County approved permit plans are required on site for all inspections including reinspections.
This SLAB inspection is required before placing concrete.
- The slab area shall have all vegetation, topsoil and foreign material removed. Fill material shall also be free of vegetation and foreign material.
- Forms shall be in place for combination slab and footing (monolithic) pour. Note: The 6″ – 10″ slope required away from the foundation may affect the proposed slab height. A 6″ clearance will be required to the bottom of the siding and/or an 8″ clearance to the sill plate to comply with the decay resistant materials section of the code.
- Fill shall be compacted to assure uniform slab support. The depth of clean sand or gravel fill shall not exceed 24 inches, or, if earth fill is used, earth depth shall not exceed 8 inches. Fill in excess of the amounts listed above will require certification by a registered design professional.
- An approved vapor barrier, minimum 6 mil (usually polyethylene) shall be placed wall to wall in heated accessory structures and houses built on slab with any seams to be lapped a min 6″.
- Sill plate anchorage is required. There shall be a minimum 2 bolts per plate section with one bolt located no more than 12 inches or less than seven bolt diameters from each end of the plate section. Additionally bolts are required within 12″ of each corner and at a maximum on center spacing of 6 feet around the full perimeter. Bolts are to be a minimum 1/2″ diameter x of sufficient length to provide a minimum 7 in. embedment with enough projection above the slab to penetrate completely through the plate and to receive a washer and nut on the bolts without having to mortise the plate. Straps are to be installed as per the manufacturer’s specifications and shall be spaced in accordance with the manufacturer’s installation instructions.
- If the slab is less than 12″ below grade, the perimeter of the slab shall be insulated with 20″ wide insulating sheets placed on top of the vapor barrier. Additionally, a 4″ wide strip of insulating sheet shall be placed around the perimeter to isolate the slab from the exterior. The “R” value for this insulating sheeting shall be 10 or greater. Slab insulation is required for any portion of the slab, with a top edge 12 inches or less below finished grade.