Loft boarding question

[Jadava]

Hi all. In need of help please. Have recently moved in to a property and loft is partially boarded but I want to add more. The boarding is currently on these raisers but I have no idea what they are?
Would anyone please be kind enough to point me in the right direction.
Thanks in advance.

 

[freddiemercurystwin]

That looks like two slabs of 30mm thick phenolic foam insulation glued together (like Celotex) and then sandwiched between two layers of chipboard. I don't think you can buy something like that, I'd guess the previous occupier made them up, quite intuitive really, think I'd be a bit wary of stepping on them though. There's a board over the top of them presumably?

There a re few ways to crack tthis egg, you can use ordinary timber joists, loft legs or raised floor systems, there are literally hundred of threads on the forum showing how to board a loft eg https://www.diynot.com/diy/search/1749686/?q=loft+boarding&o=relevance have a read through some of them.