Paver Stone Maintenance Tips & Guide
Homeowner Paver Stone Maintenance (Zone 9B Sacramento, CA)
Maintenance of your pavers
Maintaining your paved area is not something that should take a lot of time, but it should be regularly done. In general, there are a few things to keep in mind:
- Preventing Weeds
- Preventing Ants and other boring insects
- Maintaining Joint Sand
- Cleaning Stains and Efflorescence
- Snow and Ice removal
- Patina and Wear
- Settling Pavers
It is inevitable for grass and other plant seeds to blow into the joints of your pavers and become lodged. Over time, they will germinate and put roots down into the cracks. This is, arguably, the number one enemy of paved areas. Some weeds have very strong taproots that, if allowed to grow can actually start to erode your base and crack your pavers.
Even if they do not cause drastic damage, plant roots can and will dislodge joint sand if you are constantly pulling them up. Using sealers can help prevent this, as can regularly using herbicides. However, if you are going to use herbicides, be aware that they can drain into ornamental areas and destroy plants there. It is recommended that homeowners use biodegradable herbicides.
Preventing Ants and other boring insects
Ants and other boring insects love the hollow spaces between the compacted gravel and the sand above it. This is practically an exact replica of their natural habitat, and you created it for them. If ants catch wind of this area, you may find them to be problematic. In general, they don’t cause damage to the pavers themselves or the underlayment, but they can be pesky. Use a mild pesticide to get rid of them. Ants do not require strong pesticides.
Maintaining Joint Sand
Over time, dust and dirt tend be blown and trampled into the joints of your pavers. This is a natural process and can actually benefit the pavers by keeping the joint sand in place. However, on steep grades and in other extreme circumstances, the process may be the opposite. Instead of a heathly buildup of dust and dirt, there may be an unhealthy erosion of joint sand. Homeowners should keep an eye out for this problem. If it is noticed, simply replacing the lost sand. An easy way to do this is with a broom or brush. A more permanent solution would be to seal the paved area.
Cleaning Stains and Efflorescence
Stains and efflorescence are practically inevitable. At some point in your paved area’s life, something is going to leech out or spill onto it, creating a stain. There are several cleaners you can use for different kinds of stains, but first, you may be wondering what efflorescence is and what causes it.
A little while after you have your pavers installed, you might notice a white haze on top of them. This is normal and natural, and it does not mean that anything is wrong with your pavers. It is called efflorescence.
The way Efflorescence works is like this:
The cement that is used to make your pavers has water soluble calcium oxide or lime in it. When this comes into contact with water, either when it rains or when you water your grass, it creates a chemical reaction. The pavers have microscopic capillaries in them, which pull the water in. The water reacts with the calcium oxide and produce calcium hydroxide. The calcium hydroxide, in turn, rises to the surface and reacts with carbon dioxide. This second chemical reaction forms calcium carbonate when the water dries. Calcium carbonate, of course, is white. And this is what causes the efflorescence – the white haze or coating – to appear on your paver stones after it rains.
Efflorescence is not bad for your pavers. It doesn’t mean they are disintegrating or that the seal isn’t good. It will naturally stop when all the calcium hydroxide is gone.
Efflorescence is a natural Chemical Reaction
It should be noted that practically all paver stone companies putt additives in their pavers to reduce efflorescence. Even so, it cannot be completely prevented because it is a natural chemical reaction that happens within concrete. It may happen in concentrated areas or randomly across the entire surface of your paved area, though it should be noted that the darker your pavers are, the more noticeable any efflorescence will be.
It is important enough to repeat that, if you notice efflorescence in your pavers, this is not a structural problem. Your pavers are just and strong as they have always been. They just look stained or faded. And just like spilling oil or paint on them, this can be removed with concrete cleaners, like a solution of muriatic acid specially formulated for concrete pavers. Be extremely sure that any cleaners you use are formulated for concrete pavers or you risk actually causing permanent discoloration or other permanent damage to your pavers.
For Other Stains, not caused by Efflorescence
For stains not caused by efflorescence, different types of cleaners may be needed. The chemistry of removing calcium carbonate from efflorescence and oils, paints, and other stains can be very different and there may be more than one step required. For example, if you use a formulation of muriatic acid, you will need to neutralize any residual acid with another chemical such as baking soda so that it does not continue to eat into your concrete or harm any plants or animals when it runs off the pavers.
Oil stains are common on concrete and pavers, alike. They are also notoriously hard to remove. For this reason, here are a few guidelines for taking care of this particular nuisance.
Cleaning Oil Stains on Paver Stones
- Treat oils stains as soon as possible. While it may seem counterintuitive because they are essentially stone, concrete and brick are permeable, liquids will pass through them, slowly. The longer you let oil sit on your pavers, the deeper it will penetrate and the more difficult it will be to get it out. First things first, wipe up any standing oil immediately.
- Put an oil-busting detergent or soap on the stain. In general, this can be any concentrated detergent, but detergents specially formulated for concrete will work the best and you will not run the risk of damaging your concrete.
- Let the detergent sit for a few minutes.
- Rinse with hot water. It is important that the water be hot, not just a cold hose. The heat helps extract and break up the oil by enhancing solvents in the detergent.
- Repeat as necessary. Keep in mind that allowing detergent to sit for too long can create an entirely different kind of stain. As logical as it may seem, you will not help the oil stain by allowing the detergent to sink in and create a new stain.
If you know that your paved area will be a high traffic area for vehicles, it is recommended that you use a sealer on your concrete pavers as this will waterproof/oil-proof your pavers and make clean up much easier while preventing stains. Keep in mind, however, that you will need to reapply sealer at regular intervals.
Snow and Ice Removal
Unlike solid concrete slabs, which are actually expected to crack from the freeze and thaw cycle, pavers are naturally resistant because they have natural joints. Salts and salt-sand mixtures can be used on pavers. This may actually help, to a small extent, replenish eroded joint sand and prevent weeds in the warmer months. Just like concrete and asphalt, you can use shovels and plows without any ill effect, when used properly. For northerly climates that receive increased snow and icefall, installing a liquid or electric snow-melting system is another option and these systems are very popular and work well with pavers.
Patina and Wear
The color of your concrete pavers is permanent. It will not fade appreciably over time, though erosion and dirt due to traffic over the pavers can create an aging effect or patina. This is caused by foot traffic depositing dirt into the microscopic holes and fissures on the surface of the pavers, allowing it to sink in and darken the overall color of the pavers. This effect can be quite beautiful, and it is a very natural process, but it is not always desired by homeowners. To prevent your pavers from gaining a patina, the use of a sealer or regular cleaning is recommended.
Settling pavers is generally caused when the gravel base layer or the soil below it was not satisfactorily compacted prior to installing the pavers. If the soil or gravel is loose, it will shift or erode over time causing the pavers to settle, creating a pothole effect. Another possible issue is if the bedding sand layer was put in too thick. This can be common when a paver installer gets into a hurry and does not level the gravel base. If he finds that the gravel is too low in one area, he may try to compensate by putting in a too thick layer of bedding sand. While there is some leeway for using bedding sand to level out pavers, there is a limit, around one and one half inches, where the sand stands a high risk of washing out or settling itself, and causing the pavers to settle in turn.
If pavers in one area are uneven or have settled, for whatever reason, they can be removed, the underlayment adjusted and then repaved. If the soil under the base is the root cause of the setting, the issue can be more complex. If it has settled but is now stable, adding some gravel to the base layer and then compacting it to even it out is all that is required. However, if the soil is not stabilized, then other processes must be used to stabilize it before repaving.