Stack effect: Opinions needed

[Michael Roberson]

I recently visited a friends house under construction, and was giving him ideas on how to make his house more energy efficient. I suggested putting his attic access in his fully enclosed, unheated front porch to reduce the stack effect. (the trusses are open to the porch in the attic)

Do you think I made a good suggestion?

[John McKenna]

It might have been easier to just seal off and insulate the attic opening.IMHO

[David A. Andersen]

I can see how it would reduce leakage, but how do you figure it will reduce the stack effect?

[Michael Roberson]

Originally Posted by dandersen

I can see how it would reduce leakage, but how do you figure it will reduce the stack effect?

Im thinking of air leakage, if there were no attic access to leak, then the house would draw less air.

Am I fighting over straws?

[Marcel R. Cyr]

Originally Posted by mroberson

Im thinking of air leakage, if there were no attic access to leak, then the house would draw less air.

Am I fighting over straws?

Since this is the Thermal Imaging Thread, would the camera not show all the leakage of the access, lack of seal vapor barriers, leakage of pot lights, sealants missing at the rough framing and etc.?

[David A. Andersen]

I don't think so.
Most of the attic access openings leak like a sieve.

[Marcel R. Cyr]

Originally Posted by dandersen

I don't think so. What!
Most of the attic access openings leak like a sieve.

Would the camera not pick up all that I asked?

[David A. Andersen]

Am I fighting over straws?

I don't think so...

[John McKenna]

Originally Posted by mcyr

Since this is the Thermal Imaging Thread, would the camera not show all the leakage of the access, lack of seal vapor barriers, leakage of pot lights, sealants missing at the rough framing and etc.?

If the delta T is right, the answer would be yes.

[Chuck Evans]

Originally Posted by mcyr

Would the camera not pick up all that I asked?

Not sure if you want to attribute it to stack effect, but it certainly contributes greatly to summer heat gain & winter heat loss. Not to mention the effect of leaking unconditioned air into nearby returns.

[John McKenna]

Good image Chuck.

[David A. Andersen]

Great image and very nice web site!

I like your 10 questions...

[Marcel R. Cyr]

Pretty cool shot Chuck.
Thanks.

[Claude Lawrenson]

Depends are there any codes that may apply on a new house that might indicate an alternate location?

[Peter C. Russell]

The attic should be outside the conditioned space and therefore the pull down stairs should be as well. We isolate the stair with a 2X10 frame and insulate to R-38. When you pull the stairs down there is a piece of plywood with a handle facing you so you can lift the insulation out of the way when you come up the stairs.