Isolation/Expansion Joints in Concrete
When building your own home, one of the items that will require your attention during the foundation/flatwork portion of construction is checking the use of expansion joints. Slab-on-grade isolation joints are used where a concrete slab meets another slab or other concrete structure, such as:
- Sidewalks or driveways adjacent to your homes foundation
- Between slabs-on-grade and surrounding foundation walls
- Between slabs and fixtures, such as drains, hydrants, lampposts, columns and other fixed equipment or structures.
- Between garage slab (or trough) and driveways
- Between driveway and sidewalk or roadway
- Between driveway or sidewalk and steps, patio, planter, or similar structure
tooled joint in concrete
Control (Contraction) Joints, Sidewalks and Driveways
Slab-on-ground control joints provide for horizontal movement of adjacent slabs, but do not allow differential vertical movement. Control joints allow for contraction caused by drying shrinkage and eliminate random cracking due to thermal volume changes. Control joints should occur at no more than 5 foot spacing for sidewalks and no more than 15 foot spacing for driveways.
control joint examples
{ 1 comment… read it below or add one }
expansion joints are made out of what is called black board, or celotex, its availbe at most lumber stores,
i would put an expansion joint every 10 ft. and at the step and drive,
use 1/2 inch celotex, put it down pour the cement, add as nessary, and cut control joints every 3 or 4 ft,