What's best

[longdogs]

Hi

Sorry, I have read lots of posts on this forum and other forums but can't seem to come to a conclusion.

In general, when strengthening joists in a loft for light storage and occasional foot traffic (just putting stuff up there), is it better to glue and screw 4"x2" on top of the existing - or at right angles - or maybe both? Would doing both add to the strength or just add to the weight on the ceiling below?

I have 400mm joist centres. The area is about 6sqm and no supporting wall although roof is trussed. Ceilings are lathe & plaster. Existing joists are 3"x2"

There is evidence that someone has worked up there before, as it is, because one wall has been plasterboarded.

There seems to be conflicting advice on whether to fit at right angles or on top, so maybe both ways work just as well I'm not sure.

Any advice would be great.

Cheers!

 

[freddiemercurystwin]

Right angles every time, will distribute the loads more evenly, also, should you wish to do so, if you add a second layer of insulation into the new void you are creating it will create a better insulating barrier, the two layer being perpendicular to each other and minimising heat loss.

Don't bother with glue.

 

[longdogs]

Thanks fmt for a precise answer