Greetings everyone, 

   I have a weird question... On a non conditioned basement, many times I find tongue in groove pine strips on ceiling of basements and then a second layer of wood as the finish product. If foam insulation is out of the question, is there any real value on trying to air seal that basement ceiling before insulating? and if you do agree that it is worth the effort, then how would you go about getting that accomplished?

    Thank you for your observations, 



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I agree that conditioning the basement is by far the best option.  If you are going to insulate the ceiling you have to understand that the basement is now outside and you will also have to:

1) air seal the ceiling

2) insulate all walls and ceilings of the stairwell

3) weatherstrip and insulate the basement door at the top of the stairs

4) seal the cr*p out of the ductwork and air handler

5) insulate the ductwork to way more than the code required R-6 to 8

6) insulate the water heater with lots and lots

7) insulate all water pipes (and boiler pipes, if there is one) with more than the usual

8) build an airtight and insulated box under and around all traps that break the ceiling plane

And don't forget the ceiling insulation - either foam board between the joists foamed in place, then batts below, or foam board at the bottom of the floor joists, sealed tight including the edges, and with batts above to fill the cavity.

By the way, several of these items are very difficult to complete properly - DAMHIKT


Hey there Ed, 

    I appreciate you comments... this is an interesting case because this basement is cement floor, stone walls 3/.4 of a way, and the reason I would bring this basement into the envelop is because I want to stop the large air leakage that comes from the outside, which rigid foam board is amazing to accomplish just that... but since this space it is not used for anything but for a laundry machine, it makes sense to keep this basement unheated since it may be used 5 hours a week at most. So I think it is best to tight the ducts so prevent heating an unwanted area, insulate them to prevent heat loss to an unwanted area, insulate the water heater since it is electrical and it is in an unheated area... same with water pipes from water heater and boiler...  


Think of it as a part of the house that is not being used, but part of the house none the less.  With proper wall insulation (R-19 is my recommendation for our WZ4) and air sealing, there will not be much heating load from the basement - we see 68° with no registers in the basement and tightly sealed ducts.  Easier, cheaper, and mo-bettah than doing the ceiling, etc, etc

Ed our habitat project -mostly dirt floor...


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