7818 LARIMER RD B Geotech Report 2022-10-25

E Placement and curing conditions will have a strong impact on the final concrete slab integrity. Floor slabs should be adequately reinforced. • The need for a vapor barrier will depend on the sensitivity of floor coverings to moisture. If moisture sensitive floor coverings are proposed for portions of the proposed structure, a capillary break material, typically consisting of a "clean" gravel, should be considered. We can provide additional recommendations if this is the case. • Provided gravel is desired below the slab, a layer of 4 to 6 inches can be used. Plumbing passing through slabs should be isolated from the slabs and provided with flexible connections to allow for movement. Under slab plumbing should be avoided if possible and should be brought above the slab as soon as possible. • Where mechanical equipment and HVAC equipment are supported on slabs, we recommend provision of a flexible connection between the furnace and ductwork with a minimum of 1.5 inches of vertical movement. • Sidewalks and other exterior flatwork should be separated from the slab and the slab should be designed as an independent unit. STRUCTURAL FLOOR & CRAWL SPACE Structural floors should not be constructed without a geotechnical design for the site after site grading plans and project design is completed and made available for our review. If structural floor is used, then the grade beams (if used) and floor system should be physically isolated from the underlying materials with crawl -space type construction. The void or crawl space of minimum of 6 inches or whatever is the minimum current International Building Code (UBC) requirement. For crawl -space construction, various items should be considered in the design and construction that are beyond the scope of geotechnical scope of work for this project and require specialized expertise. Some of these include design considerations associated with clearance, ventilation, insulation, standard construction practice, and local building codes. If not properly drained and constructed, there is the potential for moisture to develop in crawl -spaces through transpiration of the moisture/groundwater within native soils underlying the structure, water intrusion from snowmelt and precipitation, and surface runoff or infiltration of water through irrigation of lawns and landscaping. In crawl space, excessive moisture or sustained elevated humidity can increase the potential for mold to develop on organic building materials. A qualified professional engineer in building systems should address moisture and humidity issues. Proposed Construction Project No: 0470-WA18 January 24, 2019 Page No: 9 of 17