Frequently Asked Questions
Below are some frequently asked questions with their answers for your convenience.
Jump to: Service Questions - Concrete Questions - Concrete Care - Sealers
Service Questions
Do you go to all areas?
Yes! We've done work from Yanchep to Beverley to Armadale and all over the Perth metro area.
How long will it take?
Most jobs are completed in one day including earthworks to the removal of formwork. Complicated, difficult access and jobs greater than 50m2 may take two or more days.
Line cutting and concrete honing are done on another day after the concrete has time to harden.
Exposed aggregate takes at least two days as we will return the following morning to remove the top layer of cement to exposed the stones.
Sealing is usually done several weeks later as prescribed by the sealers instructions.
Do you do all colours?
Yes! All colours are available, as well as a variety of decorative stones for use in exposed aggregate and honed concrete. You can visit our Resources page to get an idea for what colours and coloured stones are available or give us a call to discuss your needs.
Can you match my existing concrete?
Absolutely! We can match the style and colour of your existing concrete. However, coloured concrete can vary mix to mix, depending on the materials and pigments used but we should be able to get close. Also note that the colour won't be exactly the same, even two separate concrete loads from the same concrete plant on the same day can differ slightly.
How much does concrete cost?
The price of concrete varies depending on different factors, so we cannot give a fixed rate for our services. However, we are happy to provide you with a free no obligation quote.
How do I pay?
Payments can be made by cash, cheque, direct deposit bank transfer and credit card (Visa, Mastercard and American Express accepted, a 1.9% fee may apply)
Concrete Questions
Does coloured concrete fade?
The colour pigments used in coloured concrete are UV stable and fade resistant and does not fade. The cement does however change tones during the curing process and as it ages in the weather. This may be due to efflorescence and is explained in more detail below in "Why is my concrete turning white".
Will my concrete crack?
Unfortunately all concrete cracks. This is due to a number of reasons, such as the concrete and surrounding surfaces expanding and contracting, ground movement, heavy vehicles and tree roots. We reduce the appearance of cracks using the following methods.
Contraction Joints are lines in the concrete made by using saw cuts or a grooving tool and are designed to create weak spots in the concrete where cracks are likely to occur, so that they are less noticeable.
Expansion Joints is adhesive foam installed on walls and adjacent concrete to allow for the expansion of concrete.
Steel mesh reinforcement increases the strength of concrete and prevents the cracks from widening and separating. It keeps the concrete locked tightly together and prevents weeds or ants from invading the cracks.
Why is my concrete turning white?
Whilst concrete is curing and the water evaporates from the concrete excess lime from the cement rises to the surface. This results in the formation of salts on the surface of the concrete as the lime reacts with the air resulting in a chaulky white coloured film. This is called efflorescence. This is normal and will naturally fade naturally over time with rain and general wear and tear. This film can be removed to darken and bring out the colour of the concrete. See the next question for removing efflorescence.
Concrete Care
How do I remove efflorescence?
There are several ways to remove efflorescence. The best and safest way is to use an efflorescence remover available from hardwares such as bunnings and follow the instructions on the product.
You can also use hydrochloric acid mixed with 10 parts water to 1 part acid, however always test in an inconspicuous area first to determine if it has the effect you desire. Apply to dry concrete with a watering can or sprayer and then be sure to wash off the acid with plenty of water or neutralize with a baking soda solution as leaving acid on can have undesirable effects.
Work your way up from the bottom of any slopes to avoid acid running down the hill over dry concrete, which can leave a mark. Make sure to read the labels for your safety.
How long before I can use the concrete?
Generally you can walk on the concrete the next day and drive a car on it two days after being laid in summer. In winter when it's cold wait two days to walk on and four days to drive on your new concrete. Trucks and heavy equipment should wait 28 days for the concrete to reach its full strength before use.
Should I water the concrete?
Yes, if you can keep it continuously wet. Assisting the curing of concrete by keeping it moist will make it stronger. If you can keep your concrete continuously wet for 3 days, you can increase the strength of your concrete by up to 50%. Or if you can keep it wet for 28 days it can make it 130% stronger! This will make it less likely to crack and be more durable.
Putting cold water on hot concrete may induce cracking. Be aware that thermal shock may occur if you put cold water on hot concrete.
Allowing the concrete to dry between each wetting may increase the chance of cracking. As the concrete gets wet and dry it expands and contracts which can induce cracks to form. Therefore, from the next morning after placing, keep it wet for as long as you can without it drying out, but if it does dry out, in order to not provoke cracking it may be best to let it stay dry.
You can try "ponding" the concrete or using sprinklers on timers to assist with keeping the concrete wet. You can also consider covering the concrete with plastic or fabric to reduce the evaporation of moisture from the concrete.
There are also concrete curing membranes you can apply to fresh concrete which will help lock in moisture which in turn should make the concrete stronger. Always read and follow the instructions for these products.
Note: Watering the concrete can increase efflorescence and we have even seen it turn the concrete green!
Sealers
How long before I can seal concrete?
When using sealer it's best to read the label completely and follow their instructions on how long to wait and how to apply. Each brand of sealer has it's own waiting period and requirements. Generally you have to wait from 14 days to 28 days after pouring the concrete before a sealer can be applied. Sealing too early can bring about various problems including the concrete turning white under the sealer or delamination of the sealer itself.
Note: Be wary of verbal advice from contractors, sales men or strangers as what is written on the can is what you should follow.
Which sealer should I use?
Our current recommendations are Crommelin's Water Based Paving Sealer available at Bunnings and Nutech Pavecoat sealers available at Westflex in Maddington.
More sealer information please.
There are no rules as to which sealer to use (except for Liquid Limestone which requires a sealer that allows it to "breathe"). Consider when choosing your sealer which attributes you need, such as appearance, stain resistance, ease of application, slip-resistance, cost and VOC content (Volatile Organic Compound content, low VOC sealers are less toxic).
Types of sealers:
Solvent based sealers can come in gloss and satin finishes. You may need a solvent based sealer to achieve a "wet look" finish.
Water based sealers are generally cheaper, less toxic, easier to apply and clean up and can be applied sooner than solvent based sealers.
Film forming sealers, which are usually acrylic, coming in both water and solvent based varieties, form a protective barrier on the surface of the concrete. These sealers may cause the concrete to become slippery as more layers are added so a non-slip additive may be desired for pool surrounds and steep pathways. Acrylic sealers may alter the look of your concrete to enhance it's appearance and colours. Blemishes and colour variations may also be enhanced so take this into consideration.
Penetrating sealers, silane/siloxant and silicate sealers, penetrate the concrete to form a barrier within the concrete itself. These are good for where water proofing is desired, such as pool surrounds and where a natural look is desired, such as with liquid limestone. They are cheap, longer lasting, water based, odourless, low VOC and are easy to apply. They can be stain resistant and non-stain resistant depending on the product, so check the can before use if this is important to you.
Epoxy sealers are mostly not UV resistant and will turn yellow over time if exposed to sunlight and are not really suitable for outdoors. They are also water proof and can bubble if moisture is coming up from beneath the concrete. However they are durable, easy to clean and perform well. They're often used on garage floors.
Additives can be added to the sealer to give sealers additional properties, such as non-slip grit additives, decorative flakes and colours.
General Sealer Recommendations:
Liquid Limestone - Penetrating natural look sealers
Exposed Aggregate - High gloss "wet look" sealer
Honed Concrete - High "wet look" gloss sealer with non-slip additive
Coloured Concrete - Natural look sealer
Concrete Tables and Counters - Penetrating non-toxic sealer with bees wax polish on top
As there are an abundance of sealers on the market which have varying qualities between them so there is bound to be one to suit your needs and budget. As sealers can be made out of a large range of compounds and additives, be sure to read the can yourself to ensure it has the qualities you need!
Call Steve today and see what we can do for you!