http://www.buildingscience.com The High R-Value Foundation Assemblies are summaries of the results of BSC’s ongoing High R-Value Enclosure research — a study that BSC has undertaken for the US DOE’s Building America research program to identify and evaluate residential assemblies that cost-effectively provide 50 percent improvement in thermal resistance. daily 1 2011-03-25T08:05:02Z http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-1-uninsulated-foundation-wall-and-slab This summarizes an uninsulated basement even though the code requirements in DOE climate zones 4 and higher do not allow an uninsulated basement in new construction where the basement is conditioned. The uninsulated basement was included as a baseline for comparison purposes only. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T21:30:37Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-2-code-minimum-r10-continuous-insulation According to the IECC, new residential construction of conditioned basements in DOE climate zones 4 and greater must be constructed with continuous R-10 insulation or R-13 in a framed wall. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:12:37Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-3-r13-fiberglass-batt-2x4-framed-wall This is another alternative to the minimum code required basement insulation in DOE climate zones 4 and higher. This construction uses a 2x4 framed wall against the concrete foundation with R-13 batts in the stud space. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:14:00Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-4-xps-2x4-wood-framed-wall-fiberglass-batt This insulation strategy is similar to High-R Foundation 03 but with the added insulation value—and moisture control—of 1” of XPS between the framed wall and concrete foundation wall. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:16:59Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-5-xps-foil-faced-polyisocyanurate When constructing with plastic board foams, the building codes require that the foam not be left exposed as a fire hazard. Thermal barriers are required over both board foams and spray foams in many cases. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:18:32Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-6-closed-cell-spray-polyurethane-foam Closed-cell spray foam provides very good continuous thermal control. Spray foam is an air barrier, so convective looping and air leakage thermal losses do not occur. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:20:08Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-7-open-cell-spray-foam Closed-cell spray foam provides very good continuous thermal control. Spray foam is an air barrier, so convective looping and air leakage thermal losses do not occur. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:22:49Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-8-xps-2x4-framing-with-fiberglass This wall system has an installed insulation R-value of R-23 which is only slightly lower based on the parallel path calculation method which accounts for the wall framing assuming 24” on center. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:26:31Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-9-polyisocyanurate-insulation-2x4-framing-with-cellulose This wall system has an installed insulation R-value of R-25 which is only slightly lower based on the parallel path calculation method which accounts for the wall framing assuming 24” on center. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:28:07Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-10-spray-foam-with-offset-2x4%20framing Open-cell spray foam provides very good continuous thermal control. Spray foam is an air barrier, so convective looping and air leakage thermal losses do not occur. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:32:07Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-11-xps-insulation-on-exterior The advantage of insulating on the exterior is that the insulation on the exterior of the foundation can be joined with the exterior insulation on the first floor, which forms a continuous layer of insulation and vapor control. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:33:27Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-12-xps-insulation-center-of-wall Unlike some of the other wall systems there may be thermal mass benefits of the interior exposed surface of concrete. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:35:19Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-13-insulated-concrete-forms-icf This construction strategy has an installed insulation R-value of R-20. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:42:38Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-14-xps-2x6-framing-with-fiberglass-batt If the rest of the enclosure is super-insulated and airtight, in a very cold climate will it make sense to increase the R-value of the foundation wall. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:44:05Z BSC Article http://www.buildingscience.com/documents/enclosures-that-work/high-r-value-wall-assemblies/high-r-foundation-15-pic-2x6-framing-fiberglass-batt This foundation wall system has a calculated parallel path R-value of R-45 and a yearly heating energy consumption of 11.09 MBTus assuming R-20 under the slab and in the thermal break. No publisher Building Science Corporation doc-InformationSheet guidance-Below-grade enclosure Building America doc-EnclosuresThatWork 2013-04-02T22:45:51Z BSC Article