Components Footings Trench Formed Keyway Stepped Fireplace
Foundation Concrete support for floor framing & rest of the house
ACCURACY & QUALITY KEY! *Soil quality effects type of foundation used Foundation: Carry Loads Distribute weight to soil evenly Footing spreads the weight Resists forces wind/earth (by anchoring down walls / eaves) Material: Concrete (works in compression) and Steel rebar (works in tension to resist min. earth movement)
Compression is a pushing force Tension is a pulling force
Requirements for footings Rest on Undisturbed soil Lie below the frost line (in colder climates) – Washington Country 12” – Multnomah County 18” – Check your local code Slab on grade used in warmer climates Footing width depends on soil type and # of stories
Soil Bearing Capacity Class of MaterialsLoad Bearing Pressure Crystalline Bedrock12000psf Sedimentary and Foliated rock4000psf Sandy Gravel3000psf Clay, Sandy Clay, Silty Clay,1500psf
Slabs Block Outs and penetrations designated by an X Control Joints - control cracks (every 20’) Expansion joint where vertical wall and slab meet allows for movement due to expansion and contraction.