New floor bounce

[23vc]

Thanks But tricky as got ring main and heating pipes going through most of em
Also sounds a bit extreme given I’m not exceeding the span so I’m a bit baffled.
Extra noggins are probably my best bet from the comments above

 

[Doggit]

But the C24 span tables show it's within the limits, so Noggins either end (about 250mm off the walls) should be okay. Offsetting the noggins like that, shouldn't cause an issue, but when you do the new ones, angle the screws in so they are all in line - and then redo the centre line if necessary.

 

[23vc]

Thanks good plan. On a related note does anyone know the ‘water glass test’ or something, I’m sure I’ve read about it as a way of seeing how bad the floor bounce is, along the lines of jumping up and down with a glass of water nearby (technical explanation)

 

[Notch7]

Thanks But tricky as got ring main and heating pipes going through most of em
Also sounds a bit extreme given I’m not exceeding the span so I’m a bit baffled.
Extra noggins are probably my best bet from the comments above

The span tables will still allow some bounce, the calcs are based on load and deflection.

Extra noggins should help stiffen it up.

Arr you laying ditra mat?

 

[23vc]

Arr you laying ditra mat?

Not looked at ditra mat but will check it out, I was going to do hardibacker over the ply to try and stiffen things up but if these noggins do the trick I may not need to

 

[Notch7]

Not looked at ditra mat but will check it out, I was going to do hardibacker over the ply to try and stiffen things up but if these noggins do the trick I may not need to

Now youve detected some bounce, its probsbly playing on your mind. I bet its not that bad, it cant be really since 6x2 over that dist is pretty sturdy.

And once the ceiling below is boarded the floor wont echo.

 

[Doggit]

The mat is more to do with expansion at different rates; don't think it's designed to handle vibration. Are you putting in any heating in the floor, as that would justofy the mat, but I think I'd be inclined to consider bamboo wood instead of tiles.

 

[23vc]

Cheers Guys given me plenty to think about

 

[^woody^]

Woody is that standard practice then, or more if the joists are only just big enough as mine might be

It's a standard requirement.

Have you also wedged the end joists off the adjacent wall?

 

[23vc]

Nope, as in wedged the gap between the bearer plate and the joist inside the hanger?

 

[23vc]

Sorry misread that, end joists are tied to wall with restraint straps and noggins. No wedges. That and the fact that it’s standard practice to noggin 3 times across the joist appears to have alluded my bco

 

[catlad]

I've walked on hundreds of flat garage roove's which are
generally constructed of 6x2" joists and they always
have some give in them, and that's decent timber
from 30-50 yrs ago not this stuff thats been polished
so you don't get splinters in you hands!
I was at a trade show recently and a guy from dunlop
was demonstrating a new flexible tile adhesive
very impressive.

 

[Doggit]

And is there a suitable grout to go with it, as that's what I find tends to go first.

 

[John D v2.0]

I sit at work between 4 pillars about 5m away in each direction, there's a corridor next to my desk. When someone walks past at the right speed sometimes my monitors are shaking and I can feel my chair bouncing.
I'd say it's excessive, but you can have a lot of deflection on such a big span because it won't crack the plaster.
The calculations aren't taking the glass test into account, they are worried about the plaster and tile finishes and of course the strength.

 

[23vc]

Yep, to be fair I should have been clearer that the bedroom floor doesn’t feel odd or particularly bouncy, it’s just that with a carpet you can’t really tell if it’s flexing too much. The ensuite is currently just ply floor, and it does feel a bit bouncy, but then again it’s empty and only got things like tools and hop ups in it. I just don’t want any cracked tile grout in the ensuite to ruin the job. Hoping a few extra noggins will sort it