1. Foundation Systems

2. Introduction All structures require a foundation
Foundations provide a base to distribute the weight of the building to the soil
Must resist loads from gravity, floods, winds, and earthquakes.

3. Soil Considerations Nature of soil Classification/Names of conditions
Types/Textures
Bearing capacity/Compaction
Classification/Names of conditions
Climate

4. Soil Types Bearing Cap Rock 5000 or 20% crushing value Sand Clay
Course 1500
Fine 1000
Clay
Hard 3000
Sandy 2000
Soft 1000
Adobe 1000
Silt

5. Soil Classifications and Names of Conditions
1--Natural grade
2--Existing grade
3--Finished grade
4--Backfill
5--Compacted Fill
6--Uncompacted Fill
7--Cut

6. Climate Conditions
Frost Depth Chart, see text

7. Climate Considerations
Freezing
Know local conditions
Depth requirement
12” below average frost depth
Follow design rule for sizing footing
width = 2 x foundation thickness
depth = foundation thickness
Water Content
permeability of soil--water absorbed into soil causes expansion

8. Type of Foundations
“Tee” or “T” foundation (Continuous or Spread foundation)
Slab (On-grade) foundation
sometimes called monolithic concrete slab foundation
Pier foundation

9. What the Foundation Looks Like
Like Class Project
Spread and
Slab Foundations
Sectional view
Plan view

10. Tee Foundation W/ Interior Footings

11. What the Pier Foundation Looks Like
Plan view, Exterior or side view, Perspective

12. Special Foundation Conditions
Fireplace Footings, extends 6” beyond
Foundation height out of ground (set by code): 6”-8” above grade, usually 8”
Stepped foundation:
32” horizontal minimum
24” vertical maximum
Anchor bolts: 5/8” x 12” 32” OC
Reinforcing requirements
Rebar sizes given in # of 1/8” diameters. Example #4 = 1/2” Dia.
Range from #2 to #18 diameter

13. Stepped Foundation

14. Reinforcing Bars (Rebar)
Identification Marks:
1--Steel Manuf (Mill)
2--Bar Size(no. of 1/8 dia)
3--Type of steel(grades)
N = new billet steel
I = rail steel
A = axle steel
4--Minimum yield (psi)
40K, 50K, 60K, 75K

15. Foundation Dimensioning
Foundation walls
outside surface/jogs/etc.
Piers/beams
always to center of piers or beams
Vents
dimension to actual opening
Access doors
location and size dimensions req’d

16. Foundation Dimensioning Example

17. Foundation Vents Sizing
1 sq ft ventilation for each 150 sq ft of crawl space area
First, determine crawl space area
Second, Area (x) 1/150 = total net vent sized(TNVS)
TNVS () net area of one vent = # vents required (round up)
(Use product supply literature)

18. Foundation Ventilation
1/150
1/1500

19. Product Supply Literature

20. Crawl Space Access All crawl spaces must have access provided
Type/Location of access
floor to crawl space (possibly in closet or under stairs)
outside access through foundation
Codes vary for size
UBC--18”x30” min
CABO--18” x 24” min
SBC--18” x 24” min
IRC—18” x 24” min

21. Fireplace Construction and Drafting

22. Introduction How many of you have a fireplace in your home?
Is it your major source of heating?
Fireplaces today are more of a luxury item
major element of interior design in living area
provide atmosphere
minor concern for heat

23. Fireplace Design and Construction
Type and style
Structural framing around fireplace
Size & type of opening
Chimney design/height above roof
Fireplace terminology/function
Flue sizing
Fireplace drawings

24. Common Fireplace Types
1--Single faced
flush hearth
raised hearth
2--Double faced
corner designs
3--Double faced
opposite sides design
4--Three faced
5--Free standing

25. Double Faced Fireplace

26. Double Faced Opposite Sides FP

27. Three Faced Fireplace

28. Structural Framing Requirements
No wood or combustible material is allowed to touch any part of the fireplace, its foundation, or chimney
2” clearance usually required by code
No structural piece should rest on the fireplace and use it as support

29. Structural Framing Note double headers & trimmers opening < 10’
ledger strip or Joist hangers
fireplace & chimney free-standing & self-supporting
(from FP below)
(or Joist hangers)

30. Flashing Around Chimney
Drawing callout: 26 GA GI FLASHING
Note
flashing
callout
saddle or “cricket”--diverts water away from behind the chimney

31. Chimney Heights Building Code: (2 foot 10 foot rule)
Chimney 2’ minimum above any construction within 10’ of the chimney

32. Chimney Flues Area through which the combustion gases and smoke travel
Flue liners
used to prevent deterioration to mortar joints
produces a better downdraft & requires smaller flue (smoother surface)
Unlined Flue
Chimney must be thicker walls than with chimney with flues liners

33. Chimney Flues Each fireplace requires a separate flue
may be contained within same chimney
minimum of 4” distance apart
must be different heights, min of 4” from top
4” Min

34. Chimney Cap Spark Arrester keeps water away from lining
stops downdrafts
Spark Arrester
screen device that prevents sparks from leaving the chimney & passing onto the roof

35. Fireplace Terms 1. Firebox--opening 8. Damper--
2. Hearth--min 16” sizes vary
prefered 20” 9. Throat
3. Ash dump Smoke
4. Ash pit chamber
5. Clean out 11. Smoke
6. Steel angle or lintel shelf
7. Mantel 12. Flue
13. Chimney

36. Fireplace Terms/Drafting Layout

37. Fireplace Function Smoke Chamber
1. Transition from the firebox to the flue
2. Responsible for controlling & regulating burning and eliminating smoke & combustion gases
Smoke Shelf
1. Prevent downdraft
2. Help divert cold air into smoke chamber
Throat
1. Channels smoke into chamber
Damper
1. Controls air flow/shut off when not in use

38. Flue Sizing
Crucial that fireplace opening be in proper proportion to flue for proper operation
Inside free space of flue called effective flue area, expressed as fraction
Effective flue area (EFA)
1/10 minimum allowed (10%)
1/8 preferred (12%)

39. Flue Sizing Find affected firebox area based on type of fireplace
Area = h x w
Find affected firebox area
based on type of fireplace
Single faced
Area = h (x) w
Multiply by Ratio
if 30” wide x 26” high
Area = 30 (x) 26 =780 sq in
Effective Flue Area (EFA)
(Considering Min EFA 10%)
Therefore 780/10 = 78 sq in
See tables to select proper flue
Dbl-faced Area = 2(h x w)
Area = 2(w x h) + d x h

40. Flue Shapes, Sizes, and Areas
See Text for a similar table to the table below showing flue lining sizes, etc.
Table relates only designs for 10% EFA, flue areas are okay

41. Flue Sizing find width at bottom find height at left
find intersection
find nearest curve above intersection

42. Fireplace Drawings Required Drawings (see by code or city)
Enlarged Plan view
like the floor plan but to include dimensions to build
Vertical Section
shows all vertical relationships including dimensions
Elevation of Fireplace front view
shows what the fireplaces looks like when finished
Common scales: 3/8” = 1’-0” and 1/2” = 1’-0”
Views are arranges by orthographic projection
height and/or width must align from view to view

43. Fireplace Assignment (w)

44. Fireplace Drafting Layout