How do you insulate between floors inside a split-level house?

Jeanne Ambro
by Jeanne Ambro

I am currently installing a new ceiling in my family room and would like to know if I can insulate the ceiling to prevent heat transfer to the upper floor. I already know I could insulate for sound reduction, but I need to prevent heat transfer. The upstairs stays warm while the downstairs stays cool with the heat primarily rising toward the ceiling. At the moment I don't want to install ceiling fans, but I may eventually. What kind of insulation should I use? Should it be faced or unfaced? And what R-value should I use?

  8 answers
  • 2dogal 2dogal on Nov 14, 2018

    If you decide not to insulate the ceiling, (a good idea) the best thing to do is drop a ceiling fan in the stairwell. Keep it on low to force the air back downstairs. The stairwell is acting like a chimney and that's how most of your heat is rising to the second floor, not through the ceiling.

    • Jeanne Ambro Jeanne Ambro on Nov 14, 2018

      Actually a fan the stairwell won't work and I suspect the heat is rising thru the floor, so I was hoping to block off that access. I have ductless HVAC units in each room so my house is zoned.

  • Ebbjdl Ebbjdl on Nov 14, 2018

    Jeanne,. Go online to Home Advisor or Angie's List. You can trust these sights, because these contractors are check out and verified. The insulation will definitely keep the room warm. Buy the best insulation you can. The higher the ",R" number the better. Aloha!

  • Eva Bowker Eva Bowker on Nov 14, 2018

    I would suggest using spray foam insulation. It insulates very well and its also eco-friendly and beneficial for your house. Check this article if you want to read all of the benefits:

    • Jeanne Ambro Jeanne Ambro on Nov 16, 2018

      Eva, I really don't want to have to vacate my home and/or my family room to install spray foam, because from what I've heard and seen, it needs 24 hours to cure before the home is safe for occupancy. And I would prefer to use something removable in case it causes any adverse issues.

  • Bijous Bijous on Nov 14, 2018

    Hi. Your air ducts are probably not distributed correctly through the levels of the house. This and improper seer will cause the uneven distribution of cooling and heating. However, if you do want to insulate, use foam sheets rather than insulation batting. It's lightweight, easy to install and also comes with a reflective backing for greater insulation. Good luck.

    • Jeanne Ambro Jeanne Ambro on Nov 16, 2018

      Bijous, thanx for suggesting foam sheets, that sounds like a perfect DIY solution. I will definitely look into that.

  • Seth Seth on Nov 15, 2018


    Heat energy will flow from any warmer substance to any cooler substance in any direction. When people say "heat rises" that is only true for convection currents. Since the greatest temperature difference is not between floors, but between warmer inside air and colder outer walls (remember the family room in your split level is partially below grade and almost always colder than anything inside) you are actually loosing most of your heat through your walls if they are uninsulated and through your concrete floor. That's not to say you should not insulate between floors, but know doing so will not solve all of your heat loss issues.

    • Jeanne Ambro Jeanne Ambro on Nov 16, 2018

      Seth, your response makes the most sense, thanx. I do eventually plan on removing the wainscoting that is currently installed that covers the below grade foundation and I will definitely investigate that insulation and improve it. As for the rest of the house I know my exterior installation needs work, just haven't gotten there yet.

  • Bijous Bijous on Nov 16, 2018

    Hi Jeanne. Just a follow up. Careful about insulating below ground. You can cause moisture build up introducing a perfect environment for mold. Anything above ground should still have a breathable exterior too.

  • Blown-in insulation would work.

  • Mogie Mogie on Apr 03, 2023

    Sounds like the need for either a few ceiling fans or a whole house fan. The second option would work better but also costs more.