The cost of sending site spoil to landfill has prompted the creation of a new house foundations system formed from factory processed components.
The SystemFirst Homes foundation is made up of a grid of lightweight C-section steel beams, assembled on site to form a secure base on which houses can be built.
It avoids the need for the excavation of footings and the disturbance and removal of possibly contaminated soil.
Developed by foundation engineer Roger Bullivant, SystemFirst Homes is approved by the British Board of Agrement.
Last year saw the first two outings for SystemFirst Homes on a large brownfield regeneration scheme at Buckshaw Village in Lancashire and on a small residential development near Derby.
At Buckshaw Village a foundation for a terrace of five modular steel framed houses was created.
Steel-frame wall panels, complete with insulation and plasterboard, were brought to site, bolted together and secured to the predominantly steel foundation.
Roger Bullivant associate director Andy Preece says that major housebuilders in the North West, the Midlands and South West have shown a real interest in specifying SystemFirst Homes early in 2007.
'House developers are increasingly keen to specify foundation systems that reduce the burden they place on the environment, ' he adds.
'Developers working on brownfield sites in particular are looking to reduce the volume of spoil that has to be taken away.' A ystemFirst omes foundation rests on driven or precast concrete piles or vibrocompacted concrete columns.
Galvanised steel channels are used as floor joists supported by the foundation beams.
Sections of steel beam can be lifted by two site operatives by hand and the pre-engineered numbered pieces are slotted into place by following a detailed design drawing, produced by the Roger Bullivant in-house product design team.
Four combinations of shaped beam have been developed to spread load; external and internal support beams are complimented by a third detail to support a separating wall and a stepped beam can provide support for a garage threshold.
Steel sections are cut to pre-determined lengths before arriving on site and external beams are designed to span between, and be secured to concrete pile caps.
Panels of expanded polystyrene are then lowered into place between steel beams to provide an acoustic barrier and heat insulation, before a 40mm fibre reinforced concrete floor is poured and levelled.
Installing the foundation is followed by construction of either a brickwork and blockwork construction, timber frame, steel frame or modular panel structure.
'The purpose of SystemFirst Homes is to replace nonengineered, traditional house foundation methods on ground that does not require extensive treatment, but may still pose a problem, ' says Preece.