Insulated Raft Slab

This interlocking foundation system by Isoquick is laid to form a ‘bath’ for concrete to be poured in to, while creating a cosy wrap of insulation. This wrap of insulation avoids heat loss and can leave many thinking a Passive House has underfloor heating.

This type of system relies on an area of reinforced concrete for a structure that spreads the load of the dwelling evenly across the footprint of the ground floor.

Whereas traditional foundations rely on digging trenches to fill with concrete and focusing the load of the walls directly beneath where they are built, this system ensures even ground pressure, ideal for particular ground conditions where normal footings are not optimal.

An insulated raft slab is typically more expensive in material costs compared to alternatives but when labour costs and speed are factored in we believe this is the best solution. Used during a recent project the client has chosen to have a polished concrete floor as their finished floor surface providing even greater savings and time, providing them with a warm surface underfoot.