Restoration and Protection

Basement Floor Cracks
Prevention &  Repair

Cracks in floors (and walls) are a very common occurrence.  Not only does it crack, it wants to crack.

Even before the concrete is poured, the ground under the new slab needs to be prepared properly.  As a contractor I have been called in to pour concrete and refused to do so when the base is uneven and un-compacted.  In the haste to get the floor down, preparation is sacrificed.  This is a critical step in achieving a successful outcome.

Secondly you must place a vapour barrier under the slab to prevent moisture transfer and radon gas infiltration (a problem in some areas).  If you want a warm basement floor, include styrofoam under the slab.  Radiant floor heating pipe (Pex) can be installed at this time to provide for the best basement heating system available.  Even if you just do the "rough in", and add the boiler later, you can enroll the cost into the construction loan or mortgage (smart!).

As concrete makes the transformation from a plastic state to a solid slab, it shrinks slightly. In fact, concrete slabs can shrink one-sixteenth of an inch for every 10 linear feet of distance. The shrinkage is even more when excessive water is added to the mix to make it easier to spread.  This shrinkage creates tension within the slab.

Stress builds up within the recently poured concrete slab. As soon as these forces exceed the strength of the concrete, the slab cracks. Cracks can appear within hours to 30 days of the concrete pour.

Concrete is very strong when you compress it, but it typically only has one-tenth the strength when tension pulls it apart.

There are ways to minimize cracks in concrete floors.

Saw cuts or formed grooves can encourage concrete to crack along a predetermined line.  As we all know, this doesn't always work as well as we want it to.  Joint layouts are a science in the the concrete world.  Once a joint layout is determined and installed in the slab, you can caulk the joints if you like with a good polyurethane caulk.  Exterior slab joints (driveways, patios) should always be caulked as water can penetrate joints and cause deterioration over time from freezing.

Steel mesh (6"x6") or reinforcing bars and /or small plastic fibres can be added to the concrete slab. While these materials can't ensure a crack-free slab, they will hold the concrete together enough so that small harmless hairline cracks occur instead of ones one-eighth inch or more. (Note: steel will rust and destroy or discolour concrete if it is used in exterior or wet locations without proper construction techniques.)

The bars should be placed in a grid pattern with the bars on
24" centers in both directions. In addition, the concrete can be ordered with special fibres that will help prevent shrinkage and tension cracks.

In addition, quality concrete mixes from reputable ready mixed concrete companies can be designed to significantly reduce cracking through the use of chemical admixtures.

Floor Crack Repair

How we do it

There are a couple of ways we can fix cracks in floors (and walls).  The first method is to route out the crack using a diamond routing blade in an electric grinder, clean the resulting groove then apply a bond breaker to the bottom of the groove before installing the caulking sealant.  Usually we will use a high quality one component polyurethane sealant.  Cracks that can be saw cut allow for the installation of a foam rope (backer rod).

This method will provide a good seal to the crack and will allow for some limited movement to occur.  Large movements will rupture the seal.  Good for basement floors, pool decks, patios and driveways.  Colour matching is usually not a problem, as there are plenty to choose from.  Exterior caulking can last up to ten years if installed properly but should be redone as needed.

Surface Repairs

A wide variety of packaged products designed for special applications allow us to restore worn or damaged surfaces to better than new.

Porch and patio coatings.

Garage floor rehab.
 

 

 

Paint stripping and cleaning by
High Pressure water/sand Blast  

 

 

Light masonry restoration, chimney's and porches.

               

                     

Parging repair.

 

Of course, we can fix and repair just about any concrete structure out there, so just give us a call about your project.  705-728-3476 or send an email.