A garage floor slab should be planned carefully to avoid cracks. Contractors who install and cure garage floor slabs properly are not worried about the performance of the slabs in any climate or even in the toughest weather conditions.
You can achieve a better concrete garage floor slab by following the below tips.
- Concrete Slab Floor Level
Some contractors would advise you to use a four-inch step rule. The rule states that the floor level of the house should not be the same as that of a garage. The one for the garage should be four inches lower than that of the house.
Today, you can pour a concrete slab to be of the same height as a house slab. The four-inch rule is not among the regulations listed with International Residential Codes.
- Ground Preparation
Ground preparation is very important for any construction project. One of the biggest causes of cracks in the slab is not the weight it carries but the soil beneath.
Sometimes the soil below may shift which may lead to cracks. To avoid this, find out if the soil was once cut and filled. The filled areas should undergo compacting.
A better preparation starts by extracting the topsoil and adding a four-inch membrane of gravel. Compact it well to gain stability for structural support.
- Install Vapor Barrier
Moisture will always be in the ground and can wick up through capillary action. This means without the vapour barrier moisture will move through the porous concrete and condense on the slab floor.
The water moving up will damage any item positioned on the concrete slab. It is recommended that you use manufactured vapour barriers, particularly beneath the concrete slab.
- The Right Concrete Slab Mix
Slab concrete for the garage should be built with a compressive strength between 2500 to 3500 psi. Make the slab at least four-inch-thick, you can make it thicker if the loads that will rest on it are heavy.
There are building codes that provide regulations for concrete mix, although they vary by region. The compressive strength that is expected will be determined by the quantity of water in the mix.
For easy pouring, add more water but be careful as adding more water may lead to a weak slab. You can introduce plasticizers for easy flow of the concrete, this will not compromise the required compressive strength.
In cold regions, it is recommended to use air-entrained agents to the concrete mix. This will protect the slab during freeze-thaw progressions.
You can also insist on fibre reinforcement to increase the strength of the concrete slab.
- Work With Reinforcement
Reinforcement like wire mesh and rebar are components of concrete and provide insurance to the structure. They should exist in the middle of the slab, not at the bottom.
Reinforcement should be properly and adequately secured in the ground so as not to move during concrete pouring.
- Expansion Joints
Concrete expands and shrinks just like wood during temperature and humidity flow. This is why it is advisable to incorporate expansion joints along the edges and around the posts in the slab.
The substance used in expansion joints will absorb any expansion and decrease stress at the same time fills the joints when contraction takes place.
Finishing and Curing Process
When concrete is poured, the next step is to level and smoother it. For additional crack resistance, it is advisable to cut expansion grooves into the wet concrete. Finishing the concrete slab involves spraying little water every day to help it cure smoothly. For a better concrete garage floor, be clear on every step of the construction process with the mix being adjusted accordingly.