Hello, Ive been reading this forum for a while, and i guess its time for me to ask something. Im working in the early planning stages of a house build, to replace a house i have thats going to be torn down. Im in northern ohio, so I can see some pretty frigid times. I also live in the country with little windbreak so the house will take a beating pretty regularly. And my last concern is sound insulation, there is train tracks very close, and right now the sound levels inside the house are all but unaccepatable. Im looking at some SIP plans with R25 walls and R40 roof. I know this is far far more insulation than I have now, but Im wondering if this is enough for the climate and sound insulation that I need. So Im just wondering if anyone has any input, as far as alternatives or materials I can use along with the SIPs. I am on a pretty tight budget, so nothing too crazy for me. thanks!

Should be plenty for your climate. I have no idea about sound insulation.

When considering strength, insulation, air tightness, and especially sound control in a new home, Insulating Concrete Forms (ICF) are hard to beat.

SIPs aren't nearly as sound deading as denser materials like  concrete (or blown cellulose insulation), but at R25+ they're not nothing.  Even concrete isn't going to cut the deep rumble much but it'll cut the rattle clank & engine-roar considerably.

Dense-packed cellulose in 24" o.c. 2x6" stick framing will be quieter- twice the mass and a fraction of the mechanical coupling of a SIP.  And if you put 1" (R5) XPS foam on the outside of the structural sheathing it can meet (or occasionally beat) an R25 SIP's thermal performance. But it takes dedication to getting it as air tight as possible to really deliver. Play around with this tool a bit to convince yourself:

http://www.ornl.gov/sci/roofs+walls/AWT/InteractiveCalculators/NS/Calc.htm

If you design it with 1.5-2" of XPS on the exterior can pretty much beat an R25 SIP, but it's all in how well it was framed. "Advanced framing" details count.

Similarly, a framed structure with "energy heel" trusses to accommodate deep blown insulation has more mass than an R40 SIP, and will attenuate sound better, but needs full attention to air-sealing to make it perform without problems.

But whatever you do, don't neglect foundation insulation levels.  If the foundation isn't insulated it'll be 30% of your heat loss or more in a full basement configuration.  At the very least, pour the foundation walls in ICFs with at least R10 on the exterior.  Using un-balanced ICFs with the higher-R on the outside allows you to get a seasonal performance boost out of the thermal mass of the concrete.  Doing the whole house in ICF might make sense in some situations, but it's rarely the price-leader for those on a tight budget.

But if SIP it's gonna be, consider mass your friend:  Fiber-cement  or stucco siding will attenuate sound better than vinyl or wood clapboard/shingles, etc.  Using attenuating adhesives (eg "Green Glue" ) to install the interior gypsum, and using 3/4" material instead of 1/2"  (or dual layers of 1/2" cemented with sound-abatement adhesives) will also cut the sound considerably.  These measures are worthwhile with stick-build construction too (but with ICF, not so much.)

Also, independent of construction type, in windblown areas it's worthwhile to mount the siding with at least a 1/2 rainscreen gap between the siding and sheathing/SIP. Wind-driven rain & snow WILL find it's way under the siding, and having a rain-screen/drain-plane allows it to fall harmlessly rather than saturate the sheathing or siding. 1x2 furring is often used to provide the necessary spacing.  (You didn't ask, but I just thought I  oughtta mention it...)

Don't cheap out on the windows, they will also contribute to sound transmision, make dure you have a good insulated glass.
a furred airspace on the inside of SIP wall will help with sound transmission, proposed R-Value looks good

ditto what arkie said......

Agree, triple glazed windows are much quieter than double glazed.

Jesse wrote:
" triple glazed windows are much quieter than double glazed. "


Counterintuitively, this is not necessarily true.

from:

https://www.nrc-cnrc.gc.ca/eng/ibp/irc/cbd/building-digest-240.html

"Sealed Triple Glazing

Despite the widespread belief that adding another layer of glass must be beneficial, triple glazing provides essentially the same noise reduction as double glazing....."



The article mentions among other measures, that varying glass thickness is more effective than adding another layer of the same glass thickness.


Stephen Thwaites P.Eng.
Technical Director
Thermotech Fiberglass Fenestration

thanks all for the good info! I had looked into the ICFs for the main walls, but I think cost and DIY-able puts that out of my options. Dana - I like the idea of using my siding to help with noise, I will try to find something along the lines of what you were talking about. And also you mentioned a kind of adhesive for the interior surfaces, could you explain some more about that? thanks!

Interesting Stephen, I stand corrected. Perhaps it's the better gaskets and seals supplied with this quality of window that lead to that assumption.

You might consider staggered 2x4s (for a 6" wall) + foam for even less sound transmission than 2x6s + foam.

The one I'm most aware of is GreenGlue, but there may be others.  Third party test results using it in various wall layups are mostly downloadable here.

A dense rubbery sheet-goods/roll material that can be used to good effect is Acoustiblok.  They're one of many vendors of caulks & sealants with better than random caulking sound attenuation too. 

Any of these treatments require attention to detail (especially air-sealing and minimizing mechanical coupling) to deliver peak performance.  It's a budget issue too.

But for good/better/best using standard construction, generally speaking the more massive the material, the better the acoustic attenuation.  Of course there will be counterexamples to prove the rule. At equal densities different matierials may still differ- IIRC 2lb foam won't attenuate as much as 2lb ft^3 cellulose in the same cavity due to the mechanical rigidity of the foam, sort of a sand vs. ceramics at similar density- the rigid ceramic will transmit sound better than the granular goods.  But make it massive enough (like a 10" concrete wall), despite the mechanical coupling, there isn't much coming through.

If you're serious about this, you need to pay attention to sound transmission through ceilings & floors too.  Again, a foot or so of loose cellulose is a pretty good dual-feature material with higher mass & better attenuation than a SIP roof, but roof trusses, etc. provide mechanical coupling through the insulation layer, so vibe picked up by the roof's timpanic membrane aka "sheathing" can find it's way to the interior gypsum.  But the mass of slate or tile roof will take it down several dB too across some spectrum.

"GreenGlue" is actualy pretty amazing, I would not have believed how well it works had I not seen it myself. Be sure to read the directions and apply correctly, You want to use quite a bit of it on your drywall, even where the drywall does not meet a stud. We have a couple of sample boards in our office and the difference in sound dampening is shocking.

Double stud walls are very good at sound decoupling, but there isn't much that is going to cut the dull rumble of the train, because it is actually vibrating the ground, and hence your foundation. Another option is with any of the mentioned wall systems, put osb/plywood on the inside of the wall (if not using sips), then install drywall on a resilient channel, and put in a floating floor. The two things that are going to help you the most are mass and decoupling. About the windows, the best way to get good dampening is to use double pane windows, and put a storm window on the outside, but make sure the thickness of the glass on the double pane windows is different than the thickness of the glass in the storms. For example, if you use a double pane window with 1/8" thick glass, use a storm with 3/16" or 1/4" glass. You might consider building most of the house "normal", but in a select few rooms (like the living room and master bedroom) go through the trouble to really soundproof those rooms. I would suggest getting on amazon and getting an inexpensive used book on recording studio construction, It would help you more than anything, because they will show you a bunch of walls and the STC values of them, so you can really compare. (Most of the better ones are double stud or double concrete) I got a good book like this for about $15 shipped to me.