Chapter 9

Footings, Foundations, and Concrete

Staking Out?

 Use plot plan to stake out location of the house on the lot.

 Layout corners – 3-4-5 (9-12-15)method – Batter boards – Control point (usually highest point)

Excavation

 Bulldozer or tractor with blade is used to remove topsoil, for fill later.

 Trencher or backhoe used for excavating earth.

 Footings should extend down a minimum of 6” below the average minimum frost depth and 6” into undisturbed soil. (Local code)  Plan for settling.

Footing Shapes

 Increase the supporting capacity of the foundation wall by spreading the load over a larger area.

Footing Shapes and Sizes

Foundation Walls

 Extends from the first floor to the footing  Basement wall or crawlspace  T-Foundation  Slab Foundation  Pier/Post Foundation  (see page 165)

Terminology

 Drain Tile (4” perforated (weep) tile)  Pilasters  Beam Pocket  Gravel Fill  Sand Cushion (between poured floor and footing)  Vapor Barrier  Live Loads – fixed or moving weight not part of structure  Dead Loads – Fixed weights of the structure.

Beams and Girders

 Used to cover large spans, where wood would not be sufficient  S-Beam (I - beam) and Wide flange beam  Lintels – horizontal support over an opening

Concrete and Masonry

 Concrete - Cement, sand, aggregate and water  Cement – Mixture of lime, silica (sand), alumina, iron and gypsum.

 Sold by the cubic yard ~ $30.00/cu.yd.

 Concrete block (cinder block) (p. 179)  Pavers