Necessary guide to floor slab construction

Customary mistakes can be avoided in concrete floor slab construction if proper placement, curing, base preparation, finishing, and mix design is performed. If these steps are correctly performed, then the owner without hesitation can expect a durable and attractive product. Normally the standard thickness of floor slab construction is around 4 inches in residential construction. Though if the concrete is assumed to receive occasional hefty loads like garbage trucks or motor homes then the thickness is recommended to be around five to six inches. 

Preparation for the floor slab construction

For the preparation of the base, the ground level is cut into such depth that the slab thickness would be allowed. All the organic materials and huge solid objects such as tree roots and stones are removed. It is recommended that they should be removed to a depth of at least around 4 inches. Sandy soil or even gravel is used if the necessity of building up the grade is observed. Then the final base is compacted with a plate whose main function is to vibrate. Sometimes a similar device is also used in place of a vibratory plate. The edge form is recommended to form from any straight material. One should use grade stakes and set a string line to make a perfect square.

Design being mixed

One should always pay attention when a concrete mix is concerned. It must meet the requirements of compressive strength which are somewhere around 3000 pounds per square inch. Without testing and measuring it, it would lead to extra shrinkage. Experts suggest that plasticizer should be preferred over water as water causes cracking and an increase in shrinkage. Plasticizer plays a vital role in achieving the intended slump. Sometimes due to slabs being exposed to freezing weather higher strength air may be used.

It is recommended by the experts that in floor slab construction one should avoid adding excess water. If there is truly a need for extra slump then one should always prefer to ask from the mixer truck driver that how much water should be added.


Curing condition is very censorious and the method of curing should start as soon as the surface is ready to resist damage. One thing to be careful about is that, the concrete should not be given time to dry out or freeze. Curing compounds can be placed above the surface. Many times there is a chance of freezing, so to prevent it from freezing one should cover it with an insulator. An insulator is placed until unless the slab is able to attain strength of minimum 500psi. This process of floor slab construction normally takes a few days.

Wrapping things up

After this, the concrete should be distributed around the slab which should be near to its final position. Then it should be gathered into position. Then one should integrate slump mixes which are low with a handheld vibrator. It should be finished by applying the minimum force possible. After this, here comes the main part of floor slab construction. Control joints should be created and one should focus that it should not be more than 24-30 times the thickness of the slab. Meanwhile one should also note that it should not be greater than 15 feet when width and length is concerned.

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