DIYbanter - View Single Post - semi-transparent floor

wrote:
I've forgotten to mention that there are joists (350mm gap)underneath
the sheets.
Poycarbonate is easy to handle and can be cut to size unlike toughened
glass.

But, in the case of a fire underneath, the polycarbonate will go in seconds.
I'd be looking at making a simple sloping foil-covered plate of 18mm thick
chipboard or something, that acts both as a reflector, to add great amounts
of light, and a fire door. Which can, on heat being detected below (hot-melt
glue or wax releasing a suspension rope) fall, and cover the opening.