COLUMN BUILDING SCIENCES FIGURE 4 Stem wall with horizontal and vertical insulation-foundation stem wall. Semirigid board insulation (mineral wool/stone wool or fiberglass). Note the requirements for damp proofing and sub-slab interior perimeter drainage for the stem wall when using these types of board insulation. Cladding Continuous Exterior Insulation Water Control Layer/Sheathing Protective Membrane Strip Also Acts as Capillary Break and Acts as a Termite and Insect Barrier Rodent Protection for Continuous Exterior Rigid Insulation FIGURE 5 Fiberglass rebar providing structural connection between stem wall and slab. Fiberglass Rebar Concrete Slab Cavity Insulation Gypsum Board Sealant, Adhesive or Gasket Sill Gasket Polyethylene Vapor Barrier Concrete Slab For Insect Protection Provide 3 ft of Mulch and Then Drought Resistent Plants Ground Slopes Away From Wall at 5% (6 in. per 10 ft) Damp Proofing Concrete Foundation Wall Rigid Board or Semirigid Board Insulation mineral wool/stone PHOTO 4 Fiberglass rebars-non-conductive reinforcing bars-awesome. Notice the big wool or fiberglass smile on the building science guy. layer from becoming saturated. This insulation layer can get intermittently wet as long as it is capable of drying. The granular layer and perimeter drain allow that to happen. What if I want to (or need to) structurally connect the stem wall to the slab? And not do it with thermal bridging and not do it with external perimeter slab edge insulation? Use non-conductive reinforcing bars-fiberglass rebars. Awesome (Photo 4). Figure 5 and Figure 6 show how they can be used. With the approach in Figure 6, the rigid insulation strip is installed with the penetrating rebar into the stem wall formwork prior to placing the concrete. The interior form has holes penetrating the form, positioning the 80 ASHRAE JOURNAL Stem Wall Geotextile (Filter Fabric) Granular Capillary Break and Drainage Pad (No Fines) Semirigid Board Insulation Mineral Wool/Stone Wool or Fiberglass Concrete Footing Below Frost Capillary Break Depth ashrae.org M AY 2020 FIGURE 6 Rigid insulation strip with rebar placed in stem wall formwork prior to placing stem wall concrete. Rigid Insulation Strip With Rebar Placed in Stem Wall Formwork Prior to Placing Stem Wall Concrete rebar. The rebar holds the rigid insulation in place while the concrete is placed. If you have bad soil conditions, you are going to end up with a monolithic slab/grade beam that may also be post tensioned. With these assemblies, the insulation can be installed on the exterior of the slab edge/grade beam extending vertically to the bottom of the grade beam, or it can be installed on the top of the slab.https://www.ashrae.org/