Interlocking Paving Stones: A 10-Step Installation Guide

Interlocking Paving Stones: A 10-Step Installation Guide

interlocking paving stones installation guide

Paving stones provide a beautiful, strong and long-lasting surface as a means to enhance outdoor living and create more space for you to enjoy the sunshine, shade and breezes of nice days.
People like to be outside to visit, play, eat, drink, cook, read and relax, among other things, and interlocking paving stone can make the perfect outdoor oasis as well as a tough driveway or parking area.

You can arrange the stones however you like to make the ultimate outdoor living room with a fireplace, a pool area, a modern-design driveway and more.
Additionally, a well-done design adds curb appeal, freshens the look of your home and increases your living space. You might be an ambitious and talented do-it-yourselfer who can tackle the project, or you may prefer to call in the experts.

However, if you do end up completing the project yourself, there are some steps to take so you start the process prepared and finish with a good result. The first thing you need to know about is the benefits of interlocking paving stones. They can:

interlocking pavers strength

• Gain compressive strength of 8,000 pounds per square inch (psi) — poured or preset concrete nets 4,000 to 5,000 psi.
• Achieve minimum water absorption.
• Meet freeze-thaw standards of frigid climates.
• Get better cold-weather durability than asphalt.
• Have no requirement for expansion joints.
• Withstand high human or vehicle traffic.
• Be easily replaced with a matching paver.
• Come in an array of colors, shapes and textures.
• Create symmetry, patterns or a creative design
• Have materials that meet or exceed industry standards
• Enjoy a long life since pavers last for 20-25 years
• Accomplish sustainability with permeable pavers

Installing paving stones is possible if you follow the steps and invest time and care into each one. You can hardly be too careful when you measure, draw, plan, obtain prices and then get to work on the project because each stage lays a base for the next. How to install paving stones is step by step — slowly and with care.

pavers last for 20-25 years

Step 1: Plan the Project

First, establish a general idea of how large an area you will create and where you want it to be. Good drainage from the area is essential, so you will want to examine how water runs to and from the area when it rains and avoid any places that often flood or have standing water after heavy rains.

Generally, you want the land to slope slightly down and away from the areas you plan to use, like homes and yards are usually situated. The standard amount of desired slope is 1/8 inch per foot, which is usually about what you’ll find around your home and what you’ll want for the newly created space.

You can mark the area off with spray paint, stakes and strings, wood planks or other material — just to get a feel for the size you need and/or if a certain shape will fit. Take some measurements and think about what the paver area will abut and what is around it. Observe how the sun hits the spot, and your preference might be to put the area in the shade, sun or a location that gets both.

Define your new outside area by placing stakes every few inches and putting string around them, taking care to allow a few extra inches all the way around for the restraint and edge materials. If your project has a pattern or design that requires centering or special alignment, use stakes on the edge with a low string between them to mark points from which you can work and stay on track. You can also carefully use chalk-coated string to mark lines on the top of the sand bed for alignment guidance.

In order to calculate the amount of sand and gravel you will need, measure the project dimensions including length, width and depth. It is possible to calculate the amounts yourself with the help of industry guidelines, or your vendor or contractor can help figure out how many cubic yards are needed for your paving-stones installation.

Step 2: Pick the Pavers

pedestrian and vehicle traffic areas thickness

You will encounter a broad range of choices when you begin looking at interlocking pavers, which are available in an uncountable number of colors, patterns, shapes, sizes and thicknesses. Typically, the standard thickness for an area with pedestrian and average vehicle traffic is 2 3/8 inches.

The array includes tumbled pavers that have rough edges and look like stone or slate. There are also bush-hammered and shot-blasted interlocking pavers, which have a textured, stone-like finish. Ground pavers resemble stone, but they are smooth like marble or granite.
Nearly any design and style imaginable can be created with the interlocking concrete pavers.

Step 3: Gather the Materials

You will need a number of basic materials for paving stone installation:
• Masonry saw or splitter to trim
• Vibrating plate compactor to settle
• Shovels to put in base material
• Brooms to spread and sweep sand
• Grading rake to even out the base material
• Rubber mallet to adjust the pavers snugly into place
• Enough concrete sand to accommodate your project
• Wooden 2×4 and 1-inch pipe to screen the sand
• Enough pavers to cover your area plus some extras for error allowance
• Stakes and string
• Hand level

Step 4: Dig the Base

A crucial part of installing paving stones is proper preparation of the base since it is literally the foundation for your new patio, living area or driveway. Because it involves excavation of several inches, you’ll want to be sure and call your local or state utility-dig line a few days before you’re ready to start. That way, you can have the utilities marked and make sure you don’t hit anything important.

Preparing a good base requires the excavation of any loose or otherwise unstable soil down to the solid, compacted earth. How deep you need to dig depends on the combined thicknesses of the gravel base, sand layer and your pavers, which vary — as does how you will use the area.

For example, the recommendations are to provide a base of gravel 4-6 inches thick for average pedestrian traffic, which requires you to dig about 7-9 inches deep. For vehicle traffic and around swimming pools, the gravel base should be 6-8 inches deep — with even a few more inches if you plan to park or drive an extra-heavy vehicle on the surface, such as a recreational camper or an 18-wheeled truck.

The most common advice on gravel size for the base is 3/4-inch crushed aggregate. You will need to use the plate compactor between layers of the gravel so it becomes compacted into place. Keep adding gravel and compacting until you reach the desired base depth. It can help with the compaction process to slightly wet the gravel — not a soaking but a light mist.

Step 5: Bring in the Sand

You need a sand base no thicker than 1.5 inches for your paving-stones installation, and it helps to make sure you use a quality bedding sand. The Interlocking Concrete Pavement Institute gives specifications for the standard of sand to use in a paver setting bed:
• ASTM C33 and CSA A23.1
• ASTM C-144 and CSA 179 graded mason’s sand is an accepted alternative.

ASTM stands for the American Society for Testing and Materials, and CSA stands for calcium sulphoaluminate.

Sand quality matters a lot because it is made with different particle contents for various projects. Some contractors would use the same sand to fill the joints as they used to bed the interlocking paving stones. Other people want to use the material specifically mixed to fill the joints and cracks of a paver project.

As you pour in sand for the base, use the rake, pipe and 2×4 to work it into the spaces — and any combination of things to even it out. A “screed rail” is a tool used to level out concrete or sand. This tool varies in design but is basically a heavy piece affixed to some kind of accessory that drags it across a surface to make the surface even. You can buy or sometimes rent screed rails, which typically come in 16-foot, 9-inch sections that can then be trimmed to fit.

Tools are important because it is your goal to cultivate a perfectly even and smooth surface for the sand base of your interlocking pavers. Depending on the size of your area, you might want to work in sections. While hardly anything is perfect, you can strive for it because the sand is where your pavers will rest.

If the sand is uneven, the pavers will be, too, and rocks or divots in the sand will prevent the pavers from seating properly. Use a level to ensure a quality surface that is even and smooth. To check your sand bed, gently place the wooden 2×4 down on its broad edge and then put the level on top of that. Once the sand is perfectly level, take care not to allow anyone to step on it. Additionally, be prepared to lay the pavers within a day’s time so the integrity of the sand bed remains true.

6. Ready the Restraint

Plan to have a restraining wall of sorts all the way around the area where you lay pavers in order to keep them from moving and shifting as you install and use them. The restraint could be concrete blocks that match the pavers, the side of your home or special edging that you secure with ground spikes.

If you use your home or the molded edging with spikes, the restraint can be put into place before the pavers. However, if you use concrete restraints, place them after most of the pavers are laid but before you put the edge piece in place. Concrete restraints are usually tacked with wet-set concrete.

You’ll see when you get close to the edges that some trimming will be necessary in order to fit the end pavers in, and this can be done with either a masonry saw, which is the most precise tool, or a masonry splitter. The goal with trim is to fit the final piece in as snugly as possible and to try not to leave any rough cutting edges that will show.

7. Place the Pavers

Depending on the design and pattern you chose, it might be necessary to stretch strings across the sand base to keep the pavers straight and maintain the correct pattern. Once you’re ready, begin placing pavers either starting in a 90-degree-angle corner and/or according to the string you stretched across the space. Some people will draw out a paper or cardboard guide to remind them of the sequence needed to create the pattern, design or look they seek.

It is important when placing the paver to gently set it into place evenly and without disturbing the sand with extra vertical or horizontal motion. Often the best method for installation is to hold the paver between two hands, and then get it into exact position before you lower it into place. A slight slide to one side or the other won’t be as detrimental as angling the stone into place since you’re trying to maintain that perfectly flat sand base you created.

Pavers should feel tight by hand but will have a built-in space between them about 1/16 of an inch to 3/16 of an inch wide, and that is normal. People commonly lay the pavers in rows, but you can work the “field” nearly any way as long as you’re consistent and don’t disturb the sand other than to set the pavers into place.

pavers should be tight

8. Compact the Field

Once you have all your pavers and restraints in place, put down a light layer of sand, and then run over it one time with the vibrating plate compactor — which you can rent from many kinds of equipment shops. This stage creates the initial part of the “interlock” of interlocking stone pavers. During this first step, sand will begin to settle into place as well as get squished up between the pavers.

9. Sand Finale

Complete the interlock process with more sand — high-performance polymeric paving sand, also known as joint sand for use in the joints of such installations as interlocking concrete pavers. The sand comes in different colors to complement many styles and design ideas.

The goal with this application of sand is to fill every crack and crevice. You can just dump the sand on top of the new area, and then spread it around with the brooms until all the joints are full of it. It is preferable to sweep away the excess as opposed to using a leaf blower for example, which might blow away sand from in the cracks and crevices.

10. Seal the Pavers

It is optional but advisable to seal your interlocking stone pavers following installation. Sealant helps the pavers resist stains from environmental components, such as oils and weed growth. A sealant also boosts the color, and it is another aid to hold the joint sand in place. You will have to reseal the pavers every few years depending on the type of sealant you use.

If you seal with an epoxy- or urethane-based product, expected life span is probably 5-10 years. If you seal with an acrylic-resin product, expected lasting power is about 1-3 years.

One factor to be aware of before you seal is the natural efflorescence of stone pavers. It will look to you like chalky, dusty residue and is a naturally occurring substance that should be removed before sealant is applied. Some people will wait a few weeks and let it wear off naturally then seal the pavers, while others will sweep and lightly spray the surface to remove the efflorescence.

Consult a Professional When Needed

Expertise makes a world of difference in masonry and concrete work, and we enjoy helping people find the right pavers or other outdoor treatments to suit them, their environment and the use they envision.

Nitterhouse Masonry Products is a family-owned business that began in 1923 when a single mason started honing his expertise and making quality concrete blocks in his garage. Our professionals have many specialty certifications, including for interlocking stone installation.
To create an ideal outdoor space, you’ll need knowledge in everything from materials, setting and sealing to vision, layout and style. Contact us anytime you need a professional partner for a patio, walkway, driveway, retaining wall or other type of outdoor area.