Why would you use a raft foundation?
A raft foundation is a reinforced concrete slab under the whole of a building or extension, ‘floating’ on the ground as a raft floats on water. This type of foundation spreads the load of the building over a larger area than other foundations, lowering the pressure on the ground.
What is a raft slab floor?
A raft slab is a reinforced concrete slab on ground that is strengthened with integral concrete beams in both directions. Usually, a raft slab is used as the foundation for new houses and extensions. … The beams around the outside are called edge beams.
How much does a raft slab cost?
Concrete Slab Costs Per Cubic Metre
Concrete slab prices range between $240 to $329 per cubic metre. Aside from the concrete slab cost per m³, you can expect your concrete contractor to charge approximately $60 or more per hour for labour cost.
How thick is a waffle slab?
They come in three thicknesses for use on different sites: 165mm – Suitable for “A” Soil Classification sites and special purposes* 225mm – Suitable for “S” and “M” Soil Classification sites* 300mm – Suitable for “M” and low “H” Soil Classification sites*
How does a raft slab work?
Raft slabs consist of a thick steel reinforced slab that is integrated with steel reinforced beams, which are dug into the ground for added strength and support. … It’s also more suited to sloping blocks as the edge beams are dug into the ground and working the slab into the soil and slope.