- 1 When Should expansion joints be cut in concrete?
- 2 How big can a concrete slab be without expansion joints?
- 3 Is it too late to cut control joints?
- 4 How do you cut a concrete groove?
- 5 Are concrete expansion joints necessary?
- 6 What material is used for expansion joints in concrete?
- 7 What is the difference between expansion joints and control joints?
- 8 What is the distance between expansion joints?
- 9 Do you need expansion joints in a garage floor?
- 10 How deep should you cut concrete?
- 11 What do you use to cut concrete?
- 12 Why do they cut lines in concrete?
- 13 What kind of blade Do I need to cut concrete?
- 14 How much slope is needed for a concrete slab?
When Should expansion joints be cut in concrete?
Joints should be sawed as soon as the concrete will withstand the energy of sawing without raveling or dislodging aggregate particles. For most concrete mixtures, this means sawing should be completed within the first six to 18 hours and never delayed more than 24 hours.
How big can a concrete slab be without expansion joints?
Usually, expansion joints should be no farther apart than 2 to 3 times (in feet) the total width of the concrete (in inches). So for a 4 inch thick concrete slab, expansion joints should be no more than 8 to 12 feet apart.
Is it too late to cut control joints?
Sawing too late can result in uncontrolled cracking as the concrete contracts during curing. Do not twist the blade, do not let the blade spin. If the saw cuts are made too soon, the joint edges may ravel. For most concrete work, cutting should take place within the first 6 to 18 hours and never beyond 24 hours.
How do you cut a concrete groove?
If you need to cut a shallow channel into a concrete floor to accommodate plumbing, electrical or another purpose, the quickest and easiest way is with a diamond-blade wet concrete/asphalt saw, which you can rent from many tool rental centers.
Are concrete expansion joints necessary?
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.
What material is used for expansion joints in concrete?
Minimize Concrete Cracking and Damage with Expansion Joints. ASPHALT EXPANSION JOINT is composed of a blend of asphalts, vegetable fibers, and mineral fillers formed under heat and pressure between two asphalt-saturated liners. It is waterproof, permanent, flexible, and self-sealing.
What is the difference between expansion joints and control joints?
A control joint is a continuous vertical joint filled with mortar, but with a bond breaker on one side so that tensile stress cannot develop across the joint. An expansion joint is a continuous vertical or horizontal joint, left completely free of mortar and filled with elastomeric sealant to keep it watertight.
What is the distance between expansion joints?
1. In brick or stone masonry expansion joints normally need not be necessary, except in the case of long walls exceeding 30 m in length; in such long walls the expansion joints shall be not less than 15 mm wide and shall be spaced not more than 30 m apart.
Do you need expansion joints in a garage floor?
Many people understand that wood shrinks and expands as temperature and humidity ebb and flow through the year. But the same thing happens with concrete. That’s why it is necessary to include expansion joints along the edges of the concrete garage floor as well as around posts or other protrusions in the slab.
How deep should you cut concrete?
As far as the depth of the cut is concerned, professionals recommend cuts ranging from one quarter to one third of the thickness of the slab. Simply put, this means that the cutting depth should be restricted to around 2.5 inches for an 8 inch thick concrete slab.
What do you use to cut concrete?
Any handy homeowner looking to cut concrete needs one crucial tool: a diamond blade. While abrasive blades can cut concrete, they wear out quickly, potentially needing to be replaced multiple times in the course of one project.
Why do they cut lines in concrete?
To prevent sidewalks from cracking in random spots and breaking apart, builders make lines in sidewalks. The technical term for sidewalk lines is contraction joints. Contraction joints are placed in fresh concrete before the concrete dries and has a chance to create its own joints, which we call cracks.
What kind of blade Do I need to cut concrete?
Use a standard circular saw, equipped with a corundum or diamond blade, for small tasks. For slabs, it’s best to cut through the top inch, then use a sledgehammer to break off the rest. The jagged edge left below the cutting line provides a good rough edge for the new concrete to bond to.
How much slope is needed for a concrete slab?
The standard slope for proper concrete drainage is a one-quarter inch drop for every foot of length. So, to calculate the difference in height between one end of a patio or walkway and another, simply multiply the length by one-quarter.