Settlement

Installing interlocking paver systems is a series of critical steps. When addressing settlement issues you must peal back the layers, assessing the accuracy of each step taken during the installation. This can be done by applying the following information. First determine what type of soil you have on site and how much water it holds. Soils containing +30% clay are described as clay and are prevalent in our area. Clay is very pliable when wet which leads to rutting on driveways. Is your dig in compacted earth or was there a significant amount of fill placed recently in the case of new home construction. 

Immediate considerations must be made considering the Subgrade as it is the foundation that your pavers will be placed on top of.The proper use of Woven Geotextiles will provide soil separation, stabilization and reinforcement over moderate subgrades. Many contractors, to submit a lower bid on driveways, will not include this nor do they inform the homeowner of possible ramifications of not using Woven Geotextiles. Base Material  choice, depth and intelligent installation are each of equal importance to the project. Simply said (not including permeable paver systems) Base Material should be Class II or Class V. Applied in 2"-4" lifts and compacted each lift with proper moisture content. Total thickness of Base Material (after compaction) over well-drained soils varies from 6" for pedestrian areas to at least 10"  for residential driveways. This does not include additional inches in consideration ofSubgrade soil type, drainage/moisture content and climate.The lack of proper Compaction will affect an application very soon after installation and may continue for many years to come. Base Compaction should be done with a vibratory roller or reversible plate compactor. Many contractors make the mistake considering a 4000 flb forward plate compactor sufficient to achieve  the recommended Proctor density. In fact it is if compacted in 2" lifts.  

For the DIY, you can find the most accurate information regarding the different types of interlocking pavers, Woven Geotextiles and Base Material  by contacting Hedberg Landscape and Masonry Supplies. (3 Metro locations) If this is to much- We Can Help ! We make house calls. Just contact The Paver Doctor. We specialize in Paver Repair-Restoration-Sealing.  

Creep

The curved chalk line follows the vehicle tires
into this driveway. Not only do the pavers
creep in this example the bed sand is
pushing outward from the loads.

This picture illustrates Creep. While Creep can happen on patios and walks it is much more common on driveway applications where repetitive breaking or turning loads from vehicular traffic are present. Inappropriate paver shape, thickness, aspect ratio and laying pattern will lead to Creep. Improper choice or installation of an edge restraint system can also contribute to Creep.

All to often creep begins with poor choices. Interlocking Concrete Paver Institute (ICPI) suggests a 60 or 90 degree Herringbone pattern for driveway applications. Not all people like the "look" of this pattern and designers give way to that sentiment allowing homeowners other choices. While short term the homeowner has received what they wanted, long term it becomes a disaster. 

There are multiple edge restraint systems and the ultimate would be a poured in place concrete curb. Concrete curbs will not push outward from vehicular turning loads. Flush concrete beams can also be poured with in the body of an installation to help keep it in place preventing Creep.

Creep affects the structural integrity of an application leading to loss of interlock and joint/bed sand washout. While replacing a driveway using the correct paver and laying patterns may not be feasible, The Paver Doctor has proven methods of repair. Feel free to call regarding this or any other issues related to your pavers. We specialize in paver Repair-Restoration-Sealing.

Cleaning

A variety of methods can be used to clean pavers. A leaf blower can remove leaves and grass clippings. A garden hose with spray nozzle can remove surface dirt. A stiff brush and a lot of elbow grease followed by the hose and spray nozzle can remove even more dirt. And homeowners can include a variety of cleaners. Hedberg Landscape and Masonry Supplies have 3 metro locations where you can find a full line of do it yourself spot and general cleaners available.  

What about the pressure washer? Most pressure washers available at the home improvement stores are over powered and under fed, resulting in pressures that can strip the Cream Coat off of new pavers and old. Finishing concrete and during the manufacture of pavers a Cream Coat forms on the top surface. The surface you see (including the color) hides what is below and that's a lot of small rocks (and not that much color).

The Paver Doctor recommends the use of hot water (160 degrees) low pressure (300-600 PSI) and high water volume (5-8 GPM) to clean pavers. Cleaners need proper dwell, agitation and rinse. The applications must be worked in two different directions. Glass, wood or metal siding, veneer stone or brick and stucco must be protected from acids based cleaners. Consideration of run off into planting beds, lawn and ultimately watersheds will direct what chemicals can be used. 

The key to cleaning stains is to do it quickly after it happens. Reactive  measures are much more successful when a proactive approach is taken. A sealant application will reduce stain absorption. Sealants are designed to prevent the penetration of contaminants including dust, dirt, oil that dull the colors of pavers. Regular maintenance cleanings become quick, easy and much less intrusive to the colorful Cream Coat.

Dirty soiled pavers are both an appearance issue and can affect the integrity of the paver by holding onto moisture which during freeze thaw periods can lead to spalling. Feel free to call The Paver Doctor to assess this or any other issues related to your pavers! We specialize in paver Repair-Restoration-Sealing.

Polymeric Sand

Some of the specialty work we do should NOT be tried by
the DIY and this is on of them

With its many attributes, Polymeric Sand  has become the joint sand of choice on new paver installations. Polymeric Sand  is either a fine or course graded sand mixed with polymers. After placement, the joints are watered in, activating the polymers. After cure the joints harden off which helps resit erosion, weeds and ant infestation. 

Polymeric Sand is also a great solution in high slope areas greater than 7%, high wind areas or areas that experience concentrated water runoff. Preventing joint sand washout that is common with these conditions.

Problematic sand entering into a pool or home can also be solved with the use of Polymeric Sand on pool decks and entry areas.

Installing Polymeric Sand  is relatively easy, although activating the polymers full depth in the joint takes patience and practice. The proper amount of moisture is paramount to a successful activation. Over watering or flooding the substrate will create the polymers to rise out of the joints and over the top of the pavers leaving a Polymeric haze. 

Polymeric Sand does have limitations and is not always the best joint sand choice. Shaded or poorly draining areas will retain moisture and effect the appearance of the finished joints. Feel free to contact The Paver Doctor for more information on Polymeric Sand. We specialize in paver Repair-Restoration-Sealing.         

Look closely to notice Polymeric Haze.
Polymer's are lighter than sand and water thus over flooding
while activating will cause polymers to float up and rest on top of the paver

We use acids to break the bond of polymers to concrete.

Joint Sand

Joint sand is responsible for the vertical interlock of a paving system. High slope areas, water run off, wind and aggressive cleaning can result in erosion of joint sands. Joints should be filled to the bottom of the chamfer or in the case of tumbled pavers 1/8" from the top. Substantial loss of joint sand could result in a loss of vertical interlock affecting structural performance.

Not all joint sands are created equal. Both fine and course Mason sand contains rounded aggregates that tend to wash out (being replaced by dirts). They do not lock together as sands with symmetrical particles. The angular or symmetrical sands take much longer to consolidate in tight paver joints which is why most contractors neglect to use them. 

The picture to the left shows: (from left to right are) Fine Masons Sand, Course Granite Sand and a 50-50 mixture of both. With the addition of the angular Granite Sand, joints tend to stay consolidated longer and in many cases mixing custom blends of joint sands can achieve colors that highlight the colors of the pavers used in the project. 

If you are interested in more information or would like The Paver Doctor to blend a custom joint sand for you please call. We specialize in paver Repair-Restoration-sealing.

Edge Restraint

Edge Restraint systems are responsible for rotational interlock of a paver application. Through interlock, thousands of pavers together will act as one continuous surface. Edge restraint failure will result in shifting/creeping of pavers leaving open joints which will result in bed sand loss leading to possible rutting or settlement. 

The desired outcome of an Edge Restraint is that it stays stationary. Understanding the degree of lateral forces that will be exerted on the system is critical to determining what type to use. With the correct Edge Restraint system in hand accurate installation is critical to its success. Trying to save money on shorter spikes or less of them can cause a failure. And setting spikes into the ground will not hold, they must be driven into base material.

The most common type of edge restraints are made of black PVC and set in place with spikes driven into the base material. On straight runs rigid Edge Restraints are preferred and flexible is used on curve-linear applications. 

Hedberg Landscape and Masonry Supplies (3 Metro locations) provide quality Edge Restraint systems. I have yet to find comparable products at the big box stores. 

Replacing Edge Restraint systems begins with identifying the underlying issue and correcting it. Repairing the damage created by the failure will become more involved the longer the failure exists. If you feel this condition may exist on your paver application feel free to contact The Paver Doctor. We specialize in paver Repair-Restoration-Sealing.

Efflorescence

Most every new paver application has Efflorescence. It can appear as a white stain-see picture below, or a white powder on the top of the paver. Simply said it is a natural occurrence of curing concrete. Technically, curing concrete contains Calcium Oxide and when mixed with water this forms Calcium Hydroxide and when mixed with air becomes Calcium Carbonate, AKA Efflorescence. On a new application it is termed Primary Efflorescence and when it continues we call it Secondary Efflorescence.

The Paver Doctors advises to let Efflorescence run its course on new applications. Sometime within a year from installation, through a process called weather, Efflorescence production will be exhausted. At that time after a cleaning to remove the remaining residue is done you will be free of Efflorescence! 

In specific situations, Efflorescence may need to be removed. With many acids readily available to consumers, I would only suggest one for homeowner use. It contains 16% Solfamic acid which will not damage concrete if used incorrectly. You can find it at Hedberg Landscape and Masonry Supplies (3 Metro locations) and sold under the SRW Products brand.

In some instances Secondary Efflorescence can reappear for longer periods than a year. Cleaning and then sealing the pavers will help two fold. First it will reduce the amount of water entering the paver and also create a resistance forcing any Secondary Efflorescence Blooms to the sides and bottoms of the paver.

Efflorescence is an issue of appearance and will not affect the integrity of the paver. Feel free to call on The Paver Doctor to assess this or any issues related to your Pavers! We specialize in paver Repair-Restoration-Sealing.