Ceiling dropped/sagging (roof timbers) (Ed.)

[plugy]

We have a bedroom ceiling approximately 4.5 by 3m.
Towards the far end of our room, the outside gable wall, there are three joints that run alongside the wall, with straps on the outer sides screwed to the purlins. helping to suspend the span.
All the other joists run perpendicular to these three and appear nailed through the ends. Where this has occurred, all the joists have sagged approximately 4 inches at the point where they're nailed. (not helped with the old kid's stuff in the loft)
If we take the weight off would a strong back across the sagging joists work, and do these have to run the entire length of the ceiling so the ends sit on the inner brickwork? if so, don't think we would get them in. had been tols they dont need to sit on the briskwork just "float across the joists".
What is the recommended size for these timbers, and is it a case of simply screwing the joist up into this strongback?
Also, our loft is decked. Can you run the timber over the top of this, or do we need to strip the boards up so it sits directly on top of the joists?
I'm also guessing that as the deflection mainly occurs at the point where they are nailed and runs for only about 6 inches before it flattens, the joints may be beyond straightening.
What be the most cost effective way to sort the issue?

 

[securespark]

I can't immediately answer your question but I can help.

We had an issue with loft timberwork needing strengthening.

We were told by the roofers to take all the carp out of the roof space and not use it for storage so as not to put any extra load on the timbers.

So we emptied the whole lot out and had the space fully insulated.

It's a great excuse for a clear out!

 

[Deleted member 323070]

I suspect the original ceiling binder was removed to facilitate the installation of the loft boarding.

 

[aveatry]

I can't immediately answer your question but I can help.

We had an issue with loft timberwork needing strengthening.

We were told by the roofers to take all the carp out of the roof space and not use it for storage so as not to put any extra load on the timbers.

So we emptied the whole lot out and had the space fully insulated.

It's a great excuse for a clear out!

I often think about the amount of stuff in the attic after all a normal ceiling is built to only hold PB and plaster isn’t it. I have a rule that if something goes up then something has to come down.

 

[MNW67]

I often think about the amount of stuff in the attic after all a normal ceiling is built to only hold PB and plaster isn’t it. I have a rule that if something goes up then something has to come down.

Sensible rule! I wish I could be that strict.

From what I remember, it depends on how your roof is constructed. Ours was built specially to be used storage, so it is strengthened in some way.

 

[noseall]

We have a bedroom ceiling approximately 4.5 by 3m.
Towards the far end of our room, the outside gable wall, there are three joints that run alongside the wall, with straps on the outer sides screwed to the purlins. helping to suspend the span.
All the other joists run perpendicular to these three and appear nailed through the ends. Where this has occurred, all the joists have sagged approximately 4 inches at the point where they're nailed. (not helped with the old kid's stuff in the loft)
If we take the weight off would a strong back across the sagging joists work, and do these have to run the entire length of the ceiling so the ends sit on the inner brickwork? if so, don't think we would get them in. had been tols they dont need to sit on the briskwork just "float across the joists".
What is the recommended size for these timbers, and is it a case of simply screwing the joist up into this strongback?
Also, our loft is decked. Can you run the timber over the top of this, or do we need to strip the boards up so it sits directly on top of the joists?
I'm also guessing that as the deflection mainly occurs at the point where they are nailed and runs for only about 6 inches before it flattens, the joints may be beyond straightening.
What be the most cost effective way to sort the issue?

You could fix the ceiling binder in two pieces with a decent (bolted) overlap. It should sit on masonry at the ends.
125mm - 150mm deep. All ceiling joists twice fixed.