Interlocking Stone

Retaining Walls, Patios, Driveways, Front Entrances, Steps and Walkways

At M.D.S. Projects Ltd., we have several landscaping solutions, one being the use of interlocking stones for steps, driveways, walkways, retaining walls, front entrances, and patios. Interlocking stones, as the term suggests, are stones that connect in such a way that motion of any part is constrained by another. These stones give the feel and look of cobblestone pathways. The most common materials for these stones are concrete and cement.


Benefits of Interlocking Stones

Interlocking stones can be built into a variety of styles with different shapes, size, and colors. This is not always possible with natural stone where you have to settle with what Mother Nature gives you.

Although the uniqueness of natural stone has its charm, some applications require more defined shapes, sizes, and colours.

The fact that interlocking stones can be customizable to match the user’s needs means the landscaping designer has greater flexibility to exercise his/her design creativity. The flexibility you get with different design options means you can delineate pavement areas. This adds to the visual appeal of the property in a way that is not possible with rigid pavements.

Concrete pavers are generally less expensive compared to granite, clay, sandstone pavers. Their maintenance and replacement costs are also lower.

Concrete paving technology has come a long way over the past few years. Today’s pavers are extremely dense and have exceptional strength and durability. They are very stable and can withstand severe loads. The stones are indeed stronger than black asphalt and regular poured concrete surfaces which are susceptible to surface cracks.

Interlocking stones made of concrete are unaffected by extreme frost and heat. This is important given Guelph’s unforgiving weather. Each stone has joints that allow for expansion and contraction and small amounts of movement without cracking. Factory made interlocking stones can go for up to a decade.

Ease of repair is one of the greatest benefits of interlocking stones. When one stone is damaged, you simply need to pull it out and replace it with another one. This makes these stones the ideal solution in areas where you need to access what is beneath from time to time (such as a water line or sewerage). You cannot do this with concrete, stamped concrete, or asphalt. This ease of maintenance also makes interlocking stones cheaper to maintain.

Interlocking stones give you reduced albedo compared to concrete and asphalt. Concrete and asphalt absorb heat during the day and release it during the night, which creates heat islands. This, combined with stormwater runoff which is common in Guelph, gives impaired water quality and water that is abnormally warm.

You get zero-wait time with interlocking stone. You have to wait for concrete and asphalt to dry, meaning you will not have continued use of your yard.

Unlike concrete, asphalt, and even natural stone, interlocking stones are manufactured in controlled environments. This gives the stones consistency in terms of strength and quality.

The interlocking mechanism of interlocking stone makes them stable without the need for cement. Natural stone often requires cement to get the desired stability. It is, however, important to note that it is not the shape of the stones that gives them the name “interlocking” stones. It is a combination of proper installation, the technology used to make the stone, the bedding sand, the edge restraint, and the joint sand that allow the pavers to interlock.

Our Interlocking Stone Brands

At M.D.S. Projects Ltd., we get our interlocking stones from some of the top interlocking stone manufacturers in North America. This is important because even if we give workmanship guarantees, we also feel our clients deserve the best in terms of the materials used. Top manufacturers have quality products and they offer good manufacturer warranties. Our suppliers include:

Unilock® has a big selection of interlocking paving stones that are available in different styles. The different options all have unique characteristics, meaning there is something for everyone. The different options range from stones that have a contemporary design for a modern appearance to those that resemble old-world clay bricks or cobblestones.

Unilock® has been around for over 40 years. It came into existence when the founder, Ed Bryant, came across Uni-Stone, a revolutionary European paving method. Ed then licensed the product and bought a basic paver machine – that is how the concept found itself in North America.

Interlocking stones from Unilock® are manufactured using the company’s advanced technologies. These are:

  • EasyClean™ Stain Resistance: These technologies fortifies pavers. The stones made using this technology are ideal for pool decks and patios because they can be easily cleaned following a spill before stains can develop.
  • Ultima™ Concrete Technology: This is a proprietary manufacturing process that produces stones whose strength is up to 4 times that of poured concrete. Stones made this way are ideal for high traffic areas.
  • ColorFusion™ Technology: This technology disperses color randomly to give interlocking stones the look and feel of natural stones.
  • Reala™ Technology: This technology produces interlocking stones that have a realistic texture of natural stones, cobblestones, and bricks.
  • EnduraColor Plus Architectural Finishes: The technology gives everlasting beauty by utilizing proprietary blends of some of the highest performing minerals in nature such as quartz and granite.

Unilock® has several design assistant tools to help landscapers come up with the best designs. These include Uvision 3D Landscape Creator which allows landscapers to create 3D models of the yards they are working on and Uvision Mix and Match which allows landscapers to explore paver combinations. The company also has a Unilock Design Idea Catalog which has photos of real-life projects for inspiration.

Unilock® offers a lifetime guarantee on the structural integrity of its interlocking stones – the first North American paver manufacturer to offer such a guarantee. This means all materials that are installed and maintained according to the company’s guidelines and that are subjected to normal tear and wear will be replaced at no cost to you should they become defective. This lifetime guarantee is transferable, meaning the next homeowner will be covered.

You must register within 60 days after the purchase to qualify for the warranty. Note the company does not guarantee color matching and replacement labor is not included. Hiring us ensures you get the color right the first time around.

We are a Unilock® Authorized Contractor and we are authorized to provide FREE estimates. The company vets all contractors before they can become Unilock Authorized Contractor, which is proof we have what it takes to do a good job. Hiring a Unilock Authorized Contractor is important because the manufacturer’s warranty will not be void in the unlikely event of failure on the part of the material.

We are proud to partner with Unilock because it abides by CSA, ASTM, and European organizations. You can learn more about the company by calling 1-800-UNILOCK or emailing

Techo-Bloc was founded and is still run by Charles Ciccarello. He got the inspiration to start manufacturing interlocking stones from his father who was a landscaper. The company’s landscaping background allows it to anticipate customer needs even if is manufacturing interlocking stones. The company has grown to have over 700 stores in the U.S. and Canada.

Techo-Bloc pavers are referred to as “interlocking concrete stones” not because they have an interlocking shape, but because the stones, combined with the joint sand, bedding sand, and edge restraint make them immovable.

Techo-Bloc offers a transferable lifetime warranty on the structural integrity of its dry-cast retaining wall stones and paving stones (apart from the company’s Stonedge™ collection warranty is offered to the original Consumer Purchaser/homeowner only). The warranty covers all decomposition and/or disintegration resulting from natural tear and wear, provided the stones are properly installed and maintained, as well as abnormal deterioration of surfaces resulting from the use of sodium chloride (such as de-icing salt). All dry-cast concrete products used for institutional, industrial or commercial purposes also come with a lifetime warranty.

All products from Techo-Bloc comply with Canadian Standards Association (CSA) and the American Society for Testing and Materials (ASTM) standards.

All pavers from Techo-Bloc are made to withstand high traffic, including vehicular traffic. They are also color-consistent and salt-resistant. The interlocking stones are also characterized by superior thickness.

The company provides Installation Guides, which provide information on the proper installation methods of slabs, pavers, permeable pavers, steps and caps, walls, pool coping, edges, and other products. These guides are available for download on the company’s website. We follow these guides when installing and repairing interlocking stones to prevent the voiding of the manufacturer warranty.

We prefer locally made interlocking stones because we are able to track their origin and the manufacturing process being employed. We are big on reducing our carbon footprint and we are able to achieve this with local manufacturers since the distance the stones have to be transported is short.

You can call the Techo-Bloc head office at 1.877.832.4625 or fill the online form for answers to any question you may have on their products.

Permacon Group, a division of Oldcastle Building Products Canada, Inc., is a leading concrete paver manufacturer that makes interlocking stones for walkways, pathways, patios, terraces, and garage entrances. The company makes interlocking stones in a wide variety of models and hues. The company also makes slabs, the major difference between slabs and pavers being that pavers are at least 60 mm in thickness while slabs can be thinner.

Permacon offers manufacturer warranty on all its products that are made for residential use only, leave for Be.On Stone products, Permapro products, and Hemmingford products. The warranty guarantees that the concrete products delivered will be free from manufacturing defects on the day of the delivery. It further guarantees that all its products meet or exceed Canadian Standards Association (CSA), Bureau de Normalisation du Québec (B.N.Q.) and American Standards for Testing Materials (ASTM) standards.

The company also guarantees that the products, provided they meet the other conditions, will have structural integrity for a period of 50 days from the date of the purchase. The interlocking stones must have been used for normal non-abrasive work. The warranty also covers abnormal deterioration resulting from the use of sodium chloride such as during the de-icing. The warranty means you can return defective products within the 50 days for a replacement of the same.

Note that the warranty does not cover spalling or other types of breakages that are as a result of abrasion, overstressing or impact. You will also not be compensated if the deterioration is as a result of poor design or installation of the landscape or where applicable codes, recognized work procedures, and standards are not followed. This is the main reason you should always hire a professional for landscape design and interlocking stone installation. Acts of God, negligence on the part of the customer, the installer, and the building owner and damage by snow removal equipment are also not covered.

To redeem the warranty, you will need to present proof of purchase (the invoice, Permacon product identification sticker, or delivery slips) and you will be given the replacement product free of charge. Re-installation costs are your responsibility. The warranty is transferable.

The warranty is transferable to the current owner or to any subsequent owner of the building or the job, on condition that it is accompanied by a valid proof of purchase.

Permacon has been in business for over 60 years, having been founded in 1952 in Quebec. The company, which was originally called Bloc Vibré inc. before merging with Les Industries Fortier Ltée to form the Permacon Group, prides itself as a pioneer, champion of growth, and innovator in the Canadian concrete products industry. The company, which recently merged with Oldcastle Architectural, an industry leader in the manufacture of concrete landscaping and masonry products, has an offering of over 1,000 landscaping and masonry products for residential, commercial, institutional, and industrial environments. The company has 12 plants and it employs over 800 employees in its Ontario and Quebec facilities.

Our Interlocking Stone Installation Process


For you to reap the benefits of interlocking stones, you have to install them properly. It is a common temptation to do DIY landscaping, but you should leave the work to a pro to prevent voiding the manufacturer warranties, to get workmanship guarantees, for safety reasons, and for convenience. You actually save money when you hire a pro since this means you do not have to buy the tools, equipment, and safety gear needed for the job.

1. Once you contact us, one of our experts will pay you an on-site visit, a service we provide FREE of charge. The purpose of this visit is to get the scope of the project. Some of the things to consider during the planning phase are drainage, neighborhood bylaws, and house décor. There should be a slope away from the home, the desirable slope being 1/8 inch per foot. This ensures water does not stagnate, or worse, enter your home. Consider the specific use of each area to know the best landscaping material to use. As an example, a garden requires different materials from high traffic walkway.

2. The next step is marking the ground where the interlocking stones will be laid. We mark the area off with wood planks, stakes, and strings, spray paint, or other material to get a feel of the size and to gauge how different shapes fit into each other. We measure the project dimensions to help in the calculation of the materials required. We also observe how the sun hits the spot and determine areas that have shade where we could place such things as benches.

3. The next step is picking the interlocking stones and other materials. You could pick the stones yourself, but we advise you to pick from one of our suppliers because we have vetted them and know they have quality products. We are authorized contractors for these suppliers which ensures that your manufacturer warranty will not be void. We will include the materials in our quote, detailing each and every unit, if you give us the go-ahead. You will have many choices to make at this step, but our landscape designer will guide you throughout the process.

4. We will then order the materials. Once we receive them, we will move to the site with the necessary tools and equipment. Some of the tools and equipment needed for interlocking stone installation include vibrating plate compactors, masonry saw or splitter, shovels, brooms, grading rakes, rubber mallets, concrete sand, hand level, and stakes and strings, among others. We have all the tools and equipment needed for the job and we guarantee you that we will not subcontract any part of the job.

5. Once the area has been marked and all the materials are in place, the next step is excavation. The base is the foundation and a lot of care has to be put here. We excavate all loose and otherwise unstable soil until we reach solid, compact earth. The depth depends on the intended use. As an example, we do 4 to 6 inches for areas where there will be pedestrian traffic and 7 to 9 inches for areas that will have vehicle traffic.

6. The excavated area is then filled with gravel and the gravel is compacted. We use ¾ inch crushed aggregate for the gravel and we use the plate compactor between layers. We add the gravel until we have reached the required base depth. We sometimes add a light mist of water to aid the compaction process.

7. High Performance Bending (HPB) stone is then added and leveled using a leveling bar. We then put a restraining wall around the area to be paved to keep the stones from shifting and moving as we install and as you use them. These could be concrete blocks that match the interlocking stones, the side of your home, and any type of special edging.

8. The next step is laying the interlocking stones on the prepared surface. We usually stretch strings across the base to ensure that the pavers are straight and they maintain the right pattern. When placing the stones, we either start in a 90-degree-angle corner or along the stretched string – each landscape contractor has his/her own technique. We ensure that the gravel is not disturbed during this process.

9. Next, we run the light layer of sand and then run over it with the vibrating plate compactor so that it settles between the gaps. The stones will be immovable after this step. This is where the term “interlock” comes from.


10. The interlocking process is completed with more sand. We use high-performance polymeric paving sand (jointing sand) for this. You can choose between sands of different colors to complement your design ideas. We apply the sand to cover every crevice and crack. From our experience, simply dumping the sand on top of the area and spreading it with a broom until the joints are full will not give you the desired results.

11. Finally, the surface is misted with water, which activates a hardened seal (to prevent weed growth). An alternative to this step is applying a sealant on the joints. Sealing the interlocking stones is an option, but highly advisable. Sealants are important in preventing weed growth and oils between the stones, which reduce their lifespan. Sealants also boost the color and help keep the polymeric paving sand in place. You may need to reseal the stones every few years, depending on the sealant you choose. You have the choice of epoxy (urethane-based product) or an acrylic-resin product.

We also will clean up once the entire project is done. This process is not rocket science, but it is very involving and unless you have a few weeks to spare, it is a daunting task. You need to get the necessary permits, to source for materials, tools, and equipment, to prepare and lay the stones, to do the rest of the landscaping, and to clean up.


We are available on 519-827-7057 and for all your Guelph landscape design and construction needs.

Additional Interlocking Stone Information