This is how I would build a four story load bearing metal SIP structure.

Yes it is. We are currently doing a 4 story SIP apartment project in Las Vegas. Seismic category D. All four walls levels are made out of self supporting SIPs.

oops wrong pic, here is the one I wanted. Multi Story EPS CladnBuildings are all over Las Vegas. The taller structures use some steel for added structure

Can you post some pictures?

Yes I can. Here are three pictures of the apartment with self supporting SIP walls attached.

Jbeason1;

Awsome!


Guess that blows Haddock's theory that it does not meet code

Brucew;

4000 lbs per linear foot based on what wall height?

Jbeason1;

Nice photos. Great project. Do you know how the four stories was achieved. For example doubled/tripled splines, doubled plates etc. Anything you could tell us would be educational. Thanks

All exterior walls needed to be 1 hour fire rated from the inside so double top plates and 4x posts every 4', as the panel connection, were used. Along with 2 layers of drywall on the inside of the wall panels, to achieve the 1 hour rating. Although this had very little to do with the axial loading on the SIPs.

I am considering a four story house, but with an unheated garage as the first floor. Would a stick built (2x8, 16 oc) first floor be adequate to carry the 3 SIPS floors above?

Posted By thomassargent on 10 Oct 2010 10:51 AM
I am considering a four story house, but with an unheated garage as the first floor. Would a stick built (2x8, 16 oc) first floor be adequate to carry the 3 SIPS floors above?

It may, or may not, depending on a lot of factors. It is a question that needs to be addressed with an engineer and a full set of plans

It is not possible to answer your question. Since the loads placed on the structure are in large measure a function of the location of the structure, we need to know where it is to be built. Snow, wind and other loads must be computed before we know how much load the first floor must support. There are numerous four store wood frame structures around the country so it can certainly be done; however, to suggest that a framing size 2x8 and spacing 16 in. is not safe. It may or may not be correct and the only way to know is to understand the design loads and design to that loading within the scope of the relevant building codes.

I live in Galveston and here we are concerned about wind load. Wind load not only increases with height, it also is dependent upon the geometry of the structure. This and other loads are what must be considered before the structure can be adequately designed.

Matt Phelps! They've been looking for you around here. There is another thread in the SIP forum "Can't find Matt Phelps"

Wow! Well thank you, I think!

thomassargent,

I would build the first floor out of concrete block w/ many reinforced/filled cells. If I were designing the first floor in wood framing, studs may have to be 12" o.c. and sheathing may need to be applied to both sides of the wall. Given the four stories you may be beyond the efficient use of wood framing for the first floor. Also, there will be loading issues at the garage door opening(s) to resolve.

Matt and Jeff, Thank you for your input. I am in Maine so snow load is more a factor than wind. The structure would be 24 x 36. I was wondering about how to best carry the load over the garage doors? With using concrete block would ICF be acceptable?

That would depend on many things. But usually a normal convention floor system can carry the weight of the SIP walls above. Our SIPs with OSB skins and an EPS core are very light.

Posted By Jbeason on 11 Oct 2010 04:38 PM
That would depend on many things. But usually a normal convention floor system can carry the weight of the SIP walls above. Our SIPs with OSB skins and an EPS core are very light.

I don't think the question was about floor systems, it was about the first level wall framing of a 4 story building..... the way I understood it anyway?

ICF would be great. In my opinion it is just as strong as block. Make sure you have at least 16" of wall over the garage door opening to get enough rebar and concrete in the header beam. You might even need a 24" beam.

The header above the garage door should carry the load with out exceeding the deflection tables from the IRC.  I think the allowable deflection would be L/360, where L is the span length in inches.  Some span lengths are short enough that two 2x12 can carry the load, other lengths require engineered lumber such as I-joist, PSL, glulam, or a flitch beams.  We have used steel I beam on some longer spans in wood frame structures.  A precast lentil would also be a possibility, or a bond beam in CMU block may also be possible. 

Please be aware I do not know any details regarding your house so please do not take my comments as a design recommendation.  I, or no other engineer should ever make design suggestions with out knowing the details of the structure in question.  None of my comments should be construed as a design recommendation.

I think you should hire a competent, local structural engineer.  I mean you no disrespect when I tell you this is not "do it yourself" type work and the risk of catastrophic failure is simply to great to risk doing this type of work.  The cost of a good local structural engineer is only a few pennies of the total cost per ft^2, and yet has the potential of being the highest return on your housing investment.

All the best,

Matt B. Phelps, P.E., R.S.
Island Engineering
Galveston, Texas 77550