Foundation Systems

1
Foundation Systems
2
Standard

• ACT-ADDI-6 Students will prepare foundation
  plans.
• Explain the purpose of foundation plans.
• Identify different foundation systems and
  terminology.
• Draw and dimension foundation plans.

3
Purpose

• To provide a base to distribute the weight of the
  structure onto the soil
• It must be evenly distributed over a large enough
  area to prevent compression of the soil
• Must resist floods, winds, and earthquakes
• Floods can wash away supporting soil
• Wind pushes against houses, pushing them up
• Must move with the ground in an earthquake

4
Soil Considerations

• Bearing capacity of soil must be known before
  foundation can be designed
• Bearing capacity amount of weight a square foot
  of soil can support
• Freezing foundation should be built below
  freezing level
• In Georgia under 10
• In Minnesota up to 100!
• Water content soil will expand and contract
  with water

5
Types of Foundations

• Pilings
• Continuous (Spread) Foundations
• Grade Beam

6
Piling Foundation System

• Uses beams placed between vertical supports
  (piling) to support structural loads
• When structural load exceeds bearing capacity of
  soil
• Used on steep hillsides
• Site subject to flooding

7
Continuous Foundation

• Most common in residential construction
• Consists of a footing and wall
• Footing base of the foundation system made of
  poured concrete
• Footing can be bonded to the foundation wall with
  a key or with steel

8
Grade Beam Foundation

• Provides added support
• Grade beam is placed under the soil below the
  stem wall and spans between stable supports

9
Fireplace Footing

• Masonry fireplace will need to be supported by a
  footing
• 12 deep footing that extends 6 past the
  fireplace on each side

10
Veneer Footings

• An extension of the footing and must be wide
  enough to provide support for the veneer

11
Foundation Wall

• Vertical wall that extends from the footing to
  the first floor
• Centered on the footing to help evenly spread the
  load
• Height of the wall must extend 6 above the
  ground

12
Retaining/Basement Wall

• Walls that extend full height between the
  basement floor and main floor level
• Basement walls made of poured concrete or
  concrete blocks (or wood, depending on the
  building trends of your area)
• Used on sloped lots

13
Interior Supports

• Spot footings also known as piers match the
  depth of footings

14
Pedestals

• A column built on top of a footing
• Used when upper soils are unstable

15
Metal Connectors

• Used to anchor the house to the foundation

16
On Grade Foundations

• Slab