very loud creaking in ceiling

eamon11

hello Folks,

the ceiling in one room is complete with joists and noggins. There is an upstairs also. No ceiling slabs or plywood for upstairs, have been laid on yet. However when I walk on the joists in this room upstairs, the creaking is unreal. Very loud and cracking. Just wondering, when its all slabbed and with plywood should this creaking stop? Its a bedroom and there will will be no sleep got if it remains so. I notice the noggins in this room do not seem as tightly fitting as the rest of the house.

thanks a lot

Bonzo Delaney

Sounds like the joists are flexing and if the bridging isn't tight they'll creak where the nails are. Are the joists the correct size for the span.? If it's bad now it'll be a lot worse when the building/ timbers dry out completely.
Personally I'd always recommend herringbone bridging great for counteracting any movement in the joists. But still not worth twopence if the joists aren't correctly sized.

eamon11

thanks Bonzo,

the joists are correctly sized and are the same as in the rest of the house.
Is there anything I can do now? The upper floor is of timber construction. Due to the type of renovation the joists at one end are not tightly fastened, just left on the internal leaf of a cavity wall. Would this make a difference? Or if I used some extra bridging now would it help?

Thanks again

Eamon

Tony Beetroot

You need to take the solve the issue where they rest on the inner leaf wall, don't get too caught up with any air tightness comments. Ireland is not Siberia.

Bonzo Delaney

If the bridging is loose that looks like your problem. Re do the bridging I'd still push for herringbone no more than 6 ft apart. If the span is more than 16ft I'd use 9x3s or detailed I joists depending on what the structural engineer specified. Are the joists built into the wall and the opes mortared in tightly. Air tightness is a seperate issue also. Nothing whatsoever to do with creaking joists. Screwed ply on top would help but I'd be only using it to "crown it" so to speak.

eamon11

thanks for the info Bonzo,

as I mentioned earlier,due to the type of renovation the joists at one end are not tightly fastened, just left on the internal leaf of a cavity wall. Would this make a difference? On the outside leaf rests the sole plate for the timber gable construction. The other ends of the joists are secured by joist hangers. This is a room which was originally a flat roof back kitchen.
My structural engineer is on holidays at the moment and unavailable for 2 weeks.
Just looking for ideas here.

Tony, you mention solving the issue of the joist on the wall. What exactly did you mean by this?

Bonzo Delaney

An extra two rows of bridging in About 12 inches from the ends of the joists should strengthen it up especially on the end sitting loose on the wall