Illustrated Guide on How to Insulate a Monolithic Slab

A how-to guide for slab-on-grade foundations in either hot or cold climates

July 14, 2016
Use Z-flashing above the insulation to keep water out.

All illustrations: Dan Morrison

Combatting heat flow through a slab boils down to putting insulation over the biggest energy leaks, and one big cold spot on a slab-on-grade house is where the edge of the slab is left exposed to the outdoors. Review the step-by-step guide below, then read more about insulating monolithic slabs and watch an animation



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About the Author

About the Author

Dan Morrison is senior technical editor of, a sister site to Professional Remodeler.

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