- 1 When should you use expansion joints in concrete?
- 2 Are concrete expansion joints necessary?
- 3 Where are expansion joints required?
- 4 What can I use for concrete expansion joints?
- 5 What is the difference between expansion joints and control joints?
- 6 How deep do you cut expansion joints in concrete?
- 7 How do you build an expansion joint in concrete?
- 8 Where do you cut expansion joints in concrete?
- 9 What is the distance between expansion joints?
- 10 How do you calculate expansion joints?
- 11 How often should expansion joints be used?
- 12 How do you calculate expansion joints in concrete slabs?
- 13 What is the best expansion joint for concrete?
- 14 Should you caulk driveway expansion joints?
- 15 What is the best concrete joint filler?
When should you use expansion joints in concrete?
Expansion joints are put in place before the concrete is poured. Expansion joints are used to allow the slab to move and not put stress on whatever it abuts. These joint are placed where a slab meets a building, where a slab meets another slab, and where a pool deck meets the coping.
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.
Where are expansion joints required?
Pavement expansion joints are only needed when: The pavement is divided into long panels (60 ft (18 m) or more) without contraction joints in-between. The pavement is constructed while ambient temperatures are below 40F (4C). The contraction joints are allowed to be infiltrated by large incompressible materials.
What can I use for concrete expansion joints?
Sikaflex can be used to seal horizontal expansion joints. It’s a great product because it remains permanently flexible, dries quickly, sticks to anything, is self-leveling, and highly resistant to weather conditions. You should apply Sikaflex when the temperature is between 40F-100F.
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.
How deep do you cut expansion 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.
How do you build an expansion joint in concrete?
When pouring and troweling your concrete slab, use a special trowel called a joint trowel, to create a narrow space between slab sections. This space will allow expansion or contraction, just as a rubber joint would. This method of creating joints is typically used for more narrow concrete surfaces such as sidewalks.
Where do you cut expansion joints in concrete?
A good rule of thumb is to cut the joints one-quarter to one-third the slab thickness. 1 For a 6-inch-thick slab, that means cutting 1.5 to 2 inches deep.
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.
How do you calculate expansion joints?
Tc= Structure temperature during construction of joint opening. L = Length of structure contributing to expansion or contraction of the joint (feet). W = Nominal uncompressed width of expansion seal (inches) A = Joint opening normal to joint at the time of deck placement (inches).
How often should expansion joints be used?
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.
How do you calculate expansion joints in concrete slabs?
The following recommended tips should be observed:
- Maximum Joint Spacing should be 24 to 36 times the thickness of the slab.
- Joints should be spaced about 10 feet and a maximum of 15 feet.
- When using joint groove for contraction joints, the joint should be a minimum depth of ¼ thickness of the slab.
What is the best expansion joint for concrete?
The Reflectix closed cell foam expansion joint is the solution to your concrete placement needs. It is durable, lightweight and flexible enough to shape to contours.
Should you caulk driveway expansion joints?
Caulking Concrete Cracks and Expansion Joints
Even expansion joints in your concrete driveway should be caulked. Notice how the caulking is slightly lower than the concrete slab around it. This protects the caulk from wear and tear of people walking and driving over it.
What is the best concrete joint filler?
Akonaflex™ Expansion Joint Filler is a superior-grade, one-component, urethane sealant and filler to be used in concrete joints as well as a wide variety of substrates.