Flooring a loft

[krieghammer]

Ok.... moved into a new house recently and one of the first things I want to do is floor part of the loft space for light storage items such as suitcases etc.

The insulation that has been installed by the house builder is about 300mm deep. The height of the insulation does go above the trusses by about 150mm max.

I fancy taking this project on myself, but need to seek some advice first to help work out the best way to approach it. I plan to use tongue and groove material as the main flooring medium.

My thoughts are... if I pressed the tongue and groove directly onto the trusses which would then give the insulation a downward force, would this cause the ceilings below to 'swell'?

Or, do I need to raise the floor above the insulation which would still allow plenty ventilation underneath and would also eliminate the pressure of insulation on the ceiling plaster board?

If the right approach is the latter idea, what is the best way to go about it?

My Collins DIY manual doesnt seem to cover this.

Thanks

 

[freddiemercurystwin]

This question has been asked about 4000 times already on the forum, have a look/search through the flooring section), fit say 100X50 joists at right angles to your existing joists (use screws not nails), stick your boards on top of these. The 150mm insulation will be happy to compress down to 100mm. 600 centres and 18mm chipboard will be fine. Keep anything you store in the loft evenly distributed and don't go mad with what you store up there.

 

[krieghammer]

Thanks.

Thankfully I have a garage to store heavier items in now. Did have a lot of weight in the loft in previous flat.

Sure, I'll carry out a search and see what I can find. Hopefully I can get a few example pictures of how to do it properly.

 

[CaptainTickTock]

Not an expert on supporting a floor, but I know that compressing insulation reduces its effectiveness considerably.

 

[masona]

As previous post, you're wasting your time to push down the insulation, if you've got gang nailed trusses then you need to do the layout of joists in a difference way