Can you pour concrete without expansion joints?

Expansion joints are virtually never needed with interior slabs, because the concrete doesn’t expand that much—it never gets that hot. Expansion joints in concrete pavement are also seldom needed, since the contraction joints open enough (from drying shrinkage) to account for temperature expansion.

How big can a concrete slab be without expansion joints UK?

The Need For Expansion Joints There’s aren’t that many driveways that will need expansion joints. A slab can be about 20ft square (6m square) before it will need an expansion joint, but it’s not only size that matters.

Is it too late to cut control joints?

WHEN TO SAW CONTROL JOINTS Cutting freshly poured concrete too late can lead to unwanted cracks in the concrete, rendering the joints ineffective. For most concrete work, cutting should take place within the first 6 to 18 hours and never beyond 24 hours.

What is an isolation joint?

An isolation joint is a separation between adjacent sections of a concrete structure to allow relative movement in three directions and through which all of the bonded reinforcement is interrupted.

What is an isolation joint in concrete?

How Big Should concrete joints be?

Concrete control joints should be no less than ¼ of the total thickness of the slab (1” deep for a 4” thick pour) and placed no less than 2-3 times (in feet) the thickness (in inches) of the slab (8-12 feet apart for a 4” thick pour).

What is the difference between a control joint and an expansion joint?

In building materials, a control joint is used to control cracking while an expansion joint is designed to handle structural movement. A control joint can be formed during placement of the building material or cut after the material is placed.

How deep do you cut control joints in concrete?

Cut joints 25\% of the depth of the slab. A 4″ thick slab should have joints 1″ deep. Groover tools cut joints in fresh concrete. Saw cutting cuts joints as soon as the concrete is hard enough that the edges abutting the cut don’t chip from the saw blade.

What is the difference between an isolation joint and an expansion joint?

Isolation joints separate a concrete slab from something else like a wall, a post, or a pipe. It can also damage pipes and drains. Expansion Joints. While isolation joints are recommended both inside and out, expansion joints are designed primarily for outdoor situations where weather extremes can add to slab movement.