):
- Handrail height: minimum 1.00 m (for a void in a residential building)
- Baluster spacing: maximum 10 cm (to protect children)
- Material: timber, steel, glass or combination — approved for the load
Building or Enlarging a Void
When adding or enlarging a void in an existing home:
- Engage a structural engineer — the floor joists being removed are load-bearing; this must be compensated for
- Building permit — structural alterations often require a permit
- Remove or support floor joists — possibly install a steel structure
- Install balustrade — safety requirement
Closing a Void
Sometimes an existing void is subsequently filled in to create an extra room:
- Install a new joist structure
- Support from the existing construction
- Add finished floor and ceiling
- A building permit and structural engineer are also needed for this
Sound and Climate
A void can strongly affect sound and temperature in the home:
- Sound travels freely through the void — additional sound absorption (carpet, curtains, acoustic ceiling panels) recommended
- Heat rises — the upper floor can become warmer; good insulation and ventilation are essential
Related Terms
- Balustrade
- Floor joist
- Steel structure
- Loft apartment
- Rooflight
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