Ideas for SIP panel construction

I am building in the north of canada and weather is a concern. John has mentioned that he thinks SIP panels are good for heat but useless for sound. Lets call them not optimal. My situation is that i am basically isolated on the property from traffic and city noise, my only concerns are weather and the odd aircraft and maybe a loud bird or atv buzzing by. The idea i am having regarding building the shell of the studio is to use SIP panels for the outer structure. It's cheap and quick and i get instant angled walls and ceiling with the design, plus its big and very adaptable. this is just a rough design we are throwing around Once that basic structure is up my thoughts are to add an outer structure of a light 2x4 frame and attach plywood onto the frame. The frame would attacch to the panels using isolation clips. I would get an air space and the mass of the plywood and the roofing shingles working in my favour. Any thoughts on this approach?

so you would put an inside layer of plywood on isolation clips and cover with 2x 5/8" drywall over the plywood to create an isolation shell inside? :wink: that sounds reasonable especially for the live room. for the control room i wouldn't create the arch but if you can go up 14ft on a nice rectangular room, you will be in a good place... do you need to have a bathroom, lounge, airlocks etc? i'd probably create a small front section for those.

gullfo wrote:

so you would put an inside layer of plywood on isolation clips and cover with 2x 5/8" drywall over the plywood to create an isolation shell inside? :wink: that sounds reasonable especially for the live room. for the control room i wouldn't create the arch but if you can go up 14ft on a nice rectangular room, you will be in a good place... do you need to have a bathroom, lounge, airlocks etc? i'd probably create a small front section for those.

Thanks so much for the reply. That makes sense. The only troubling thought with the interior layer is losing the view of the nice beams. Could a similar system between the beams be designed and effective? Or would the breaks at the beams negate the whole deal? Yes the control room shape is just for placement and outer shell concept at this point. Although depending on price it might still make sense to box it on the inside and use the prefab shell that way, since it needs the extra layer anyway, if the shell is cheap.... That cr shell, with the 3 foot cement at the bottoms peaks at 16 feet. These guys have various beam sizes and panels to choose from and the architect is showing me ways we can use the existing sizes to fit my plan. There will be one air lock/iso booth and a drum room as you put in there in the main room, and also a little kitchen bath section too.

you could put the mass between the beams or possible on the outside of the beams but then run joists across/on the posts than to set the SIP on. this would put an air gap in place which would help with the isolation.

We are talking about ways to make the roof stc a bit better. One of the architect's ideas is to add an inner layer of 2x4 strapping with insulation in it over the inner layer of drywall. VB, then lay the panels on it. The added air space is small and the panel is still touching the inner frame with this design so i am not sure about it. Would this be worth the cost and how would it compare to just an extra layer of 5/8th's drywall in the inside leaf?

"The added air space is small " But it is a multiple. I would want more mass first then install treatments to the interior of the room rather than install more insulation (frankly redundant considering the performance of sip panels). As a matter of installation, I would think the added mass would be easier to achieve then attempting to develop a framing system below the roof panels that could support insulation and then added mass.

Thanks for the confirmation. I suspected that to be the case.

We are talking about ways to make the roof stc a bit better

You do know that STC is NOT a good way of measuring isolation for a studio, Right? STC does not tell you anything at all about how well the system will isolate low frequencies, which are the hardest to isolate anyway. TL (Transmission Loss) is a much better way to look at isolation for studios. - Stuart -

for in-between the beams i was thinking the mass is nearly flush with the inside of the frame and the SIP outside. leaving a larger air gap. the second option was if it wasn't possible... sounds like you could add the mass between. this example would need to be modified to accommodate the necessary air flow etc.

The issue with sip panels is that alone they have less ability to stop sound then say a typical interior residential wall...maybe 29ish on the stc rating. While they are effective at high frequency sound control, the sips envelope has little ability to control at low frequency. And then there is code compliance for separating the panel from the interior of the building with a specific fire rated material (usually in the form of sheetrock) attached directly to the face of the panel, contiguous I would think, but that would have to be verified locally. It might be worth looking into adding mass to the top side of the rafters then install sips panels, if it can be approved.

if i understand "mass to the topside of the rafters" correctly, then that is exactly the plan. The trusses go up, the drywall goes on the outside of them 1st and the panels sit right on the drywall, no VB no nuthin. If we build the said framing(with space and insulation) in between the drywall and panel a VB goes in. Mostly the concern here is to keep outside sounds out, and i realize that is the same thing almost as inside sounds in, but the priority changes a bit as the outside sounds will be occasional wind and planes as opposed to pissing off the neighbor regularly.

gullfo wrote:

for in-between the beams i was thinking the mass is nearly flush with the inside of the frame and the SIP outside. leaving a larger air gap. the second option was if it wasn't possible... sounds like you could add the mass between. this example would need to be modified to accommodate the necessary air flow etc.

I think i understand your picture but your description here is confusing to me. Are we on the same page as to the order of materials as my previous post above states?

Soundman2020 wrote:

We are talking about ways to make the roof stc a bit better

You do know that STC is NOT a good way of measuring isolation for a studio, Right? STC does not tell you anything at all about how well the system will isolate low frequencies, which are the hardest to isolate anyway. TL (Transmission Loss) is a much better way to look at isolation for studios. - Stuart -

Ok that makes sense. But the cement slab will have a 3 foot cement riser all around. The trusses will sit on the top of the 3 feet and then basically it's all roof(panels). Minus the gable ends which we are planning so far to frame out traditional 2x6 style. So the gable ends and the panels are pretty much the whole deal aren't they?

seaweed wrote:

if i understand "mass to the topside of the rafters" correctly, then that is exactly the plan. The trusses go up, the drywall goes on the outside of them 1st and the panels sit right on the drywall, no VB no nuthin. If we build the said framing(with space and insulation) in between the drywall and panel a VB goes in. Mostly the concern here is to keep outside sounds out, and i realize that is the same thing almost as inside sounds in, but the priority changes a bit as the outside sounds will be occasional wind and planes as opposed to pissing off the neighbor regularly.

I looked over the posts and do not see an actual square footage, but that isn't so much as needed. I can tell you this, you will be hard pressed to get folks up on a roof to install sheetrock that can break under weight of a small person...I don't know how or who you are going to talk into that. So it still remains that you could add mass in the form of 1/2" OSB then sheetrock and then the sips panels. This might make everyone happy or at best safe...especially the roofers out there in the cold and the wind and the snow :)

i think if there is no air gap you effectively have a directly coupled single leaf which will only have a couple layers of gwb (if we assume the SIP and 1/2" OSB have no significant isolation value) and therefore little attenuation of things like rain, trucks, yeti calls, etc... hmmmm... http://www.texsa.com/

What does that mean Glenn?

if we put the mass layer on the outside of the frame, then directly lay the SIP on the mass layer, does that not create a single leaf? if so, then we're missing a key part of improving the isolation...

gullfo wrote:

if we put the mass layer on the outside of the frame, then directly lay the SIP on the mass layer, does that not create a single leaf? if so, then we're missing a key part of improving the isolation...

It is a more massive coupled leaf, the exterior leaf, and if that >could< be completed in a less hazardous manner then the OP presented, would allow the interior of the building to be planned much in the same way you might do a warehouse or large barn. You have a heavy external leaf (isolation gets even better once roofing underlayment/shingles are installed) which is by nature of the sip panel a double sided coupled leaf. But since there is room to work with, the walls and internal ceiling framing would most likely allow for a large air space. But overall, I just look at these things from my vantage point as a guy that swings a hammer, owns nail guns and runs a circular saw so adding the exterior mass, if it can be approved by the architect, in the easiest installation manner brings down labor costs, reduces material waste and in this case will eliminate other steps required. I think they have their work cut out for them with the proper installation of the sip panels and, again, by design these things are comparable to an interior two-sided framed wall, so they have built in acoustic obstacles that have to be taken into consideration, in my view.

agreed...

Thanks for your input guys, i am waiting on the architect for some more drawings before posting more here. He seems to have an easy way to get the drywall on first, says you can even paint it first! I am yet to have it described to me, but a crane is involved in the assembly of the panels. It seems to make sense that at least the innermost layer be drywall just for aesthetics as that is the exposed, between the beams face. The beams are 8' apart on center I am leaning toward a couple layers of 5/8ths fireguard inside of the panels. The sip's have a layer of i think 3/4 osb on each side and they are filled with 10" styro. So in order to improve the situation i am wondering, if we stick with the single leaf concept and avoid the framing/air space idea, wondering if another layer of material between the 2 layers of drywall or the drywall and the osb on the sip panel should be considered. Any suggestions, like donna conna or plywood etc or is another layer of osb the best?

"He seems to have an easy way to get the drywall on first, says you can even paint it first!" Yea, you could spray paint the sheetrock and then screw the sheetrcok to the sip, which would eliminate the hazard :)

xSpace wrote:

"He seems to have an easy way to get the drywall on first, says you can even paint it first!" Yea, you could spray paint the sheetrock and then screw the sheetrcok to the sip, which would eliminate the hazard :)

So simple.

Simple until you try to mud and tape those joints and then prime and paint the final on it :)

not to mention all the caulking needed to ensure a good seal on the drywall layers... :twisted:

Thanks for sharing your thoughts on this everyone. It seems this avenue is a seriously wrong turn for studio purposes. SIP use for this application appears to simply waste money and creates superfluous work to compensate for their sound characteristics. I'm out. My new plan is here viewtopic.php?f=1&t=15096&p=106466#p106466 Please join in if you have any time or interest, it should be fun. Thanks again