On 15/02/18 13:35, Andrew wrote:
On 15/02/2018 00:55, wrote:
What is the name for a beam where its "core" is made of a "zig-zag" of
metal and the top and bottom surfaces are made of (ply?) wood. Or is
that just bit of fake news, a product of a deranged imagination?


Standard fitment in all new houses. Much stiffer and stronger
so less of those creaky chipboard floors that 70's houses
suffer from.

The 22mm chipboard or t&g plywood flooring is glued on all
four sides and also glued onto the top section of the beam.

When the glue has set, they cut a hole where the stairs pass through.

Makes first fit electrics a lot easier, because there are no holes
to drill. I-beam versions where the web is OSB usually have knockouts
in the correct places.

Oh yea - an unliftable floor.

I know what else doesn't squeak and is nice and stiff:

7x1" boards screwed down to 8x2" joists