Use either extruded polystyrene (XPS) such as Styrofoam or Foamular or expanded polystyrene (EPS), sometimes called “beadboard.” EPS is less expensive and rates a… See more

Place the foam board directly again the concrete or block and secure it with adhesive or concrete fasteners and washers. Make sure you use an adhesive formulated … See more

If you are planning to finish the basement space, you should also consider adding a layer of foam insulation below the slab. The insulation may not save much money in energy bill… See more

It’s important to add a heavy-duty vapor barrier under the slab to create a barrier to water vapor, which can readily pass through the concrete. The water vapor will harm any p… See more