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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Foam board on bottom (taped & sealed - if two layers offset all seams) & then blown in???

Depending on climate &/or conditions I might suggest you treat it like an encapsulated crawl instead - i.e. where are all the mechanicals

The mechanicals are in the basement. Oil furnace with hot air old metal ducts 

Are you also going to seal/insulate the stair walls and treads? What about the mechanical connections (plumbing, HVAC, electrical)? It's just too hard and I have not yet seen a basement that is truly separate from the "conditioned area" (it is regularly used as a laundry, craft or storage area). Just treat it as it is - part of the living area and seal/insulate the basement wall areas and band joist areas.

Basement is drafty because walls are 100 years old stone. Separating the basement from the house makes sense because the basement is too connected to the outside... I like Sean's comment of treating this space as a crawl space.. so then yes, it would be worth airsealing all the plumbing, HVAC, electrical penetrations as well.

Hello Luis,

If you seal the stair walls then your hvac connections will be affected. Consult a technician and seek more information about the hvac system and connections.

Mary... I read, and I read your post and I am not sure what do you mean... yes, when we air seal a home, and tight up the ducts, the furnace will work less... which is a good thing... not sure why would I need to consult to a technician.. Sorry, you lost me there

Spray foam & intumescent paint the interior of the foundation walls to air seal & insulate.  Seal & insulate the ductwork.  Mother earth is "giving" you 50+/- degrees alreadythru the floor so don't fret about the ceiling (1st floor floor) because its the wrong place to insulate just try to air seal the gross penetrations (stink pipe, chimney chase, big under tub / drain, etc.)!  We routinely see 25% heating cost redux in the NE with this approach.  If you try to seal & insulate the ceiling you may create an unintentional "terrarium" (condensation on FGB causes failure).

Find the Raccoon first !

While my leanings are towards Brian's camp, there is way too little information to provide any meaningful advice. 

Share more about the current conditions, project problems, budget, climate, uncorrected client biases and misinformation, and client objectives.

Luis, my house seems similar to yours. I'm following this thread and look forward to reading all the responses. --Bryan Gabriel (Charlotte, NC)


   I will then make sure to update as the work starts, including some photos... 

Luis, thanks for being open to sharing your experiences and photos of your project.

What is the "floor" material in your basement?  Mine is 10% concrete and 90% dirt, by area.


--Bryan Gabriel


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