Hello. I would be grateful for your expertise and advice. We are building a small hotel. The idea is to have the concrete foundation raised one whole floor. Upon this foundation, we would like to build three stories of hotel rooms. 14 small rooms per floor - each room approximately 20' x 12' (see drawing for rough idea) I was thinking to make all walls structural SIP walls. There should not be much lateral movement and since the floor span would only be 12'. So in this case, I was wondering if the walls would support the structure without additional supporting structure and using non structural splines. We don't have any engineers here familiar with building with SIPs, but local engineers would have to sign off and therefore understand SIPS. I am concerned it would be over-engineered. There is no snow here and wind would be as low as you get anywhere in the world. It seems that the floor load could be designed at 2kpa, whatever that means.

Where will you be building this hotel?  Which SIP do you want to use?  That is, which company would furnish the SIP.  Different brands of SIPs have different properties that have to be considered when building any structure.

qna, Location is very relevant and wind is not the same everywhere, design criteria could be anywhere from 80 mph to over 200 depending on where in the world you are

I would use the metal SIP only for the exterior envelope and they should be applied as continuous curtain wall against the intermediate concrete floor slabs. The roof level could also be made of metal SIPs.

Building is in tropics. The Maldives. No tropical cyclones fortunately. I have not picked a particular company to supply the SIPs. I dont even know if SIPs will be the best technology for this. We are considering light guage steel as the alternative structure. Typically buildings are done with RC, but too much time and also cost is high here. JeffD, could I ask what the reason is for using SIP only for exterior envelope? You mean that it is only a cladding to an existing structure? I dont see the point of using SIPs if it is not part of the structure? Expensive way to insulate isnt it? Also, wouldn't I then have to clad the cladding with siding?

I find that there is a lot of low cost sandwich panels on the market. Like hundreds of suppliers from China can supply these metal and other sandwich panels. I would never consider using them for anything structural, but I did wonder if they could be used as a curtain wall (like cladding) - I think thats what you are suggesting, right?. On the other hand, I am asking about SIPs that are actually structural. I know that both of you (JeffD and Chris Cavala) sell structural steel panels from reading through these threads and I am happy that both of you replied. I don't mind hearing the truth - and if that is that it should not be used for this type of three storey then that is fine. But I am not looking to use them if they cant save me enough time/money on structural costs at least where I use them. By the way, could you please clarify if the reason that using them as structural walls throughout the internal and external walls is a technical reason or a cost reason. I could understand it wouldnt make sense on single storey, but I thought that it might be a good idea on three storeys to distribute the load over more structural walls - I would have thought it could even go higher than three stories the way I had suggested (that is I had more structural walls than needed). Will try to post wind speed/conditions when our engineer gets back to me.

@cmkavala our building is designed for wind speed of 38m/s or 85mph

Hi qna, Kindly send me your details I may be able to offer you some help on your project. I have used SIPs and various hybrids for over 35 years. [email protected] regards,

Posted By qna on 03 Jun 2013 06:25 AM
@cmkavala our building is designed for wind speed of 38m/s or 85mph

qna,
A quick web search for cyclones - Maldives shows that they were affected just last year, I think the final design should be for more than 85mph.
But design wise metal SIPs are capable of 3 stories tall and 140mph all on their own.
any higher winds or taller buildings would need to rely on a rigid frame
the channelside in Tampa has an 7 story building with steel SIP curtain walls
be glad to work with you on a workable design

@Fergie. Have sent you an email.

@cmkavala thanks for the information. I asked the engineer what speed we need to build for and he said 38m/s. I am pretty sure thats right. We get monsoon weather and it can get windy. But I grew up in Australia and even on its worst days a windy day here is nothing compared to Australia. I also dont know what the definition of a cyclone is, but if we did get a cyclone here, nobody here knew about it.

I am interested in the 7 storey steel SIP curtain wall. We have a 10 storey project which will be done in concrete frame. Water proofing is the biggest issue here, followed by corrosion). If we can get a waterproof, insulated curtain wall, it will be very attractive. With steel sips, my understanding is that it is not finished in itself (unless it is a warehouse/shed). But otherwise, it should be cladded. Could you please educate me on finishing steel sips. I am sure there is extensive discussion on this throughout this forum, so please feel free to just point me in the right direction.

@cmkavala one more point to add. I had earlier looked into finish on steel sips and found acrylic render could be used, but found that the cost of this was quite expensive.

Posted By qna on 03 Jun 2013 07:24 AM
@Fergie. Have sent you an email.

@cmkavala thanks for the information. I asked the engineer what speed we need to build for and he said 38m/s. I am pretty sure thats right. We get monsoon weather and it can get windy. But I grew up in Australia and even on its worst days a windy day here is nothing compared to Australia. I also dont know what the definition of a cyclone is, but if we did get a cyclone here, nobody here knew about it.

I am interested in the 7 storey steel SIP curtain wall. We have a 10 storey project which will be done in concrete frame. Water proofing is the biggest issue here, followed by corrosion). If we can get a waterproof, insulated curtain wall, it will be very attractive. With steel sips, my understanding is that it is not finished in itself (unless it is a warehouse/shed). But otherwise, it should be cladded. Could you please educate me on finishing steel sips. I am sure there is extensive discussion on this throughout this forum, so please feel free to just point me in the right direction.

qna,
I just sent you a PM,
a cylone is a hurricane

If you build a concrete or steel frame and need to cover it with non structural panels, consider shotcrete (with fibers) or stucco over EPS foam. No further wall covering is needed on either side.

Thank for the idea @jonr. For non-structural, I would prefer to use light guage steel and put cladding directly to that. On the inside, I was even wondering if we could apply closed-cell pu spray foam from the inside. We can get a Canadian brand manufactured in China at a low price compared to how much it retails for.

Regarding using SIPS as cladding for a multi-storey building. For the 10 storey building, I was thinking if a SIP panel wall, were able to support the self weight of 10 identical panels stacked on top of it, then it could basically be placed directly to the ground level concrete foundation and be stacked on top of each other all the way to the 10th floor. It would not bare the weight of any wall. So the only engineering task would be to fix that single wall to the RC column and beam concrete frame of the building. So the inside wall would basically be flush up against the outside column and beam edge of the building and fixed maybe with angle iron or something like this. We could then put 2" interior battens and fix dry wall and electricals. If the SIP panels were clip together (like in some metal SIPS) or even like those cam-lock SIPS, then there would be no need to do any installation on the outside of the panels at all (except maybe if the system that connected vertically stacked SIPS required it). Even better would be if we could use say 3 x 40' high panels, in which case we would only have 3 points were water could possibly enter the frame (assuming the side-by-side panel locking system was water proof). Basically, it would be like treating the entire envelope of the building as a freezer (except where doors and windwos are cut out).

qna.................... 7 story at channelside Tampa with SIP curtain walls .....................................

qna, Panels should not be used for main structure because of fire code restrictions. One would not want a multi floor multi tenant building being held up with sheet metal and foam. All dividing floors and walls should be constructed of materials that have assemblies that are fire rated. The exterior envelope of the building is a good use of Metal SIPs.

Jeff, we already have load bearing approval for 1 hour rated SIP assembly

Posted By cmkavala on 07 Jun 2013 08:06 PM
Jeff,
we already have load bearing approval for 1 hour rated SIP assembly

"Fire Performance Evaluation of an Unsymetrical Load-Bearing Foam Sandwich Panel Wall Assmbly in Accordance With ASTM E119-05a:
Standard Test Methods for Fire Tests of Building Construction and Materials
We have used for fire separation walls in duplexes, commercial wall separations and fire rated assemnlies on "zero" lot lines.

Posted By cmkavala on 03 Jun 2013 06:59 AM

But design wise metal SIPs are capable of 3 stories tall and 140mph all on their own.
any higher winds or taller buildings would need to rely on a rigid frame
the channelside in Tampa has an 7 story building with steel SIP curtain walls
be glad to work with you on a workable design

Chris, is that mph rating for walls and roofs or just walls?

If a SIP roof is attached with a screw every 8" o.c. at the wall connection and then at the ridge beam connection, I would assume it would easily pass a 140MPH wind load. Am I right?

Posted By Lbear on 09 Jun 2013 12:59 AM

Posted By cmkavala on 03 Jun 2013 06:59 AM

But design wise metal SIPs are capable of 3 stories tall and 140mph all on their own.
any higher winds or taller buildings would need to rely on a rigid frame
the channelside in Tampa has an 7 story building with steel SIP curtain walls
be glad to work with you on a workable design

Chris, is that mph rating for walls and roofs or just walls?

If a SIP roof is attached with a screw every 8" o.c. at the wall connection and then at the ridge beam connection, I would assume it would easily pass a 140MPH wind load. Am I right?

Lbear,
It is a general statement,
It applies too roofs, walls and floors as well.
There are many factors that enter into span capabilities and fastener schedules as they relate to MPH ratings,
such as roof configuration, orientation, design pressures positive and negative, wall and roof spans,overhangs, building "importance" ........ all enter into the analysis of spans and fastener spacings.
Depending on the spans 8" oc might work, but my quess is they would probably be 6" oc.
I currently have a completed 3 story design in north Pinellas county with 6" walls and 8" roof panels , 13 foot span - 150 mph, roof attachment at -8" oc., if the span was 15 ft. they would probably be 6" oc., but we will put them at 6" oc anyway,
In the grand scheme of things fasteners are cheap insurance, we usually go closer than the specifications

Does the thickness of the foam core make a difference in terms of strength? A 6" vs 12" core both spanning the same distance, attached at 6" oc, I assume the 12" core will have the higher load strength?

Also, when you mention "spans", are you referring to the spans where the SIP would attach/screw down to a beam? For instance, if you have a 25' SIP and you have it attached at 3 points or every 8' (ridge beam, center beam, wall). Would that be viewed as a 25' span or a 8' span?