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.  

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.

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.