1. FOUNDATIONS

2. Components Footings Trench Formed Keyway Stepped Fireplace

3. Foundation Concrete support for floor framing & rest of the house

4. 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)

5. Compression is a pushing force Tension is a pulling force

7. 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

8. Soil Bearing Capacity Class of MaterialsLoad Bearing Pressure Crystalline Bedrock12000psf Sedimentary and Foliated rock4000psf Sandy Gravel3000psf Clay, Sandy Clay, Silty Clay,1500psf

9. Footing Widths Examples: Soil bearing capacity 1000 psf +1 story= 18” Footing Soil bearing capacity 3000 psf +1 story= 12” Soil bearing capacity 1000 psf +3 story= 27” Soil bearing capacity 3000 psf +3 story= 12”

10. Footing Widths LOAD BEARING VALUE OF SOIL (psf) 1000150020003000 Conventional Light-Frame Construction 1-Story1812 2-Story231512 3-Story27181412 4” brick veneer over light frame or 8” hollow concrete masonry 1-Story231512 2-Story29191312 3-Story35231612 8” solid concrete or masonry, or fully grouted masonry 1-Story26171312 2-Story36231812 3-Story45302316

11. More Footing Requirements Horizontal Rebar per local code Vertical Rebar per local code Must project at least 2” beyond wall A means of connection to wall – Keyway – Rebar

12. KEYWAY

13. Types of Footings

14. STEP FOOTINGS

15. 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.

19. Reinforcing Bar (Rebar) Measured in 8ths – Example: #4 Rebar = 4/8 or ½” diameter #3 rebar = 3/8” diameter

20. 3 Types of Residential Foundations 1.Crawl space 2.Basement (full or partial) 3.Slab on Grade Alternative FND. Pole / Pilings (when soil not good)

21. Crawl Space 18” minimum height from ground to bottom of floor joist

22. Crawl Space

23. Basement Wall

24. Stem Wall

25. Slab On Grade

27. Abbreviations & Terms WWM = welded wire mesh WWF = welded wire fabric

28. Step Footing

29. YOUR TURN