Category Archives: Concrete

The Effect of Deicers on Concrete

The Effect of Deicers on Concrete

You’ve probably heard lots of advice on what deicers are safe to use and which aren’t on concrete surfaces.  The frustrating part comes when that advice is confusing, contradictory or generally based more on something people have heard rather than hard evidence.  That’s where science comes to the rescue!

Researchers at the University of Kansas sought to answer this question once and for all in a recent study on the effects of deicers on concrete deterioration.  They exposed samples of concrete to four of the most common deicing agents – sodium chloride, calcium chloride, magnesium chloride and calcium magnesium acetate.  The study ran for 95 weeks, with regular cycles of wetting and drying.

As a general rule, they found that sodium chloride was the safest deicing substance.  Significant quantities of any of the other three will impact the long-term durability of your concrete.  That’s not to say they all affected it in the same way, but sodium chloride was the clear overall winner.

At low concentrations, calcium chloride had a relatively small negative impact, just like regular old sodium chloride.  That’s more damage than the control concrete suffered, but nothing too drastic.  The other two, however, caused measurable damage, even at low concentrations.

When the concentrations were cranked up, the results got worse.  Even sodium chloride caused measurable damage, highlighting the danger of over-deicing your surfaces.  The other three, however, were much, much more harmful – creating significant changes in concrete that result in loss of material and reduced stiffness and strength.

In short?  Stick with rock salt for your new concrete surface when possible.  It’s not as fast as some of the other alternatives, but it will cause the least problems for your concrete over time.  If you must use something stronger for extremely harsh conditions, calcium chloride is your next best bet.  Avoid magnesium, and definitely avoid ammonium – ammonium based deicers chemically damage your concrete.  As always, use caution and common sense, and your concrete will likely be just fine.

concrete

Guide to Maintaining a Concrete Driveway

One of the best features of a concrete driveway is the lack of regular routine care – it’s a strong, durable surface that can withstand a great deal of punishment.  That doesn’t mean that it’s entirely maintenance free, however – proper preventative maintenance can seriously extend the life of your surface and make sure your investment lasts as long as possible.  Here are our top tips:

Reapply Sealer As Needed

Keeping your driveway sealed prevents water from entering the surface, which can be a source of cracking and other damage in Ontario’s harsh freeze-thaw cycles.  There is no magic number for how often you should reseal your concrete; it will depend on the weather conditions it’s exposed to and the amount of traffic it receives.  As a general rule of thumb, resealing it every two years is a good plan.

Remove Stains Immediately

Concrete sealer does help prevent stains from being absorbed, but that doesn’t mean it’s impervious to stains.  Don’t let oil, gasoline or grease stains sit on your concrete; it will discolor it and ruin the aesthetic appeal.  If it does discolor, pressure washing is often enough to remove the stains, though there are also chemical cleaners you can buy if that doesn’t do the trick.

Avoid Deicing Chemicals

A recent study showed that using deicers containing ammonium nitrates and ammonium sulphates attack your concrete on a chemical level, in addition to the scaling and spalling caused by forcing moisture to thaw and refreeze.  Rock salt or calcium chloride is less harmful to your concrete, though they can harm vegetation and metal.  In general, try to deice as little as possible, especially in the first year of your concrete’s lifecycle.

A Little Care Goes A Long Way

It may be concrete, but it’s not impervious.  Residential driveways aren’t designed to handle, for example, large construction equipment or fully loaded moving trucks.  Use your new surface wisely and avoid subjecting it to excessive strains and loads, and your concrete will continue to look good for years to come.

Why is my Concrete Cracking

Why is my Concrete Cracking?

All driveways will eventually age and crack as the materials age and break down – but that’s something you should be dealing with in 15 or 20 years, not in the first few years after installation!

So, what is causing those cracks?  Here are a few of the most common sources of concrete or asphalt cracking – and how you can avoid them.

Freeze/Thaw Cycle

The single biggest source of cracks in the Toronto area is the freeze/thaw cycle.  Melted snow will seep into the pores in your concrete.  When it freezes again, it expands – and that causes the damage and cracking.  Salting your driveway only makes things worse; it gets into your surface and then attracts water, lowering its freezing point, and making more freeze/thaw problems.  Avoid using rock salt, and instead use calcium chloride – that lowers the freezing point far enough that those freeze/thaw cycles will be less common.  Sealing your concrete will help prevent the salt and water from penetrating in the first place, helping preserve your surface.

Heavy Loads

We may think of concrete or asphalt as indestructible, but in reality, it’s like any other surface.  If you had a parking lot made of glass, you’d expect heavy loads to crack it.  The same is true for concrete; we’re just talking much, much larger loads.  Vehicles weighing north of 5,000 kg can end up doing serious damage to your surface – and those cracks can be entry points for water for future damage.  If you’re expecting particularly heavy vehicles, you’ll need more heavy-duty concrete or other materials to withstand the load.

Sharp Objects

Those studded winter tires?  Snowblower blades?  Even the scraping of a snow shovel?  They can easily chip or crack concrete driveways.  If you must use metal, be very careful – and, when possible, use plastic shovels and tools.  They’ll chip before your driveway will!

How to Handle an Old Concrete Driveway

How to Handle an Old Concrete Driveway

After a while, even the best-laid concrete driveways will begin to show their age.  From discolorations to cracks, you’ll eventually lose the luster and yard appeal a brand new driveway can give you.  But what should you do with an old concrete driveway?  There are several options to choose from, depending on your specific needs and situation.

Repair

Your driveway may simply need to be resurfaced.  If it’s experiencing cracking, scaling or spalling – but not severe damage to the subbase – resurfacing can help restore your concrete to a nearly new state.  Resurfacing doesn’t just cover up the existing flaws in your concrete; it can help you create a brand new look with a variety of patterns and colors of stamped concrete.

If your underlying concrete is still structurally sound, concrete resurfacing can be a way to give it a facelift, restoring it to its original beauty and repairing the superficial damage that use and weather can cause.  Epic Paving and Contracting offers professional repair and resurfacing for cracks in concrete.  We seal cracks, repair patches, and much more.    You can contact us for a consultation, and we can examine your driveway and discern whether resurfacing is right for you.

Replacement

Not all concrete damage can be fixed with a resurfacing.  If you have widespread, deep cracks where settlement has occurred, or sunken concrete, any repair work will be temporary – and probably too temporary to really justify the time and expense.  In these cases, replacement makes much more sense.  This involves removing the concrete and sub grade entirely and starting from scratch.

From there, of course, you have options – you could replace it with a new concrete driveway, or opt for a different material such as asphalt.  If you’re planning on replacing a concrete driveway with asphalt, it’s best to remove the entire concrete driveway anyway due to the differing requirements in the subbase.  Either way, you don’t want to do a quick patch job that won’t hold up – if the damage becomes too severe, it’s time to replace with something long-lasting and well-designed.  Epic Paving can help ensure your new driveway will stand the test of time.