Lowered ceiling to create a 300mm recess feature around ceing to wall perimeter.

[Wilson78]

So we've used 3x2" cls.
And created a timber perimeter 300mm all around the rooms ceiling.
So the central ceiling area is lowered by 3" & when plastered, will have downlights in it, while around the ceilings perimeter is now a raised feature.
Trouble is because the cls are 2.4m long & the room is 12meters, we have butted up all the lengths , which is 5 lengths each side of the rooms length.
The rooms width is 2750 so we had a few 3meter cls timbers for that.
We used a string line & where possible, measured 300mm off the walls to timber.
Giving us a start line to run all the lengths along nice and straight.
But with the cls not 100% straight & not all the walls plaster boarded, we have noticed our timbers look like they've been on a Stag night & are ****ed.
No laser = BULLSHIT.
We spend all day adjusting. Then as you know .....adjust 1 thing , throws summit else out.
Any bright ideas ? Apart from get someone else to do it.
The timbers spanning between the cls runs either side of the ceiling are 2750mm , so imagine putting joists In , all same lengths. But still it looks ****ed, cos of bowed timbers I guess, & 2mm here & 2mm there .
It all adds up .
What yeh saying?

 

[Wilson78]

It's easy for me to picture the job, but I appreciate my ramblings may be hard work to picture.
So imagine a rectangular room that has a 300mm wide walkway all around the rooms edges, which is also 3" lower than the rest of the rooms floor.
Now wack that on the ceiling

 

[freddiemercurystwin]

Not quite following tbh but should have used a laser to set the sight lines and used a metal system from the likes of British Gypsum rather than timber because then everything is dead straight. You just can't buy timber that's dead straight end of.

The other problem with fancy features like this is that existing ceilings and walls are generally all over the place which would have been obvious if you'd stuck a laser level on any of it beforehand..

 

[Wilson78]

Not quite following tbh but should have used a laser to set the sight lines and used a metal system from the likes of British Gypsum rather than timber because then everything is dead straight. You just can't buy timber that's dead straight end of.

The other problem with fancy features like this is that existing ceilings and walls are generally all over the place which would have been obvious if you'd stuck a laser level on any of it beforehand..

No mate, everything you mentioned is Spot on.
I also was aware of all those 'Pit Falls' you mentioned above, but I 'Hold my Hands Up' those 'Variables' within the existing house, made the job VERY TOUGH.
There was no real datum to take consistent accurate measurements from.
Some walls are brick, some plaster board, a stud wall that's fitted too far back.
So every moment were fighting.
Also cls from Wicks is stored upright.
So you have to select the best.
Now about Laser We shudda had 1.
School boy error expecting the other guy to sort it.
Lastly, we used a string line, a Alluminium box section & the longest level 2meters maybe
Then we took about 200 measurements , trying to average out the discrepancies.
Oh well....been told off Fair do's.
Btw what's the 'Metal System?'
Do you hire it ?
Thanks

 

[Wilson78]

Sorry ...
Metal system .
The metal stud system..i get it now

 

[Notch7]

Is this a shop or something, a room 12 metres x 2.75m is a bit strange.

personally I would e used long timbers if you could get them in the room, easier to straighten up.

A laser is essential.


Your problem is likely to be the a mixture of setting out the new and working with the existing .

did you screw you 3 x 2 direct to the existing ceiling or level up with shims - if the ceiling undulates it will also make the 300mm feature look uneven.

and you need to check the existing walls - how much do they undulate



People don’t realise how difficult modern features are - the trend for a margin around door openings and floors with no skirting or architrave is a nightmare