Any suggestions....

[Kilauea]

I went today to take some measurements and take some picts.I mentioned the engineer thing and he said hed look into it.What we talked about was the ceiling(the way it was built,I guess)could have a second floor on top.Wit this being said you would think that if it could hold that much weight on top it could support it on the weight(tiled ceiling) bottom as well,right?

Here are some picts,the studs are 16'' from center and the ceiling is only 10'.What do you guys think about 1/4'' hardie since there gonna be no traffic(hopefully)?I was thinking good(continuous)bond but light weight.No?Bad idea?What about denshield.Its light weight ,even in the 1/2''.But maybe that thin blue layer will eventually peel.And EZ would be even worse.????

[Kilauea]

"

[gueuzeman]

1/2" board (CBU). Almost no cost difference.

Hell, you could hang 4'x8' sheets of Azack and draw grout lines with a sharpie....

gueuze

[Kilauea]

1/2" board (CBU). Almost no cost difference

The price doesnt matter,Gueuze,its the weight Im tryin to curve...

[gueuzeman]

I don't theink the 1/4" is stifff enough. It will probably sag between joists.

3/4" plywood and ditra? LOL. Ditra ceiling. need more

gueuze

[crete51]

know ur all pros and dont wannna here this....1/2 ceiling rated drywall from national gyp its made to hold up on 24 centers with water based textures..
and mastic the tile

[HS345]

Art, can you link us to that information?

[crete51]

links are beyond me national gypsum . sumpen...high strength ceiling rated dry wall ...glue it and screw it ...will never fall down

[Dave Gobis]

1/2" requires 12" centers under code. I am with everyone else, get an engineer.

[The Kid]

After a consult from an engineer, I would look into one of the WEDI structural panels. Light weight, strong as hell, washers for fasteners which is big in my book. and a trusted product.

[jason1083]

http://www.nationalgypsum.com/submit...29%2000-06.pdf

It also says not recommended for high moisture areas.

Art:

Water based textures means something like popcorn texture or orange peel or that stucco looking plaster junk. Tile weighs considerably more than that. the weight (which factors in gravity) is probably close to 5lbs per sq foot

Mastic is not recommended for showers and is in no way going to make up for structural deficiency (no setting product can do this).

[G&B Plumbing and Tile]

Yeah, what Jason1083 said....

and just to give you an idea....

LIMITATIONS
• Not recommended for high
moisture areas: baths, saunas,
steam rooms. Prime with sealing
latex primer and allow to dry
thoroughly. Apply insulation
and polyethylene vapor barrier
(if used) before installing ceiling
board. Insulation not to exceed
2.2 lbs./square foot (8.5 kg/M2).
Adequate ventilation required.

notice 2.2 lbs of INSULATION... imagine 5lbs of tile/thinset/grout per sf on this board....

[Kilauea]

1/2" requires 12" centers under code. I am with everyone else, get an engineer

Wow,this changes everything.I was unaware that 1/2'' requires 12'' centers(this forum teaches me alot).What do you guys think about what Gueuze said about 1/4'' sagging?I agree with him somewhat but what if they went with something very light?I dunno Im more confused now then when I first started this thread,I mean I really wanna handle this correctly.Thanks to each and every one of you for giving me advice....

P.S.- Hey Gobis,Im assuming the code for 12'' centers for 1/2'' is code is ceilings AND walls,right?If so from now on should all shower walls (framed for 1/2'' substrate)have 12'' centers?And if so the main reason for this would be structural integrity?(need to know what to tell GCs)...thanx......

[HS345]

I believe it's only for ceilings LT.

[MudGuy]

Engineer is a good idea. TCNA indicates framing must be capable of supporting the weight of backer board and tile - 1/2" cbu = 6 lb/sf with 16" o.c. framing spacing, does not specify joist size.

2008 TCNA Handbook, C315-07, pg.56.

No 1/4" cbu and no mastic.