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Just curious, my local county is going to start requiring blower door testing starting later this year. I was wondering what kind of rating you guys have been getting on your houses? Have you noticed a big difference in ratings using products like Zip sheeting and spray foam insul?
 

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Sean
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Most builders have been building at 5 ACH or less for years now - by adding in the required air-sealing, many easily get below the 3 ACH required by 2012 code. Zip sheathing works great, same with changing the orientation of the sheathing, using larger sheets, etc...

Spray foam is completely dependent on the installer, I have seen some leak like a sieve, so make sure as soon as they are done you test it & then install the drywall
For more on ACH, blower door - http://blog.sls-construction.com/2012/building-science-ach-ach50
 

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diplomat
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You must mean 5ACH50, not ACH.

I generally get about 1 ach50 with traditional fiberglass and 6mil poly vapor retarder. All my air sealing effort is put into the poly, not the exterior of the house.
 

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been sealing the stud bays and caulking.... EVERY seam ...hell, been spray foaming between plates! .. once the VB is on right ....you could fill the place with water....add fish..
 

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diplomat
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1ACH50 is pretty good compared to most new construction. These are multi floor homes. Single floor homes are easier.
 

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Joseph A. Capece
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Rolling acrylic tape is manditory. It's pressure activated.
Absolutely. I was inferring that the roller should be used as opposed to a hammer handle, flat bar, 2x4 block, etc... Manufacturer won't honor their warranty unless they notice the diamond pattern left by their roller in the tape.
 

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I can't remember any numbers. What I do know is that after the first blower door test, I changed the way I did things, alot. My thinking turned to sealing. I was able to walk around the house and feel all the areas that were leaking air.
I think I learned more about where air is coming from.
If you have the opportunity to be inside a house during the test, take it.
 

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diplomat
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I can't remember any numbers. What I do know is that after the first blower door test, I changed the way I did things, alot. My thinking turned to sealing. I was able to walk around the house and feel all the areas that were leaking air.
I think I learned more about where air is coming from.
If you have the opportunity to be inside a house during the test, take it.
You are right. 1ACH50 houses are tight enough where you pretty much won't find anything, but you still will find small leaks from time to time and it can help you change your methods.
 
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