Industrialised low-cost housing in the Netherlands
The industrialisation techniques used for this 70-dwelling project follow the architecture rather than determine it, and are only used where they are cost-effective. Cast-in-situ concrete 'tunnel-forms' are used for the ground floor, first floor and party walls of a dwelling, in this case a 'box' 10m deep and 4.8m wide. Before casting, all services are clipped to the reinforcement and all openings are framed. Three or four dwellings can be cast in one day. Computer- controlled heaters ensure overnight curing of the concrete.
The brickwork facades have a block inner leaf, in this case more cost- effective than cast in-situ concrete.
The pitched roof consists of a series of 200mm-deep insulated ply panels which span from eaves to ridge. They are craned into position and slot together. Rooflights can be included in the panel. The roof is then traditionally battened and tiled.
Other elements of construction are clearly defined:
the concrete balcony of two precast pieces, cast with neoplast formwork and fixed to the concrete floor slab
the ground-floor porch soffit is a precast beam faced with brickwork
timber windows and door frames are prefabricated into units.
As these elements are usually completed in one operation, larger tolerances are required and on-site detailing is not as fine as best UK practice, though manufactured components have a high level of finish. Compared to a uk building site, there are few people at work but each one is on the critical path. The building programme is highly defined and delays cannot be made up by increasing manpower.