In article , Michael
Walsh wrote:
The first was an engineered flooring joist it was made from 75mm
square timber frame with steel diagonal ties and occasional 75mm
square reenforcing. It came lengths up to 5M. It seemed like a good
idea as it allowed easy running of plumbing and electricals through
the joists without drilling as they were hollow and it is supposed
to have better flex and load carrying characteristics

Catnic tried an idea like this about 20 years ago. The diagonals were
V shaped galvanised pressed steel, with the ends and point being
stamped out to form nails like the plates used to assemble trussed
rafters and pressed into the top and bottom members in a similar way.
They didn't catch on.

The second item was a building block made from extruded clay it was
a sandwich of a 125mm inner block, 100mm polystyrene insulation and
75mm outer block. They are used alot in Finland apparently. They
are fixed using an adhesive rather than traditional sand/cement
mortar. They were very light but seemed flimsy to me.

I would wonder about the resistance to rain penetration. In some
respects a climate where it stays below freezing for months on end is
less demanding that our freeze/thaw driving rain winters.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm