deck ledger board? on fire code house - Contractor Talk - Professional Construction and Remodeling Forum

sponge racing · 08-09-2009, 02:38 PM

Hey guys was looking at what some of you guys would do. Just built myself a new house and I need too make it fire code. So 2 layers 5/8 sheetrock on exterior walls inside then 1/2 in ply and 2 layers 5/8 gypsum sheathing on the outside. Im gonna use one 5/8 exterior sheetrock first then 1 layer of 5/8 Denseglass on the outer layer. I have a upstairs balcony and beneath that another balcony. So ? is should I put the ledger board right to the plywood or would you put the ledger board after the 2 layers of gypsum sheathing sandwiching it all together? Thanks

Joe Carola · 08-09-2009, 03:32 PM

Quote:

Originally Posted by sponge racing

Hey guys was looking at what some of you guys would do. Just built myself a new house and I need too make it fire code. So 2 layers 5/8 sheetrock on exterior walls inside then 1/2 in ply and 2 layers 5/8 gypsum sheathing on the outside. Im gonna use one 5/8 exterior sheetrock first then 1 layer of 5/8 Denseglass on the outer layer. I have a upstairs balcony and beneath that another balcony. So ? is should I put the ledger board right to the plywood or would you put the ledger board after the 2 layers of gypsum sheathing sandwiching it all together? Thanks

This isn't spec'd out on your plans? If not ask the Architect who drew them what to do for your area.

ScipioAfricanus · 08-09-2009, 04:56 PM

Wow! That is one heck of a fire code...uhh...code. I think that would be about a 4 hr. fire wall here in CALI.

If I remember right one layer of 5/8 Gyp. type X is rated for an hour. What is the time requirement you need?

Andy.

sponge racing · 08-09-2009, 06:18 PM

Ya not on the plans. This is a new rule for 2 communities where the houses are closer together. Not sure of the time. But definetly a pain in the ---. Also alotta wasted money and time.

Joe Carola · 08-09-2009, 06:28 PM

Quote:

Originally Posted by sponge racing

Ya not on the plans. This is a new rule for 2 communities where the houses are closer together. Not sure of the time. But definetly a pain in the ---. Also alotta wasted money and time.

The Architect has to know the new rules, ask him.

sponge racing · 08-09-2009, 09:27 PM

Will do that thanks again

edmontondecks · 08-10-2009, 10:11 AM

Here in Alberta, we are seeing the same changes to new construction. 2 layers 5/8 both sides here is a 4 hour wall. In order to maintain 4 hour rating or any rating, specified construction must be consistant throughout entire wall. As soon as you leave out for a ledger board or leave out for anything, the wall has lost its rating. I would say ledger goes over top...according to our rules up here. I guess you could just mark where studs are and send some longer bolts through?

www.edmontoncustomdeck.com

I almost forgot...with a 4 hour wall, all openings (on commercial here) must comply with fire rating up to 75% or a 3 hour opening. That means steel doors with closers etc. and virtually no glass. I would be curious to see what your architect spec'd for openings.

sponge racing · 08-10-2009, 06:49 PM

Asked him today and he said put the double 5/8 on then the ledger. Just seams kinda weird to have the sheetrock sandwiched between the ledger and the rim board. I used 2x6 walls so when finally done these walls are going to be 8 1/2 inches thick..

ScipioAfricanus · 08-10-2009, 08:18 PM

Quote:

Just seams kinda weird to have the sheetrock sandwiched between the ledger and the rim board.

That just doesn't seem right. wouldn't it be the same to attach the ledger to the studs, sheet the walls and the ceiling the same?

That would satisfy code here. Maybe I am not seeing things clearly though.

Andy.

edmontondecks · 08-10-2009, 11:58 PM

That is kinda...hmmm. Doesn't make sence. He could be giving you a "I want you outta my hair" answer. Remember, you are paying this guy money for a service. He should know this and with me being a non-certified architect, he should know better!

Question everything!

Sorry, he did want the 2 layer 5/8...then ledger. That make sence. I know it seems like you won't have enough support, but that is why you will have to send long lags into studs. So sorry, I blazed through the response and (I apologize) I was a bit hasty. Double 5/8 behind ledger is proper!

sponge racing · 08-11-2009, 08:07 PM

Yes he does want the double 5/8 behind the ledger. Going to use long bolts and drill the holes through all including the rim board. Thanks for all the help guys

Kgmz · 08-11-2009, 10:23 PM

What code is used in your area? IRC 2006, 2007, 2009

Look at:
R502.2.2.1
b. The maximum gap between the face of the ledger board and face of the wall sheathing shall be 1/2”.

h. Wood structural panel sheathing, gypsum board sheathing or foam sheathing not exceeding 1 inch in
thickness shall be permitted. The maximum distance between the face of the ledger board and the face of the

band joist shall be 1 inch.

You are over the 1 inch rule with just the double 5/8" gypsum, and not sure if you also have any plywood sheathing or a air gap behind the ledger.

Also don't forget R502.2.2.3, the 2 deck lateral load hold downs.

edmontondecks · 08-12-2009, 12:24 AM

I don't dispute any building code for your area, however, the building code is changing for fire regulations and sometimes they conflict. Here in Alberta, because of one large fire (google-macewan fire edmonton) codes are changing here as well. the building was under construction and the fire was huge...set by arsonist...maybe kids...who knows! Lots of surrounding homes burned as well.

Anyway, requirements for commercial/residential do conflict a bit. Very important to check with architect. Dot the "I"'s and cross the "T"'s.

www.edmontoncustomdecks.com

sponge racing · 08-13-2009, 07:06 PM

Very interesting, did put 1/2 plywood first for a nailer. I would be at 1 3/4 total thinkness to the rim board or joist. Will run it by him again thanks again.

Justbuilding · 08-14-2009, 02:51 PM

Another option might be to get a fire treated 2x and attach the ledger to that, not sure it it would work for requirements, that seems excessive, not disputing it, just wow!!

Framer53 · 08-14-2009, 03:17 PM

Quote:

Originally Posted by sponge racing

Very interesting, did put 1/2 plywood first for a nailer. I would be at 1 3/4 total thinkness to the rim board or joist. Will run it by him again thanks again.

Hey sponge, where in NY is this??

sponge racing · 08-14-2009, 09:40 PM

Bronx ny.. They had stopped issueing permits for like 5 months because they didnt want any new construction with wood on exterior walls. They were only issueing permits with steel framing or block and brick. Finally agreed on this 1/2 ply, 5/8 and 5/8 gypsum sheathing on exterior. And double 5/8 sheetrock inside also..

edmontondecks · 08-15-2009, 02:13 AM

To elaborate on maintaining fire rating...just picture, whatever you want to attach to the wall, inside or out, there can be no break in the double 5/8 fireguard/drywall.

The last post did give me an idea though. You could get a steel lintel made to spec to mount concrete block over 2 coarses? Concrete block here is a 4 hour wall. I know, it sounds like a headache because now your projecting another 8".

I don't know...just throwing that out there...it is late and I am tired.