GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter X Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Thermal Break Between Concrete Patio and Existing Slab

connorkatz | Posted in Energy Efficiency and Durability on


I am building a concrete patio that will extend off of an existing slab on grade foundation. Paso Robles, CA

I am wondering if it’s worth creating a thermal break between the existing foundation and the concrete patio. And if so how to do so without exposing the edge of rigid foam to the elements?

See attached pictures for a better description

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. PLIERS | | #1

    I’m not sure about the thermal break but you might want to slightly slope the patio away from the foundation depending on the rest of your landscape. If there is any way for water to end up at ground level besides roof you want it away from your foundation.

  2. Expert Member


    Unless you intend to add exterior insulation to the rest of your foundation walls there isn't much point doing it at the patio. There will be no more heat loss there than elsewhere. If you do add the foam it should extend up to the framed walls above. You can cover it with a flashing which extends over the top and down the face as far a necessary for protection.

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |