3cm central ceiling sag over 8ft room noticeable?

[amandaeb]

Hello

I posted recently about my lath and plaster ceiling and plasterboarding. I've now removed the plaster(but not the lath), and can see the joists. (As people warned really, really, dusty job)

The joists in the middle of the ceiling are sagging along their length, this doesn't seem so noticeable, (12ft long) but crossways it does look noticeable to me. The edges of the ceiling are 3cm higher than the lowest point in the middle over the 8ft width of the room, (this tapers to 1.5cm just away from the centre) but only near the centre of the room lengthways.

I thought about attaching batons, but this would be difficult as they wouldn't need to be the same depth along the length of the room. (I hope this makes sense). I plan to use 3x6 plasterboard and get them skimmed.

One plasterer I had in talked about the summer beams coming loose and this causing the sag, I explained that I hadn't seen any other beams in the loft except the joists. I've tried google but i can't find out anything useful about them. Can anyone explain what these are please, do they run crossways to the joists?

My questions are, do you think this sag will be noticeable if the plasterboard is screwed directly onto the joists? (preferred option) Are the plasterboards flexible enough to accommodate this sag? We are planning to sell the house soon. The plasterer suggested plasterboarding then using some bonding to try to even it out a bit, but his quote was considerably more than others.

Would it be worth trying to fix some cross beams into the loft and trying to screw up from the ceiling joists into them to raise the joists again?
I read some past posts and considered lowering the ceiling with joist hangers, but I'd rather minimise the cost.

I dont know how noticeable ceiling sag is to people who don't know to look for it! Thank you in advance for any advice/ideas.

Amanda

 

[oilman]

Stop worrying, it's a ceiling not a billiard table. It would be better to replaster with laths replaced where they're broken and use lime plaster. That keeps the character of the house, but it's not the cheap option you're looking for. Some people might want horizontal ceilings, but then they probably buy carrots that were turned to identical size on a lathe.

It's a pity that people do all these unsatisfactory things to destroy the character of houses, and consequently their history, and then just sell them.

 

[JerryD]

30mm sag may not notice when it's all plastered. However, for the plasterer to apply bonding to try and flatten this sag should only cost about £150 (maximum) extra over just skimming.


What has he quoted you for this?

 

[masona]

One plasterer I had in talked about the summer beams coming loose and this causing the sag, I explained that I hadn't seen any other beams in the loft except the joists. I've tried google but i can't find out anything useful about them. Can anyone explain what these are please, do they run crossways to the joists?

Not heard of summer beams ! They are called blinders as you say goes across the centre (sometime 2 blinders depending the span of the room) resting on the ceiling joist nailed to the ceiling joists which prevent ceiling sagging and they rest on wallplate or through the internal wall.

 

[legs-akimbo]

You may notice it Amanda on the basis that you know its there!
i doubt anyone else ever would.
A good plasterer would be able to feather out the best part of the problem with bonding, and in truth if he paid particular attention to the ceiling lines where it is most apparent the ceiling would be as good as perfect, and probably better than many a new job where the plasterers have not gotten good straight ceilng lines.
In general theese are the things that catch the eyes attention if your ceiling lines, skirting lines and internal angles are dead on then the main bulk can be like a dogs hind leg but wont be noticeable.
I think you may mean binders masona,

 

[masona]

I think you may mean binders masona,

As you see my english teacher wasn't very good

Would it be worth trying to fix some cross beams into the loft and trying to screw up from the ceiling joists into them to raise the joists again?

Once the timber sagged, it will never go back to the original position.
Agreed with others best to leave it alone.

 

[amandaeb]

Thank you all very much for your repies. They have answered my questions brilliantly.

Amanda