we hang entire metal frame / drywalled ceilings from panel skins, if need be, thru bolting works too

Posted By cmkavala on 12 Feb 2012 09:57 PM

It would depend on weight of hood and thickness/span of panels

What are the SIPs rated at for weight/load?

I assume a SIP that has been furred can carry the load of 5/8" drywall and a wood T&G ceiling without bowing or failure, correct?

Posted By Lbear on 13 Feb 2012 02:00 AM

Posted By cmkavala on 12 Feb 2012 09:57 PM

It would depend on weight of hood and thickness/span of panels

What are the SIPs rated at for weight/load?

I assume a SIP that has been furred can carry the load of 5/8" drywall and a wood T&G ceiling without bowing or failure, correct?

Lbear; again thickness and span will dictate allowable loads.............
Send us your plans and we will engineer a workable solution...
concentrated load needs to be dealt with differently than the overal spread out roof/ceiling loads.
Does the hood weigh 500 lbs or 2,000 lbs.? where is the hood loacted? in the middle span?
near the ridge?
Near a bearing wall?

Posted By cmkavala on 13 Feb 2012 06:20 AM

Lbear; again thickness and span will dictate allowable loads.............
Send us your plans and we will engineer a workable solution...
concentrated load needs to be dealt with differently than the overal spread out roof/ceiling loads.
Does the hood weigh 500 lbs or 2,000 lbs.? where is the hood loacted? in the middle span?
near the ridge?
Near a bearing wall?

We are looking at around 130 - 150 LBS

As of now, I don't know the exact location of the hood but once the plans get more finalized, I will have that info.

When they furr down a SIP ceiling and install drywall, how do they install the furring pieces into the SIP? Is it just with a screw and how far does it go into the SIP itself?

Looking back at the specifications, that vent hood can actually be converted to a DUCTLESS system, but I wonder how efficient that would be. They utilize charcoal filters and then return that air back into the home.

Lbear; unless its just the angle of the photo, the hood in the picture looks more massive than 130-150, but if thats all it is , there is no problem 150# is the weight of a small man, no engineering needed.,Just some additional stitch screws in furring

Posted By cmkavala on 13 Feb 2012 05:54 PM
Lbear; unless its just the angle of the photo, the hood in the picture looks more massive than 130-150, but if thats all it is , there is no problem 150# is the weight of a small man, no engineering needed.,Just some additional stitch screws in furring

The weight of those vent hoods is basically all in the base of the fan/motor assembly. The ducts are just hollow, while a longer duct will weigh more than a shorter duct, it is just hollow sheet metal.

Do you have any pics of a SIP ceiling that was furred? I would be curious to see how they furred the ceiling.

http://www.myspace.com/steelsips/photos/15587200#%7B%22ImageId%22%3A15587200%7D

I would avoid poly except in extreme heating climates. Punctures let moisture in the wrong spots and trap it. I believe in redunancy for air barriers. Whereever you have an opportuinty use and air barrier. Gaskets are better than caulks, expanding foam etc.

IF you have a basement then I would assume that you have HVAC in the basement. IF that is the case the basement should be inside the thermal and air barriers. With your talk about isolating the basement I am concerned that you are not planning subslab insualtion and basement wall insualtion. You need to start at the subslab. Insulate under the slab R10 rigid. Poly can be placed over the rigid insulation and act as moisture barrier for subslab moisture.

Spray foam should be used to seal the band joist/sill plate overlapping the foundation and the floor sheating.

Posted By Roberth on 14 Feb 2012 01:17 AM
I would avoid poly except in extreme heating climates. Punctures let moisture in the wrong spots and trap it. I believe in redunancy for air barriers. Whereever you have an opportuinty use and air barrier. Gaskets are better than caulks, expanding foam etc.

Do you mean "avoid" polystyrene that are in a Steel SIP? Who are you referring/talking to?

polyethylene

The poly always goes against the ground - from which the moisture originates in a basement. If you foam the basement you have a barrier. If you glass the basement, the wall should be poly and the glass open to the room.

The poly always goes against the ground - from which the moisture originates in a basement. If you foam the basement you have a barrier. If you glass the basement, the wall should be poly and the glass open to the room.

I use the following sequence for a basement slab:
Earth sloped to drain to daylight,
6" minimum of clean tamped gravel,
2" Polystyrene,
Waterproofing membrane,
concrete slab.

Building scientist that I follow say that the waterproofing membrane should go directly under the slab and not under the polystyrene.  Your local code official can advise you as to what he will accept.

Posted By cmkavala on 18 Feb 2012 07:10 AM
polyethylene

What is the Steel SIP made out of?

Posted By Lbear on 18 Feb 2012 07:59 PM

Posted By cmkavala on 18 Feb 2012 07:10 AM
polyethylene

What is the Steel SIP made out of?

Lbear;
we'r talking apples & oranges,
Poly is ployethylene, is visqueen, is plastic sheeting, like zip lock sandwich bags/or a plastic vapor barrier under a slab
SIPs core (steel or otherwise) is EPS = Expanded Poly Styrene, is styrofoam

Posted By cmkavala on 18 Feb 2012 09:14 PM


Lbear;
we'r talking apples & oranges,
Poly is ployethylene, is visqueen, is plastic sheeting, like zip lock sandwich bags/or a plastic vapor barrier under a slab
SIPs core (steel or otherwise) is EPS = Expanded Poly Styrene, is styrofoam

Understood.

In regards to steel SIPS and their seismic resistance. Engineers refer to a "continuous load path"  when it comes to seismic resistance.
What makes them so good/strong when it comes to seismic loads? In a roof application with ICF walls and a Steel SIP roof, the lateral shear loads will put side to side loads on the home. How does a steel SIP resist that load when an ICF wall is trying to pull and push on a SIP roof?

Posted By Liebler on 25 Jan 2012 11:56 AM
In planning my "dream house"  I have been giving a lot of thought to and researching how to reduce air leakage.  The airtight drywall approach + an exterior envelope that's well sealed as well to reduce "wind washing" of the insulation (dense pack cellulose) is what I'm planning.  The devil is in the details...

Liebler, I'm rather late responding to your original post, but here it is FWIW. I'm in the process of building our home and have become quite passionate about air sealing and insulation. Others on-site might assign another description to my attentions to this issue. ;-)

Some of the products/techniques used on our build were a good quality sill gasket, taped zip sheeting, casement or awning windows (instead of DH), bulk quantities of high quality smoke/acoustical sealant with a pump sprayer, high quality air sealing tapes, air tight electrical boxes, and metal duct work (ventilator) with 2 coats of mastic. My limited experience (owner builder) has been that some of the air sealing got done by subs at the correct stage (i.e. during framing) and a lot of it I'm doing (some of it at the right time and some as 'catch up' after the fact). In some ways building your own house (we're doing electrical, plumbing & HVAC ourselves) is frustratingly slow ... but in other ways I welcome the slower pace of my labor and my husband PT on long weekends because it gives me the calander time to work on airsealing while my husband is at work during the week. Some of the efforts are a learn as you go, and require research, testing, and sometimes redoing. My labor is cheap, many of the materials are not really that much in the scheme of the overall project - but the time is takes is a lot (at least DIY).

The Jan 2012 issue of The Journal of Light Construction (JLC) has a very good article on air sealing tips by a contractor who does this work on a daily basis. I highly recommend it as background reading.

Good luck with your "dream house".