2 story, 2x4 stud walls

**Chris Weekly** · 09-18-2013, 04:57 PM

2 story, 4 unit apartment building - over the carport, and crawlspace.
Carport area had steel posts supporting, but the front of the building with crawlspace underneath was all 2x4 stud walls at the perimeter.
When was it acceptable to frame the stud walls of a 2 story with 2x4s? .....this time obviously, built in 1958, stucco exterior, with interior diagonal wall bracing.DSC07503 (Small).JPG DSC07499 (Small).JPG DSC07551 (Small).JPG DSC07523 (Small).JPG

**Rick Cantrell** · 09-18-2013, 05:27 PM

Originally Posted by Chris Weekly

2 story, 4 unit apartment building - over the carport, and crawlspace.
Carport area had steel posts supporting, but the front of the building with crawlspace underneath was all 2x4 stud walls at the perimeter.
When was it acceptable to frame the stud walls of a 2 story with 2x4s? .....this time obviously, built in 1958, stucco exterior, with interior diagonal wall bracing.

Hi Chris
I don't have the codes with me so I may be incorrect.
2x4 studs are allowed even today.

**Chris McIntyre** · 09-18-2013, 08:10 PM

Don't know the code in 1958, but current code, IRC Table R602.3(5), 2x4's are not allowed "when supporting two floors, roof and ceiling". 2x6's are @ 16" O.C.

**Rick Cantrell** · 09-19-2013, 05:16 AM

Originally Posted by Chris McIntyre

Don't know the code in 1958, but current code, IRC Table R602.3(5), 2x4's are not allowed "when supporting two floors, roof and ceiling". 2x6's are @ 16" O.C.

Somehow I did not see the photos
Yes, you are correct 2x4's are not allowed if supporting 2 floors and the roof.
The photos show 3 story's (3 levels), Garage/ carport and crawlspace is level 1, and 2 more levels for the living space.
2x4 studs on the 1st level is not acceptable (using todays code).

So to answer your question, "When was it allowed?" I do not know. Sorry

**Garry Sorrells** · 09-19-2013, 05:33 AM

Originally Posted by Chris McIntyre

Don't know the code in 1958, but current code, IRC Table R602.3(5), 2x4's are not allowed "when supporting two floors, roof and ceiling". 2x6's are @ 16" O.C.

Doesn't look like 2x4 supporting upper 2 floors. Posts and Beams carry loads. 2x4 in carport are just filler walls.
so:
TABLE R602.3.1 MAXIMUM ALLOWABLE LENGTH OF WOOD WALL STUDS EXPOSED TO WIND SPEEDS OF 100 mph.........

HEIGHT

(feet)

ON-CENTER SPACING (inches)

..................... 24 . ....... 16 ..

Supporting one floor and a roof
.>10............ 2 × 6...... . 2 × 4

**H.G. Watson, Sr.** · 09-19-2013, 07:30 AM

A four-family 2-story apartment building would not have been built to a 1-2 family code.The history of California "Codes" can be found on a State-sponsored web site.Separation walls and partition walls at the foundation level nor in corrodors are being confused.The structure and construction type is being miscategorized by the OP.

**Chris Weekly** · 09-19-2013, 11:13 AM

Originally Posted by Chris McIntyre

Don't know the code in 1958, but current code, IRC Table R602.3(5), 2x4's are not allowed "when supporting two floors, roof and ceiling". 2x6's are @ 16" O.C.

That's what I was going on, but taking into consideration that this is 1958, things were different...
I just found my 1955 UBC.

The carport area (rear of building) with 2 storys above = 3 storys
The front of the building is upslope, higher ground, and therefore = 2 storys - according to the last sentence of the definitions....
...and then section 2507 (b) 2. says... "two stories or less..not less than 2"x4" studs... "

Thanks for all your input. It's great to have a forum to bounce around ideas.

**Thom Huggett** · 09-23-2013, 10:46 AM

Two things about this building stick out to me:

This looks like a soft-story building, which can be subject to collapse during an earthquake. It looks like you are in Northern California, so you are probably familiar with what happen in the Marina District during the Loma Prieta EQ.
The steel pipe columns are non-combustible, but don't appear to be one-hour fire protected. There is a difference. They must be fire protected to support the one-hour floor-ceiling between the garage and units above, even if they are non-combustible.

**Chris Weekly** · 09-23-2013, 02:12 PM

Originally Posted by Thom Huggett

Two things about this building stick out to me:

This looks like a soft-story building, which can be subject to collapse during an earthquake. It looks like you are in Northern California, so you are probably familiar with what happen in the Marina District during the Loma Prieta EQ.
The steel pipe columns are non-combustible, but don't appear to be one-hour fire protected. There is a difference. They must be fire protected to support the one-hour floor-ceiling between the garage and units above, even if they are non-combustible.

Hello Thom - yes I called out the soft story aspect to the buyers in my report. I see these types often in inspecting here in the bay area. I know that SF and Oakland have mapped out the addresses with suspect buildings of this type construction. The surrounding cities though may not necessarily have flagged buildings in their own areas. This building is in Fairfax, and I don't know how concerned the city engineers are with notifying owners.
The one-hour aspect of the metal posts did not appear to be an issue at the time due to the age of construction. How might you have approached the subject? Not required at time of construction, and not relevant...Not required, but upgrade recommended....required upgrade regardless of age of construction???

**Thom Huggett** · 09-24-2013, 02:36 PM

Originally Posted by Chris Weekly

Hello Thom - yes I called out the soft story aspect to the buyers in my report. I see these types often in inspecting here in the bay area. I know that SF and Oakland have mapped out the addresses with suspect buildings of this type construction. The surrounding cities though may not necessarily have flagged buildings in their own areas. This building is in Fairfax, and I don't know how concerned the city engineers are with notifying owners.
The one-hour aspect of the metal posts did not appear to be an issue at the time due to the age of construction. How might you have approached the subject? Not required at time of construction, and not relevant...Not required, but upgrade recommended....required upgrade regardless of age of construction???

Chris, As a plan checker I would have required it at time of permit issuance. It would have been required even in the 50's under the UBC, but small towns did/do not always have a professional plan check and inspection staff. Depending on who your report is addressed to you might just make it a recommendation based on the current building code.

**lukerabun** · 09-30-2013, 10:09 AM

Just trying to Educated myself here on this firewall issue mentioned. I think I understand this correctly that the metal post is an issue because is doesn't meet the 1 hr fire wall rating required for the living space above it. So my questions are:

1. How would it be done correctly in new construction?

2. How would this be corrected in this situation?

Thanks in advance for your time.

**Thom Huggett** · 09-30-2013, 02:48 PM

Originally Posted by lukerabun

Just trying to Educated myself here on this firewall issue mentioned. I think I understand this correctly that the metal post is an issue because is doesn't meet the 1 hr fire wall rating required for the living space above it. So my questions are:

1. How would it be done correctly in new construction?

2. How would this be corrected in this situation?

Thanks in advance for your time.

Yes, when you have a one-hour fire rated ceiling the members supporting it must also be one-hour rated. The answer to both of your questions is either wrap the posts with lath and apply 7/8" stucco, or frame around them and apply 5/8" type 'x' gyp board to the framing.