recess ceiling - does it weaken the structure in any way?

has any one got any technical information if recess ceiling weaken the structure in any way at all?

what do you mean. Do you have a drawing?

I wouldn't have thought so? Surely the engineer on the job would structure the trusses to accomodate for the recessed portion?

I don't have any technical info but the recess is usually supported by more timber.
This is what they have done to my Kitchen. It has a drop and a recess. There are 10 timber beams that run across the top of the entire area so it is 350mm apart to secure the floor above. I would think this would be the same case as if we just had a recess and no drop ceiling.

no - i don't have drawing. still considering whether to opt for recess ceiling in entrerance or not.

hi starz - your recess ceiling is through dropped ceiling, so it does not effect joyces ( you can still see them running accross the top). but if ceiling is only recess ceiling, they cut the joycess. that is what i am wondering if that effects the strength

We have a recess ceiling in our entry and we haven't had any problems. I might have a pic of it at frame stage... I'll have a look.
They don't actually cut anything to do it... it's all purpose built around it.

i thought they cut it - i think i have seen in few houses being build in Perth. Pic will be good if you can.
thanks

short answer ..no
long answer .. no,no,no,no,no,no

relax, no one would approve a structure if it didn't meet regulatory building codes.

I can't see that engineers would continue to allow them if it weakened the structure

yes - i know it would meet regulatory building codes - but there is always a range of standards and the builder has to meet only minimum standards. once the minimum standards are met, it is approved. It is like plastering the new house. Sometimes there are so many dents etc in plastering and if you ask them, they say it meets the minimum standards that they have to maintain.

May be i should have said - effect the structure and not weaken. i think i should edit the subject title.

does any one any pictures at frame stage for recess ceiling in WA that i can have a look please.

This is the only pic I could find.... not too clear, sorry. Our entry is raised 30cm higher than the rest of our ceilings (I think) and it has the decorative bulkhead. I remember that the roof trusses were altered where it was raised, but it wasn't as though it was just cut, it was all built and braced properly. My boyfriend at the time is a chippy, he would have noticed if it wasn't right.
I'll take a pic of the ceiling tomorrow to see it when it's finished. I can't get in the entry at the moment, it was repainted today and it's blocked off so the dogs can't get up there.

This is at frame stage. You can see on the right, above the door frame, where the timber comes across, is braced, then drops down to above the door frame and that is the ceiling height through the rest of the house.

I understand where your coming from , just to put some perspective on the matter, most tradespersons will adhere to the maximum allowance e.g drill the largest acceptable hole in stud ..so in actual fact that stud then becomes the weakest permissible structure allowed, yet no one blinks an eyelid ..because it's acceptable according to the code.

If by recessed do you mean the appearance of a raised portion of ceiling. if so, then this is achived by actuall costructing additional timber bulkheads around (usually the outside of) a room. It is quite common for the kitchen ceiling to be dropped by 200 - 300mm, and then if a 500mm wide bulkhead is created around the room, then an illusion of a recessed ceiling is created.

have I explained adequately?

Coffered ceilings are designed using span tables to make sure that they meet all structural requirements.
If you are going to start questioning the structural integrity of a coffered ceiling then you may as well question the structural integrity of the entire ceiling, it's all constructed using the same principles and span tables.
The coffered ceilings I've done have been constructed using LVL's to span and hang the ceiling joists, there is no way they compromised anything, if anything I'd say the ceiling was more rigid than a standard ceiling.
By the way I'm in WA, but span tables and building codes are fairly universal (in Aus at least).

I think the OP is talking about a coffered (recessed central area) ceiling rather than bulkheads.
Fairly common in WA.

the entry ceiling is 28c but just in middle of that it is raised to 31c. it is not that the ceiling is 31c and then there is bulkhead around to create recess ceiling. does it make sense?

@cc101, see my post 3 up. It answers your question.