Building Regulations for Raising a Garage Floor

Floor Problems

• Raising a garage floor is typically necessary only because of damage to the floor caused by shifting soil or foundational problems. It is this damage that violates the building regulations by allowing a weak foundation, areas where moisture can enter the home and general structure or stress-bearing problems. Raising the garage floor restores the garage to its original form, meeting necessary safety codes and preventing any further damage. The floor-raising process must be completed properly by a professional in order to maintain necessary stability.

Drilling

• The first step of the slab jacking process is drilling holes throughout the tilted or broken concrete slab. The holes must be larger than 1 inch in diameter but not larger than 2 inches, providing a range for contractors to work within based on the amount of damage and the type of floor. At least several holes should be drilled in the slab to provide multiple access points, but no holes are drilled closer than 1 foot away from any surrounding walls. The thicker the slab is, the closer the holes are drilled to one another.

Grout

• When the holes are formed, a grout mix is pumped underneath the slab to lift it back up to a level position. The type of grout is very important. Too weak, and the mix could cause the slab to fail again, but the grout needs to be fluid enough to be properly pumped. Cement limestone mixtures are used, as are cheaper cement and fly ash combinations, with a ratio of 1 part cement to 3 parts limestone or ash. Plasticizers, synthetic liquids made with plastic compounds, are sometimes used to ensure greater strength. Plasticizers do not evaporate the way water does, and can encourage stronger bonds between concrete particles.

Repairs

• The last step in the slab jacking process is the repair to the drilled holes. These holes are patched with a different mortar mixture designed to provide greater stiffness and blend in more easily with the slab itself. If the holes were cored, the cores can be glued back in for better results. If the project was a success, the slab will then be level and sound once more.