DRAFT GreenPoint Rated Existing Home Rating Manual version 6.0 | Page 19

B

Foundation

This measure applies to all structural concrete work (poured, block, or shotcrete) within the building (including the foundation, floors, walls, roof, balconies, podium parking garage, etc.), walkways, retaining walls, patios, and driveways. This measure does not include siding/stucco or roof tiles. Note: A structural engineer should provide appropriate calculations for the concrete mix, especially for a 40% mix, to ensure performance. VERIFICATION Documentation: The Rater must obtain a concrete mix receipt clearly stating the percentage of fly ash and/or slag used in the mix. Note: An Accountability Form is not suitable to verify any part of this measure. INTENT To reduce the use of Portland cement. To promote recycling efforts and reduce pressure on landfills.

B3.

RADON-RESISTANT CONSTRUCTION

CRITERIA FOR QUALIFICATION Two points of credit may be given for radon-resistant construction in any radon zone. Construction must be in accordance with EPA best practices for Radon Resistant Construction for New Constructions. For credit, complete all of the following: ? ? ? ? ? ? ? Lay a perforated pipe (with a minimum diameter of four inches) in a four- to six-inch continuous layer of coarse gravel under the foundation slab. Place a layer of continuous, sealed plastic sheeting (6 mm) over the gravel. Connect the horizontal perforated pipe(s) to a solid pipe(s) running vertically to the attic and through the roof for passive sub slab/membrane depressurization. Seal all penetrations or cracks in the slab, foundation, or crawlspace floor with caulk or adhesive sealant. Provide an electrical receptacle in the attic or outside the building for the future installation of a fan (for active depressurization). Test for radon after construction. This test can occur prior to occupancy or after occupancy. The test must be completed by a Certified Tester as identified on the CDPH website. If the test results are greater than 4 picocuries per liter (pCi/L), install a continuously fan for active depressurization.

VERIFICATION Field Verification: The Rater must verify that the building design and specifications include radon-resistant construction materials and techniques at the foundation, frame, and finish stages of construction. If the radon test results are greater than 4 pCi/L, the Rater must verify the installation of the active depressurization system and obtain photos of the continuously operating fan. Documentation: The Rater must collect the following: ? A state or county radon map, with the site location noted 13

GreenPoint Rated Existing Home Rating Manual Version 6.0, September 2013 © Build It Green