Frequently Asked Questions (FAQ)
What if ants or weeds show up in the joints between interlocking brick pavers?
As with any surface that has a crack or seam (cracks in concrete, joints between pavers or pieces of stone, expansion joints in concrete….) ants can become a problem.
In interlocking paver systems, the sand at the bottom half of the paver is what causes lock up between the pavers, making it a durable system. The sand in the joints between the top half of the pavers eventually washes out (with wind, rain, washing of the patio…) and is replaced with dirt and debris from the air. This is actually preferred and we recommend customers allow this process to happen naturally. The particles that replace the lost sand actually compact more solid than sand does, therefore naturally deterring weeds from seeding in the sand, and ants from feeling so welcome.
If an ant problem does occur, it is recommended that granular ant killer be swept into the joints between the pavers.
If weeds are a problem, keep in mind that the weeds are growing from seeds falling into the cracks between the pavers, from blowing seeds or bird droppings. The weeds are not growing up from under the pavers. As mentioned above, once the top layer on sand between the paves is replaced with dirt and debris from the air, the more compacted material will make a weed problem less likely. Since the weeds are not growing up from below the pavers, the roots are small and therefore easily pulled out or controlled with a general weed killer.
If we can be of further assistance or answer any questions for you, please do not hesitate to contact our office or the project coordinator that worked with you on your project.
What is efflorescence?
Occasionally customers are concerned with the white discoloring that sometimes appears on recently installed paver projects. Creative Hardscape Company would like to provide you with some information that will hopefully ease your concerns of the problem.
The white haze that is appearing on your paver project is called efflorescence. Efflorescence is a natural process that occurs with all concrete products. When cement hydrates (hardens after adding water), calcium hydroxide is formed. This calcium hydroxide is soluble in water and migrates to the surface after moisture enters the pavers. When this chemical mixes with the air, it forms calcium carbonate, which is the white discoloration that you are seeing.
The efflorescence sometimes appears immediately or within a few months after installation. If installation occurred during a dry period of the year, a cycle of wet weather can cause efflorescence to materialize. This is a good thing. The wet weather is drawing the calcium hydroxide out of the pavers, which is what needs to happen to eliminate all future efflorescence. In Colorado, we typically see that the severity of the efflorescence diminishes each time it appears, and will completely resolve itself in short order.
There are commercial efflorescence remover products available. The cleaners contain acids, blended with other chemicals. Creative Hardscape Co. does not recommend the use of these products for several reasons. First off, the cleaning products cause the same process to occur that environmental moisture does, pulling the calcium hydroxide out of the pavers. We see no need to expose our customers or employees to harsh chemicals when environment moisture will take care of the problem just as effectively.
If pavers are cleaned with a chemical cleaner, it is often necessary to repeat the process several times to fully rid the pavers of efflorescence. The cleaners contain extremely harsh chemicals that are harmful to our employees to work with and harmful to the environment. They are also damaging to existing plant life. We have also had experiences where the chemicals have permanently discolored the pavers and or exposed aggregates on the surface of the pavers. In our experience, we have found that letting the efflorescence run its natural course, leaching out as a result of moisture sitting on the pavers, is just as effective, without the use of harsh chemicals.
Please be assured that Creative Hardscape Co. is a locally owned and operated company that takes customer satisfaction very seriously. If you decide, after reviewing your options, that you would like us to chemically clean your project instead of letting the situation resolve itself naturally, we are happy to give you a bid for this work.
Why is sand used in the construction of a sand set paver system?
In the construction of a sand set paver system, sand is used for a couple of reasons:
1. Most importantly, to achieve vertical interlock. “Vertical interlock is achieved by the shear transfer of loads to surrounding units through sand in the joints.”
To achieve this, 1” of bedding sand is placed between the subgrade base material and the pavers. The pavers are then vibrated with a plate compactor, forcing the sand into the bottom half of the joints of the pavers. This is the sand that creates vertical interlock.
2. To fill the upper half of the joints for aesthetics. Once the pavers are laid and compacted into the bedding sand, sand is swept into the top half of the joints. The pavers are then compacted again, to assist the sand in filling the joints completely.
Inherent in paver system construction, there is initially excess sand on and in the upper potion of the joints between each paver. This excess sand is lost (or tracked into your home) through wind or washed away with rain in a short period of time. During this period of settling, voids (or “pin holes”) may be seen. In time, dirt and debris coagulate and a natural seal is formed and the joints will again appear “full”.
Hosing off or power washing the pavers can exaggerate the lost of the excess sand. This may extend the amount of time needed for the joints to fill with dirt and debris, but will not structurally harm your patio because the sand causing interlock is in the lower half of the joints.
Some people are tempted to keep sweeping sand into the joints when voids are seen. This, once again, will not harm the structural integrity of the pavers, but will extend the amount of time needed for the joints to fill with dirt and debris.