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How to Install an Interlocking Concrete Paver Driveway

                In St. Louis, MO, where Agape Retaining Walls, Inc. (http://www.agaperetainingwalls.com) is located, I am always amazed as I drive through subdivisions every day and see cracked and broken driveways originally built using concrete or asphalt.  It does not amaze me that 10-20 years ago someone had a driveway in St. Louis installed using concrete or asphalt; it amazes me to see them using those inherently flawed hardscape products today when they have an alternative product to install on their driveway or sidewalks such as interlocking concrete pavers, that when installed correctly have no competition in terms of performance, design flexibility, looks and longevity!  To say that interlocking concrete pavers have no real competition is no exaggeration.  It is a fact!  When the rules of proper concrete paver installation laid out by the ICPI (Interlocking Concrete Pavement Institute on the web at: http://www.icpi.org) are followed you can be confident that your driveway will not sink, crack, or encounter any other problems that plague concrete and asphalt driveways in areas of the country like St. Louis, MO, where the freeze thaw cycle is a real consideration, because interlocking concrete pavers have flexibility. Interlocking pavers have the ability to flex with the freeze thaw cycles unlike other rigid driveway products, like concrete, that when subjected to freeze thaw will crack and break. Interlocking concrete pavers are not damaged by the freeze thaw cycle! Interlocking concrete pavers have been used for decades all over the world including countries such as Germany and Canada where the winters tend to be much colder than in St. Louis, and the pavers have shown amazing durability.

 1.  Getting Started on your Do It Yourself (DIY) Interlocking Concrete Paver Driveway      

                The very first thing that you will need to do to get the ball rolling on this interlocking paver driveway project is to check with your local municipality to see if they require a permit for the type of work you will be doing. At this time in St. Louis County, you do not need a permit to install interlocking concrete pavers. Always make sure to check just to make sure before you go tearing out that old concrete driveway. Another important thing to check into is your subdivision rules. If your subdivision has old obsolete rules requiring concrete or asphalt for your driveway replacement do not take no for an answer!  Work to get the rules changed to permit interlocking concrete pavers for your driveway hardscape.  You and your neighbors will be very glad you did.  One last thing to make sure you get done before any excavation of your  old driveway begins is to call in the locates for your utilities! In Missouri we call 1-800-DIG-RITE for our utilities to be marked.

                After the local rules, subdivision rules, and utility locates have been checked and  taken care of, you are now ready to start your interlocking concrete paver driveway project. The first thing you will need to consider is that you will need help! Make sure you have at least 2-3 people lined up who you can count on to help you out during the installation of your driveway paver project. This would be a good time to check into the different equipment rental companies in your  area to compare rates and to make sure the equipment you will need  to install your interlocking concrete driveway will be available when you need it.  Equipment that you will need to check on are a mini excavator, skid loader, laser level, plate compactor and a  vibratory roller. Also, take your time and do your homework on the type of paver you wish to install on your driveway paver project. Pick out a paver pattern to install that you like and are confident you can install yourself. Become a student of each type of paver;  make sure you read the recommended installation procedures  for the type of paver you have chosen to install.

2. How to Choose Your Interlocking Paver Brand, Type, Color, and Pattern

                The choice of what brand, style, color, or pattern to use for your interlocking concrete paver driveway has never been more difficult! Your options in paver products are nearly endless. That is a good thing if you are willing to do some research and study these options There are so many different brands of interlocking pavers you may wish to use. Three of the best of these are Belgard, Romanstone,  and Pavestone. My preference in brand selection here in St. Louis most of the time comes down to Belgard Pavers vs. Romanstone Pavers. They both have very high quality paver products with large selections and styles.  My advice would be to do some shopping around and find out where you can find a Belgard or Romanstone supplier where you live and go look at the products, colors, pricing, and warranty of  the product along with who will give you the most assistance in the form of technical support if you run into a problem in the field. I must note that Pavestone and Bella Stone both seem to have some great products. However, at this point I have not installed with them. Styles of pavers vary widely and you will want to confirm that whatever style of interlocking paver you choose  is approved for use on a driveway. The simplest style of paver to use for you the homeowner wishing to install this driveway yourself is the Holland Paver. The Holland Paver is a great paver for many reasons. It is very common, so all suppliers should have plenty in stock. The Holland paver comes in a wider variety of colors than most any other style of paver. The Holland Paver can be installed with more color blends, more patterns and with very well defined borders; you can mix several color blends of pavers together, or use solid colors to define the edges of your  driveway with a border. The Holland Paver is the most versatile and easiest to use.

                In deciding your color you will need to decide if you want to match or contrast the color of your home. You will need to take into account the optical effects of darker colors that tend to absorb light and make an area seem smaller vs. lighter colors that reflect light and help make an area seem more open. Also, the pattern you choose for your pavers can make an area look larger or smaller. It can also be used in conjunction with paver borders to define an area or lead the eye to a desired place in the hardscape project. The whole process of paver colors, patterns, and even textures can be very complex depending on what you wish to focus on in your design so make sure you do an in depth study of the effects of all your options and custom design the option that will best fit what you want in your new paver driveway.

3. How to Lay Out Your Driveway Paver Project

                To lay out your driveway paver project you will need to ask yourself several questions. What do I need to center off of?  What elevation will I need to maintain? Renting a laser level for this would be a good idea. How much slope do I have figured into this paver  driveway?  My recommendation is to keep the driveway paver layout as simple as possible. On most driveways you will be centered off the garage and you will be maintaining the same slope from the garage to the street as the original driveway. The ICPI (Interlocking Concrete Pavement Institute)  minimum recommended slope for a driveway paver project is 1.5%  or 1/8” per foot drop to allow for proper water runoff.  Make sure to set your driveway slope where the water is flowing away from your home. If you have a driveway where the existing driveway runs down into the garage you will need to make sure to have a proper drain running across the garage entrance to prevent water from flowing into your garage. When laying out the dimensions of your paver driveway make sure to plan on your excavation going beyond the borders of your driveway by a minimum of one foot. This will give you room to compact your  rock base all the way out beyond the edge of the pavers and also provide a strong sub-grade to hammer your paver edging into. Lay out the borders of your paver driveway with metal or wood stakes.  Make sure you offset the stakes at least 1-2’ past your driveway excavation marks so that the stakes do not get dug out during the excavation of the driveway.

4. How to Excavate Your Driveway Paver Project

                Before any driveway excavation begins make sure that all utilities have been marked and that where there are marked utilities in the driveway area make sure you dig these area by hand and be very careful! Now that you are ready for your driveway excavation you will need the right equipment to excavate your driveway. The most important piece of equipment in the excavation of your driveway is a mini excavator. Make sure to get one big enough to do all you need it to. I would suggest two buckets; one with teeth to excavate anything hard or rocky and a 3’ wide smooth bucket for bulk excavation and crumbing out or removing all the loose dirt and unwanted materials from the sub-grade. There are other pieces of equipment that you can use but the mini excavator is very efficient and much easier to operate than almost any other equipment you may choose to use in the excavation of your driveway project. When figuring out how deep to dig for your driveway base, take the depth of your paver, (minimum paver thickness for a driveway is 2 3/8”) add  ½”-1” for your sand and the 1’-2’ for your base rock depending on the type of soil you have for the sub grades, the climate, and the maximum weight and frequency of traffic.  It is crucial to make sure that the soil below the base is solid! Unless you have a good understanding of different soil types and characteristics of the soil you are working with it is my advice to get a soils tech to look at your soils! Get the opinion of a professional! If you have it set up ahead of time they should be able to get out the same day to test your sub soils.  It does not cost much for this service and it will comfort you in the long run to know that your sub soils are good and able to bear the load of your driveway. The soils tech or your engineer will be able to better guide you on your rock base depth after the soil has been tested, so you will need to know the depth of your rock + paver depth + sand to know how deep to dig for your driveway paver project. When it comes to where to dig you will need to lay out the borders of your interlocking concrete paver driveway and dig out at least 1’ beyond the borders. This will provide a solid area to put edge restraint spikes into a solid compacted rock and will also make sure that the edges of your driveway all are supported by a strong, well compacted rock base. One last thing before you start the excavation of your old driveway – you will need to have a hauling company lined up to haul away all the extra dirt and materials you will produce in the excavation of the existing driveway. Make sure to call around, compare haul rates and make sure that you and the hauling contractor have an agreement, preferably in writing, on the amount you will pay per load hauled out and the method of your payment. Have this arranged before your driveway excavation begins and make sure that you have a way to get rid of all the extra material you will have on site during your driveway excavation.. The amount of excavated material will shock you. As a rule of thumb take your length x width x depth for your Square Yard number + 25-30% expansion for clay soils as they get dug up! Another important point to make sure of with the hauling contractor that you chose to hire is that they have a smaller dump truck that will be easier and faster for you to load up.

5. How to Install and Compact Your Base Rock

                If  you have not already brought in a skid loader to speed up the extra dirt being loaded in dump trucks you will need a skid loader now to move the rock in for your driveway base and smooth it out. You will want to make sure that your rock base is a 1-2” minus rock and that it is installed in lifts 4-6” maximum depth. You will also need to make sure that you have several heavy compaction pieces of equipment on site to guarantee that your rock is compacted well enough. Also, before the rock base is installed is the time you would put in a geotextile material if you wish to use one. This material can be either woven or non woven  fabric and is to be placed under the base rock material. The use of a geotextile fabric is optional but has shown to be very effective at preserving the load bearing capacity of the base over a longer period of time than base placed without geotextile fabric. If you use the geotextile material you will need to make sure that it is installed wrinkle free and that as you drive in and out of the driveway area bringing the base rock  in one bucket at a time that you do not turn or drive in a manner to produce wrinkles in the geotextile material. As you are placing your minus rock in for your rock base under your paver driveway you will need to take care not to use any frozen material and that the ground under the rock is not frozen. As you rock in your base rock lifts it would be a good time to have the soil tech come out and test the density and moisture of your base rock compaction. It is very important to get the right compaction in your rock base. There are several types of compaction equipment that you can use for your  driveway paver project such as forward plate, reversible plate, vibratory rollers and maybe even a jumping jack for compacting up close in an area where other compaction equipment cannot work effectively. You should be able to rent these different types of  compactors from the same place where you rent the mini excavator, skid loader ,and laser level.  Making sure that the sub soils are solid and the rock base is placed and compacted correctly is the most vital component to the long term success of your driveway paver project.

6. How to Set Your Bedding Sand For Your Paver Driveway

                It is important to get your base rock exactly where it is supposed to be! When your base rock is perfect it will keep the bedding sand uniform across your driveway.  It is very important that you do not use the sand to fill in low spots on your rock base. The sand should in no case be deeper than 1” maximum depth. We like to get it ½” to ¾”  for our paver bedding sand. You will need to purchase some ¾” PVC pipe to use as rails for your paver driveway bedding sand. The outside diameter of a ¾” PVC pipe is 1”.  If your rock is right on you should be able to just set your rails down on the rock base and place bedding sand around them to hold them in place while you use a straight 2×4 board to drag the bedding sand across the two rails. So, space your rails 7-8 feet apart laying them down on rock base.  Now have sand dumped between the rails with a wheel barrel keeping the piles of sand smaller and easier to move and use as needed.  You will need to knock down any sand piles that will be to hard to drag. You can knock these sand piles down using a rake or shovel. Now you are ready to drag off your sand by placing  the 2×4 across the rails and pulling the sand toward you leaving behind a perfect bedding area to place the pavers onto. You will need a trawl to help fill in the areas where your PVC rails are slid down for the next section of sand to be placed or taken up at the end. To fill in these areas left by the PVC, place some sand with a shovel in the areas to be filled in then use your trawl to smooth it out being very careful to keep this area level with the sand around it. Use this method to place all the sand you think you will be able to cover with pavers that day.

7. How to Start Laying Your Paver Driveway

                Begin to install your interlocking concrete paver driveway one hand set paver at a time. Whenever it is possible you will want to install your pavers moving from the low elevation to the higher elevation. You will also want to make sure you have staged your materials as close as possible and set up the project so that you will be moving needed pavers across the paver driveway as you lay the pavers. You will need to make sure your paver pattern is squared off of whatever object you are placing as your point of reference when installing a straight driveway. Most of the time on a driveway you will square your pattern off the garage or the home. You can use a metal triangle to square your pattern off the house or the 3-4-5- method also works well.  When you have your paver pattern squared off the reference point you will want to set up string lines now to guide your paver installation as you move across the driveway to make sure you are keeping your paver pattern square to the garage or home. Many times you will want to start your paver pattern at the corner of the garage or home and begin to work across the drive and then away from the garage or home. In this case make sure that the first row of pavers coming off the garage or house is straight. Many times people will begin their driveway paver installation by placing the pavers up to the garage concrete just assuming that it is straight and they get messed up in their driveway paver pattern because the garage, house foundation or even a curb or sidewalk may have inconsistencies! These inconsistencies are very slight as a rule and if there are some small ones we need to set the pavers away enough from the foundation to guarantee that they are straight in their pattern. The pavers that are just a little away from the garage or home will be filled in with polymeric sand later and will not be a problem. However, if the paver pattern gets off track it will cause a big problem and a not so nice looking paver driveway. Now as you start to install your driveway  by hand placing paver by paver in the pattern  you have chosen squared off the garage or home you will hear a click sound as you put each paver down. You will use the click and drop method as you install each concrete paver. Use your strings as a guide and gauge to make sure your paver pattern is staying straight. When all your pavers are laid you can use a straight edge or plastic PVC pipe for curves to mark where the end of the boundaries are. Use a mason crayon to mark the edges for your cuts. Now you will need to fire up the concrete saw and begin making the cuts as needed to complete the edges of your paver driveway.  Before you fire up the saw make sure that you have proper safety glasses to protect your eyes, ear protection, and a proper respirator to help protect your lungs. You will need a diamond saw blade on the two cycle saw or wet saw that you are using. If you are cutting in a radius on your driveway install your plastic edge restraints in the curved area and place all your pieces in. Make sure to nail every hole on the edge restraints.  Now all your cuts are complete and in place and it is time to install your remaining edge restraints.

8. How to Install Your Driveway Paver Edge Restraints

                 When installing paver edge restraints it is very important to make sure your plastic edge restraints are strong enough to hold over time. Make sure that you talk with your supplier and read the specs on the edge restraints you use before you install them. One common mistake many people make when installing edge restraints is not clearing off the sand on the rock. Put the flat edge of the edge restraint up to the side of the paver. Make sure that the edge restraint is flat and tight up against the side of the paver and firmly flat on the base rock below. Hold it with your foot and make sure to put a nail in every hole using at least a 2 lb sledgehammer to hammer down the 12” nails. Now that all your edge restraints are installed to hold your driveway pavers in place we can move on to the first plate compactor run over the pavers.

9. First Plate Compactor Run Over New Paver Driveway

                Now you need to use a plate compactor to whack down all the pavers level going from the outside and moving toward the center. You will need ear protection and eye protection to do this so make sure that you have headphones and safety glasses before you start. After you have this done  make sure you look over the driveway for  any pavers that may have been cracked by the plate compactor. In the rare case that you find any cracked pavers replace them before moving on to the next step in your interlocking driveway paver project. Most of the time there will be no cracked pavers but if there are, now is the time to replace them. The process of taking out a cracked paver before the polymeric sand has been applied is easy. Most of the time a flat head screw driver will do the trick. After the paver has been replaced, place a new paver in and make sure it is level with the surface around it by adding a little sand as needed and tapping the paver down gently with a rubber mallet . Now it is time for the final step in  the completion of your interlocking concrete paver driveway.

10. How to Install and Activate Polymeric Sand on Your Paver Driveway Project

                Talk with your supplier about the most effective polymeric sand to use and make sure that you read all of the manufacturer recommended  installation procedures. After the driveway pavers have been compacted without sand on the top now it is time to start putting down the dry polymeric sand and sweeping it in. As you sweep in the polymeric sand make sure that you have a mask to help protect your lungs from the polymeric dust. As you sweep in the polymeric sand into the paver joints in the driveway, first sweep in one direction, let’s say north-south, then sweep in another direction let’s say east-west.  Different directions make sure all the edges are filled in. After you sweep all your polymeric sand in all the joints very well making sure they are all filled to the top, sweep all the extra sand off the pavers. After this take a leaf blower and blow any extra remaining sand off your paver driveway making sure not to blow all the polymeric sand out of the paver joints. Look the driveway over very well one last time making sure all your paver joints are filled. Now it is time to activate the  polymeric sand. It is really important for you to read the directions for the specific product that you are using. Every type of polymeric sand has different ways the manufacturer recommends for the proper activation of their product. It is also very important to have all loose sand off the pavers before you activate them with water. You do not want the polymeric sand to activate on the surface of the pavers. Now that you have activated the polymeric sand and followed the manufacturer’s recommended guidelines for how long to stay off the newly  activated  polymeric sand only one more thing needs to be said.  Congratulations on completing your new interlocking concrete paver driveway!  Be prepared for the jealous neighbors; jealous that you now have the best driveway in the neighborhood!

                One thing that is not needed for your interlocking concrete paver driveway but many people like to use to help protect their interlocking concrete paver driveways, sidewalks, and patios is an interlocking concrete paver sealer. This product will help your pavers stay new looking longer and works very well as long as it is installed correctly. As with every other step in your driveway project I would suggest that you talk with several suppliers, do your research on the different types of sealers and make a choice as to which driveway sealer will work best for you. It is very important that if you do use a driveway sealer that you follow the instructions to the letter. 

                Thank you so much for your time! I hope this hardscape blog has helped you in your decision to install a new interlocking concrete paver driveway. If you have any questions do not hesitate to call us at 314-846-2777 or email us at agaperetainingwalls@yahoo.com.

How to Build a Structural Retaining Wall

               How to build a structural retaining wall is a question you are interested in or you would not be reading this. You have come to the right place. I am the president of Agape Retaining Walls, Inc. and I have more experience in the design and construction of modular block retaining walls than 99.9 % of the people on the planet. I love what I get to do for a living and it is my pleasure to share my knowledge of retaining wall construction with you.

STEP 1: RETAINING WALL PERMITS AND ENGINEERING

            If you are going to construct a retaining wall the first thing you will need to find out is what the local municipality building regulations are for the construction of retaining walls in your area. This knowledge will let you know if you need a retaining wall building permit and if so what you will need to do to get that retaining wall building permit. After finding out what the building codes are in your local area make sure to follow those codes in the planning and the building process. In St. Louis County, MO the local retaining wall building code calls for a retaining wall permit on any retaining wall 3’ or taller exposed height and any retaining wall over 6’ exposed height needing to be engineered by a qualified retaining wall engineer. If you are planning to build a structural retaining wall you will need to have that retaining wall engineered to insure that your new retaining wall will be built strong enough to last for as long as it is needed. The engineering for your project will take into account your soil types and the type of pressures that will bear upon the structural retaining wall. It is very important to follow the engineering in the construction of your retaining wall. When you deviate from the retaining wall engineering in the construction of your retaining wall, you make yourself the engineer and therefore make yourself responsible for any problems the retaining wall may encounter. For the engineer to design your retaining wall he or she will need to have some key information. The engineer will need to know the type of retaining wall system you are using, how tall the retaining wall is, what it is retaining, and the location of the retaining wall.

STEP 2: RESOURCES NEEDED TO BUILD YOUR RETAINING WALL

            Now that you have all the boring stuff out of the way, you will need to take inventory of the equipment, tools, and products you will need to make your retaining wall construction project go as easy as possible. It is my recommendation that you get at least one or two other people to help you; most 8” tall retaining wall blocks weigh about 85 lbs each, so it is always nice to have another set of hands to help. Also, having a second person can be a matter of safety if there is another person on site and something unexpected happens, having someone there to help you in an emergency will be priceless. Another thing that I would recommend in your retaining wall construction is a mini excavator to excavate your retaining wall footing and the retaining wall dig out as needed for your geo-grid. Mini excavators can be rented as needed for your retaining wall construction. It is my advice to call around to several equipment rental places to make sure you are getting the best price. Also, it is my advice that you do some research on the piece of equipment you wish to rent to make sure that it will be able to do what you need it to in your retaining wall construction. I also would recommend that you test drive the mini excavator and all equipment you plan to operate around the retaining wall to make sure you know how to operate it well before you begin your excavation.  Another piece of equipment that I recommend is a skid loader. Make sure to rent a skid loader large enough to pick up the weight of a full pallet for the type of stone you are planning to use for your retaining wall. A skid loader will come in very handy for moving large quantities of rock and stone into place as needed. This will speed up your retaining wall installation. When operating equipment like a skid loader and mini excavator it is my recommendation that you make sure to wear proper ear protection. It is not a bad idea to wear safety glasses and when hauling large quantities of minus rock to wear a mask or air filter to prevent breathing in fine rock particles that may blow out of the skid loader bucket into your face. Another crucial piece of equipment that you will need to set up a large structural retaining wall is a laser level, tripod, and pole that will be used to make sure all your retaining wall elevations are on the mark. There are many other smaller tools that will be needed during wall construction:

  • a very good level– I prefer the 3 l.f. long Crick level.
  • a heavy rubber mallet to do your footing and straighten the retaining wall
  • a measuring tape 
  • a hammer
  • 3lb sledge hammer
  • a string line
  • a concrete saw with a diamond blade
  • retaining wall adhesive
  • wooden or metal stakes to hold your string
  • marking paint for layout
  • filter fabric to keep the backfill clean and allow water penetration
  • geo-grid
  • retaining wall blocks
  • lots of rock

STEP 3: GET PERMITS FOR YOUR RETAINING WALL

            Now that you know what you are going to need to start your retaining wall project, let’s get things started. Pick up your retaining wall permits and keep them displayed on site so that the retaining wall inspectors from your local government will know that your retaining wall plans have been approved and that you are doing things by the book. Beginning your retaining wall project without your permits displayed could lead to a stop work order that could be a long delay to your retaining wall project, as well as a fine.

STEP 4: STUDY RETAINING WALL ENGINEERING AND MARK THE LAYOUT

            Next, study the retaining wall engineering to make sure you have a very good working knowledge of what the engineer wants you to do in the retaining wall construction. Keep referring back to the retaining wall engineering to make sure you are doing everything to plan. Then measure out the exact location of the retaining wall. You can hire a company to mark your property lines or even the exact location where your  retaining wall will be located. If you choose to figure out the location of the retaining wall yourself make sure that you use the scale on the engineering. Take note of the depth of your retaining wall block along with the rate of step back per row installed. Include these measurements in your retaining wall lay out to make sure you have the proper location marked at the bottom of your wall adjusted as needed to make sure the top of wall ends up where you want it. After you have the location of your wall marked out you will need to shoot the elevation from the place where you want the top of your retaining wall to end up when the retaining wall is complete. Take your laser level (You can rent a laser level from most places that rent equipment) and shoot the elevation for the top of your retaining wall. Make sure the place where you shoot this elevation is a landmark that will not change. You will always have this landmark to go back to as a reference point. When you have that number on the bean pole transfer the height of the new retaining wall onto the bean pole. So, when you are going down in elevation you will go up on the bean pole and when you are going up in your elevation you will move the receiver down on the bean pole. So if the retaining wall you are building starts 10’ lower than the top elevation from your landmark elevation and you are toning for final top of wall grade you will go up 10’ in elevation on the bean pole with the receiver to get a tone for the bottom of your retaining wall. In this case however, you will also bury at least 10” of retaining wall below the finish grade and you will need at least 6” for footing rock. So in the case of this 10’ retaining wall you are building you would tone the top of wall elevation, raise the receiver 10’ on the bean pole for the height of the retaining wall, then raise the receiver another 10”  on the bean pole for the buried stone, then raise it another 6” for the footing rock. This will give you the depth that you need to be on your dig out. Now have your helper hold the beanpole and receiver while you follow the paint marks you have made for the wall dig out. When you are at the proper depth the receiver will tone. After you get the footing dug out and everything tones across your footing rock trench you will need to take a smooth shovel and go through the trench for the footing and remove any loose dirt. If you have a soils tech to check the soils type now would be a good time to have them come out to make sure the soil you are building on will be able to bear the load of your new wall. Sometimes the retaining wall engineer will want to see the soils at this point. 

STEP FIVE:  INSTALLING FOOTING ROCK

            Now you are ready for the footing rock. In the past we would always use 1” minus compacted in 3”-4” lifts with a plate compactor or a 6” lift if we were using a Sheep’s Foot compactor. There is nothing wrong with still installing your footing rock with that method, but over the last 3-5 years we have abandoned the minus rock and have switched our footing rock to 1” clean. It is my recommendation that your footing rock be 1” clean rock inside a trench with filter fabric used on the walls of the trench to keep dirt out of the clean rock. The clean rock is more expensive but has several clear advantages over minus rock. One advantage when you use clean rock is that compaction is not the same issue. You can use 6” clean rock in your footing and tighten it up with a plate compactor and you will not get settlement.  Secondly, along those same lines, minus rock has to have a certain amount of moisture for optimum compaction.  If you have to much moisture it will pump and be unstable and  if you do not have enough moisture it will not compact correctly. 1” clean rock removes these potential problem and has another advantage in that it is not susceptible to erosion in the same way as minus rock is. Clean rock will allow for water to  flow through it and will not allow for hydrostatic pressure to build up. 

Now that you have decided on 1” clean rock for your footing, and the footing trench is dug out, you need to set the beanpole for top of your footing rock so that your footing rock will be right on allowing your retaining wall base course or footers to be installed more easily and with more speed. To set your footing rock right on just lower the receiver 6” on the beanpole. You should also pay close attention to the beanpole to make sure all your measurements are correct since some beanpoles are in feet and inches and others are in tenths. After you have your top of rock right on you will need to hop in that skid loader and start bringing in rock for the retaining wall base. Your helper can hold the beanpole and guide you as to how the rock looks in the trench. Some people prefer to have the person holding the beanpole to keep toning the trench as you fill in the rock and after rake it all out perfect then run over it several times with a plate compactor to make sure all the rock is nice and tight. If for some reason you do not have a helper to tone the rock as you move down the trench you can tone the sides of the trench yourself and mark the exact elevation with paint. This will give you a bench mark to guide you on the amount of rock you need as you install your footing rock. After all your footing rock is installed go back through and rake it to the exact elevation and tighten it up with the plate compactor. Now you are ready to start the base course of retaining wall blocks .

STEP SIX: INSTALLING BASE COURSE OF RETAINING WALL BLOCKS

            If you are using a standard 8” building block for your wall, move the receiver on the beanpole down 8” and this will give you the top of block elevation you need for your footing stone. It is very important to laser tone the first footing stone to make sure you are setting it just right. If you do not laser tone the first base stone you install it could be a little too high in which case you will catch yourself needing to add rock all the way across your  base course or if it is to low you will be digging rock out all the way across your base course. Both of these options are not good and will cost you a lot of time and work. It is much better to make sure that the top of that first base stone is toned perfect on every side. Once you have that tone you will not need to laser tone the other base stones since you will level each stone as you go across. However, since you have the laser level and it is set for the right elevation and you do not do this every day it may not be a bad idea to check every 4-5 stones just to make sure you are putting the stones in level. The base row will take the most time to install and it is so important to get everything just perfect. As you are placing the base stones in place it is a very good idea to have someone placing the stones in place for you while you set them. Before you begin setting the base stone, set up your string line across the straightaway to guide your stone placement to make sure you are installing the base course straight. The best way to set up your string line is to put a stake in on both sides of the straight of way then tie the string to one side and pull the string across to the other stake. Adjust this line to be about a half inch above the top face of the stone. Now you have a straight line to guide you as you install the base course to your retaining wall. To set a base stone you will need to take your level and place it across the top face of the stone making sure it is in the middle of the bubble on your level. Next check the stone face to tail on the top and make sure it is level that way. The best way to level the stone most of the time is to have the stone just a tiny bit too high and tap it down into place using your rubber mallet . After you have your first stone in place and you have toned it to make sure the elevation is correct you will use this stone as a reference point to level the next stone. Take your level and place it across the stone that you just set and the stone you are setting. Make sure the new base stone you are setting is level both side to side and face to front with the stone that has already been leveled. You will continue this process.  As you are doing your base retaining wall course you will have the person or people helping you begin to stack stone across the base stones.

STEP SEVEN:  STACKING & STRAIGHTENING THE RETAINING WALL

            The first stone stacked on each new course of stone needs to be measured to make sure it is in the center over the two base stones below it. For example, with a retaining wall block that has a face 18” wide you will measure to make sure the stone stacked on the top of the base stones is exactly 9” on each stone. When this measurement is correct on a wall that is running straight you will keep your bonds lined up. My advice at this point is to stack 3-4 rows of stone behind the person doing the footing but always making sure to stay at least two stones back so they do not lose the ability to go back and check for level. After the footing on the straight-away is completed and the wall is stacked across 1-2 rows depending on where the retaining wall engineering calls for you place your first geo-grid. now it is time to use your string to straighten each row of retaining wall block making sure that your wall is straight. The best way I have found to straighten a row of retaining wall blocks is to have one person on one side holding the string with a level or piece of wood wrapped around it to keep the string from touching the retaining wall block in any way. Have another person on the other side doing the same thing. If you only have two people tie the one side of the string to the grade stake and wrap the other side around the level or wood to keep the string from touching while the person on the other side pulls the string tight. Now that the string is set up you take your rubber mallet and go to the end of the row of retaining wall blocks you are straightening and knock out the block on the end as far as it will go. Make sure it is straight but has been pushed as far forward as it will go. After this go down to the other end of that row and do the same thing with that end block. Now your two end retaining wall blocks are out as far as they will go you look down the string and block by block knock all the stone out till the face of the retaining wall stone is in line with the string. Repeat this for every row of stone that has been stacked. Next, after the base stone is installed the rows are stacked and straightened, you will need to start backfilling behind the retaining wall blocks you have already stacked.

STEP EIGHT: BACKFILLING YOUR RETAINING WALL

            It is my advice to backfill all the way up to the top of the row of stone right below where the geo-grid is to be placed. So if the geo-grid is called for on the top of the third row in the retaining wall engineering then you will fill behind the retaining wall with 1” clean rock all the way back to the end of the geo-grid. So on a retaining wall that is 10’ exposed height of wall more than likely the geo-grid will be 7 l.f. The rock must be backfilled to the end of the geo-grid zone. On the dirt bank or behind the clean rock you will need to put filter fabric to separate the dirt backfill from the 1” clean rock.

 As you are building the retaining wall up you will keep repeating these steps over and over. You will need to install footing stepping up into the hillside as your new retaining wall returns into the hillside on each end.  If you are able to backfill from the top of wall without driving directly behind it or backfill from the front of the wall it is my recommendation to use 1” clean rock all the way up to 1’-2’ from the top of retaining wall. After the rock backfill is complete, put filter fabric over the rock to separate the clean rock in your retaining wall from the dirt that will be installed on the top of wall to top off the wall. Before we get to that however, make sure to install all your retaining wall cap on the retaining wall.

STEP NINE:  INSTALLING RETAINING WALL CAP

We like to glue our retaining wall cap and then straighten the cap using a string line. Get your cap on the wall close to being straight. Make sure you put your cap on so that they straddle the block evenly. Make sure that the first cap you put on the wall is half over one block and half over the other block. I hate it when I see retaining walls where the contractor or the homeowner installs the cap lined up with the row of retaining wall blocks below it. That does not look as nice and it is not as strong. Make sure the glue you use is a retaining wall glue. Also, if you decide to put your glue down under the cap it works best to put the glue on the back of the stone in case the retaining wall cap ever needs to be taken off for some reason at a later date. If you put the glue on the back of the retaining wall block it allows the cap to be removed more easily in an emergency but does not allow the cap to move or come off. Also, it is my recommendation that if you put the glue under the cap and then straighten the cap with a string line that you move fast before the glue sets up. In the summer time when things are hot and dry the glue will be starting to set up inside of 10-15 minutes tops. In some places you will need to saw cut the retaining wall cap with a diamond blade saw. There are many different ways to approach this so I would say to look at the recommended installation instructions from the manufacturer of the specific retaining wall system you are installing. All closed face retaining wall systems will need to at least cut some cap on the end or on the corners of your retaining wall. It is pretty simple but gets much more complicated when you are cutting in a radius around a curved wall. After the cap is glued and straightened and the needed saw cuts are made lay some filter fabric behind the retaining wall block on the top of your wall.

STEP TEN:  GRADING BEHIND THE RETAINING WALL

             If you have used 1”clean rock you will need to put filter fabric down over the clean rock to keep the dirt out of the rock. If you used 1” minus rock to backfill your retaining wall you will only have to put the filter fabric behind the top rows of retaining wall blocks that will have dirt backfill. You should have plenty of dirt still on site. As a matter of fact, one of the unforeseen problems many times is there is so much dirt generated during dig out that you may not have enough room to stockpile it. Many times we will need to haul dirt away during the excavation of the retaining wall.  There are trucking companies you can hire to take dirt away although you will need to load them with your skid loader and at times that can be kind of tricky. It is my recommendation if you are bring in a trucking company to haul dirt away, check them out with the BBB and ask for some references. Also, establish the way you will pay and the rate you will be charged. Will they charge you a set fee by the load or will they charge by the hour? One last thing about the hauling company; make sure that the truck they send out to you will not be so tall that your skid has a hard time loading it. Back to the dirt backfill.  To top off your retaining wall you will start digging into the pile of dirt that you have on site. If you have no dirt you will need to have dirt brought in.  Make sure to use fill dirt for the low parts since it is much cheaper than top soil. Anyway, you will almost definitely have more dirt than you know what to do with and start digging into that mound of dirt with your skid loader and start dumping it bucket by bucket into the area to be filled. Be sure to put your bucket down to smooth it out as you go, tracking in the dirt and compacting it with your skid-loader. Be very careful working behind the wall; do not let your wheels or tracks get too close to the wall because there is a real danger of pushing the top of your retaining wall out with the skid loader if you get too close. After the bulk of the dirt has been tracked in and smoothed out you are very close to being finished. A good clean up, some sod or seed and it will not be too long until you will be enjoying your new yard and the great accomplishment of finishing such a large retaining wall project yourself.

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