Questions and Answers

Questions and answers about concrete and Cardinal Concrete Ltd. Click each question below to reveal the answer.

What determines how strong concrete will become?

The most important factor influencing the strength of concrete is the amount of water to cement (W/C ratio) in the mixture. The lower this ratio, the stronger the concrete will be. Therefore the easiest way to increase the strength of concrete is to use more cement in the mixture; the easiest way to weaken concrete is to add more water.

 

Can it be too hot or too cold to place new concrete?

Temperature extremes make it difficult to properly cure concrete. On hot days, too much water is lost by evaporation from newly placed concrete. If the temperature drops too close to freezing, hydration slows to nearly a standstill. Under these conditions, concrete ceases to gain strength and other desirable properties. In general, the temperature of new concrete should not be allowed to fall below 10˚ Celsius during the curing period.

For further information on this topic download our Cold Weather Concrete Tips sheet

 

What kind of joints should be used in concrete paving (such as a driveway)?

The most common joints used in concrete paving are called ‘control joints’. These are to accommodate the shrinkage that is normal in concrete. ‘Isolation joints’ may also be required to separate the paving from posts, drains, or adjacent walls.

 

How thick does a concrete driveway need to be?

Throughout North America it is conventional to form residential driveways with 2″x4″ lumber. This results in a pavement thickness of approximately 3.5 inches or 90mm. This thickness is adequate for cars, pick-ups and SUVs. If heavier commercial vehicles will use the driveway more frequently then a greater thickness of concrete is needed.

 

Why should I use concrete for my driveway if I can get asphalt more cheaply?

Begin by considering the cost of the driveway over its lifetime. A good quality concrete driveway will last more than 30 years with little or no maintenance. Asphalt driveways need periodic sealing coats to slow age related cracking. Even properly constructed residential asphalt driveways will deteriorate more quickly due to environmental influences than due to vehicle traffic. If you consider the cost of surface and crack sealers and the shorter life-span of the asphalt, concrete will cost much less.

If you’d like to learn more and get a price estimate for your concrete driveway, please call 604.898.5015.

 

What does it mean to “cure” concrete?

Curing is one of the most important steps in concrete construction, because proper curing greatly increases concrete strength and durability. Concrete hardens as a result of hydration: the chemical reaction between cement and water. However, hydration occurs only if water is available and if the concrete’s temperature stays within a suitable range. During the curing period – from five to seven days after placement for conventional concrete – the concrete surface needs to be kept moist to permit the hydration process. New concrete can be wet with soaking hoses, sprinklers or covered with wet burlap, or can be coated with commercially available curing compounds, which seal in moisture.

 

Why does concrete crack?

Concrete, like all other materials, will slightly change in volume when it dries out. In typical concrete this change amounts to about 500 millionths. Translated into dimensions-this is about 1/16 of an inch in 10 feet (.4 cm in 3 meters). The reason that contractors put joints in concrete pavements and floors is to allow the concrete to crack in a neat, straight line at the joint when the volume of the concrete changes due to shrinkage.

 

Are you open on Saturdays?

Yes, Cardinal Concrete is open on Saturdays by request. Please contact our Dispatch office at 604.898.6000 to schedule your pour.

 

How far can the pump reach?

The boom pump can reach up to 120 feet.

 

How much does the pump truck cost?

Please contact Westland Concrete Pumping, at 604.898.6000, for current pricing information.

 

Can you recommend a contractor or concrete finisher?

We can provide contact information for several local concrete finishers. We recommend that you contact a few to get quotes and references before making your selection.

 

How much does the concrete weigh?

Concrete weighs 150lbs per cubic foot.

 

Do you have the small trucks to get in my back yard?

Unfortunately we do not operate small concrete trucks. However, we can arrange a concrete pump for your job, if the pour is in a difficult to reach area.

 

Is the concrete going to be dark or light coloured?

The colour of the placed and cured concrete will vary based on the supplier of the cement powder.

 

How thick should the concrete be poured?

Generally, you should pour the concrete at least 4 inches thick. However, there are sometimes other circumstances and your concrete installer can calculate the depth and amount of concrete you will need.

 

How much concrete do I need?

This calculation is based on the size of your area, and type of job you are doing. The company installing the concrete will budget that for you with your forming. You can also use our volume calculator to get an approximate volume of concrete.

Does Cardinal Concrete do the concrete installation?

No, we are the material supplier only.  You will need to contact a contractor or concrete finishing company to form and place your concrete.