A Patio Slabs Guide

If you are looking for a relatively inexpensive and easy to install material for your new patio, patio slabs, also known as paving flags, may be just the ticket. In this guide, I hope to give you some of the basic information you’ll need to know when thinking about your next outdoor project using this material. If you have any questions, leave them in the comments.

The advantages of patio slabs are quite obvious – you enjoy the benefits of concrete (strength and durability) while not sacrificing much in terms of money for their installation and upkeep. The disadvantages, aside from aesthetics (how they look) are relatively few; for example, the large sizes may crack due to freeze-thaw cycles if they are not properly set on the subbase. The larger the slabs, the more likely they are to crack when the ground freezes and thaws, so keep this in mind when picking the size and shape of the patio slab for your next project. A few more disadvantages are mentioned below.

It should be noted that you can use these patio slabs on any other area in your house. Though we call them patio paving slabs, they can use for driveways, walkways, pool decks, gardens, and more. Garden paving slabs, for instance, are a great material to add to your landscape/hardscape partnership. In this article, we simply restrict ourselves to discussing their benefits for patios.

Types of Patio Slabs

Patio slabs are generally rectangular or square in shape, though other shapes may be available, such as circular and irregularly shaped. In general, if you are installing the slabs yourself, it’s best to go with the rectangular or square shapes, because they are the easiest to work with and install. The circular and irregular shapes are often used for stepping stone walkways and other more “natural” looking projects.

There are two ways to obtain patio slabs. The first is to simply buy them preformed or pre-made. This is relatively cheap, while also  easy to install, though you’ll be limited in the shapes that you have given the one kind you buy. The second way to get the slabs is to pour them with fresh concrete. With this method, they can be made on the job as needed. This provides you with custom slabs that you can use for your patio, so you won’t be boxed in to the ‘standard’ sizes.

Patio slabs come in many different kinds, sizes, shapes. In this article, we will focus mostly on the concrete variety. However, you can get slabs and many other materials. Natural stone is quite popular, while also being quite expensive. Examples of natural stone slabs include sandstone, granite, slate, and limestone.

Disadvantages of Slabs for Patios

There are few disadvantages of this material to be aware of. First, if you get in the regular concrete variety, they can be rather boring. They are gray and rather drab, so the are more utilitarian approach to creating your patio. If you pick natural stone, or at least colored concrete and other fancier varieties, expect to pay more for your material.

In addition, it may be very difficult to cut concrete paving slabs into the specific shape you want, so you may be relatively limited in the design options at your disposal. Pavers, on the other hand, can be cut and arranged in a variety of shapes and patterns. However, what you lack in design options will be made up for in the ease of installation of this material, and if you’re on a budget, you probably shouldn’t expect much in the way of luxury for your patio material anyway.

Finally, this material is relatively heavy compared to other materials if you get purchase them preformed. Thus, you may have to pay a high delivery charge if you cannot pick them up yourself. In addition, their heavy weight may make them difficult to deal with if you are installing them yourself, so be careful when working with the material.

How Much do Patio Slabs Cost?

One of the benefits of patio slabs (at least the preformed variety) is their relative inexpensiveness when compared to pavers and natural stone, such as travertine. This is because they come fully formed and ready to lay, so no pouring will be necessary. Pouring patio slabs isn’t that expensive either – it just requires some skills or the services of a contractor, which may up the price of the project. In addition, there relatively inexpensive to install, because there are fewer slabs to lay that if you had to lay the equivalent number of concrete pavers. Even though the price is lower, you’ll still enjoy many of the same benefits as paving stones, such as their ability to resist freeze/thaw cycles, while also enjoying the ease of installation and relatively lower price when compared to both poured concrete and pavers.

In general, expect to pay anywhere from $2 to $5 per square foot for the material and installation of the material – less if you are doing the work yourself. It will depend on the type of slab the purchase as well of any finishing and other tasks that need to be done to complete the work. Obviously, you will pay much more for natural stone and decorative kinds of concrete slabs.

Installing Patio Slabs

Concrete patio slabs lie in between poured concrete and concrete pavers on the scale of hardscape materials. Thus they combine both the virtues and drawbacks of each type of material – ultimately depending on whether you get the ‘pre-formed’ slabs or pour them yourself.

One of the great advantages of this material, however, is that it is relatively easy to install yourself regardless of the method you choose. Concrete pavers and paving stones have certain learning curve to them, as does poured concrete and hot asphalt. However, concrete slabs and their ilk are very forgiving to newbies. If you make a mistake, you can often simply just pick up and replace the offending slab. This may not be so true if you are using mortar and grouting to lay your slats, which is why I often suggest people to use a sand base just like you’d use for concrete pavers.

Of course, as with any hardscape installation, having a good subbase is critical to the lifetime survival of the project above. Make sure you have enough aggregate base below that has been compacted properly and is at an appropriate thickness, usually around 6 to 8 inches.

Once your base is ready, laying patio slabs is quite simple. Simply put them in the pattern or arrangement that you like, making sure that they are properly lined up with house other straight-line features of your landscape and home. In addition, make sure that your grades are correct, as you do not want any water flowing into your basement or other sensitive low-lying areas.

In fact, installing patio slabs much like installing concrete pavers, so for more detailed information on how to set up your project and do the work correctly, check out the installation section of this website. If you do end up hiring a contractor, and want more advice on how to secure the best one, check out this discussion on how to hire the best paver contractors – much of the same advice applies here.

If you want to know more specific details on how to lay patio paving slabs, contact a local contractor or home improvement store for more information. Or you could just leave some questions in the comments below!

How to Save Money on Patio Slabs

Since concrete is a popular material, it should be relatively easy to find cheap patio slabs. One way is to simply use reclaimed patio slabs that other homeowners have decided to get rid of. You can often find advertisements in online classified ad sites, like Craigslist, where homeowners will be advertising that they have slabs available for anyone who wants them. Often you can get them for free, as long as you come and pick them up yourself. Thus, if you’re looking for lowest prices possible for your materials, finding them in the secondary market is probably your best bet.

The usual way to get cheap paving slabs, if this above method doesn’t work, is to look at local home improvement stores and mason supply yards for patio slabs for sale. Obviously, you’ll want to shop around to find the best deal available. If you can buy them in the off-season, that is, in the fall and winter, you’re likely to get a better deal, so preparing ahead is probably the best way to make sure you save the most money possible.

Perhaps one of the cheapest ways, but most time-consuming, is making your own patio slabs out of fresh concrete. You’ll need to create the concrete patio molds and forms required to shape the slabs into whatever size you like. Once you do this, simply pour the concrete to fill the forms. If you don’t have much experience creating your own concrete, it’s best to do a little practicing first. Another thing you can do is pour the whole concrete patio as if you were doing a solid slab – you can then use boards or other materials to “cut” the larger slab into smaller pieces. Be careful with this method, though, because inexperience could get you into trouble if the job goes wrong.

A Concrete Patio Cost Estimate

One of the classic things to install at your home is a concrete patio. This is a popular option because of the concrete patio is strong, durable, and relatively inexpensive to install. If you are beginning your research process, you’re probably wondering about the concrete patio cost. This article cannot substitute for proper estimator working on your job, but it will give you some guidance as to what the price may be, as well factors that could affect the final price.

Factors That Affect Patio Cost

Obviously, one of the main benefits of the concrete patio and the reason why many homeowners install one is its price. Concrete patios are cheap options when compared to brick, concrete pavers, stone, tile, and other hardscape solutions. However, you don’t want to go with bargain basement concrete, as you’ll have to deal with horrible cracks and other damage in the long run. Thus, make sure you’re getting a good deal, but don’t immediately go with the bargain option. Going for the contractor with the lowest bid is the quickest way to ensure that you’ll have to get the patio reinstalled in a few short years.

There are number of factors that contribute to the overall price of the concrete. The first is, of course, the price of the concrete itself. In addition, there will be other materials that may need to be added to the concrete in order to reinforce it or make it look nice. For instance, wire mesh or rebar might have to be added to ensure that cracks don’t grow too large. In addition, some preparatory work on the foundation or subbase of your new patio may need to be done. The extent of this preparatory work will obviously depend on the particularities of your project. You also have to pay for the molds and forms that may be necessary to create your patio.

In addition, there are other specific factors that may affect the final price. For example, the location of your home, i.e. the standard of living in your area will obviously affect the final cost. To put it simply, contractors in richer areas will just charge more for the same type of work than contractors in a less expensive area. Other minor factors include the time of the year, commodity costs, and the particularities associated with different contractors. Note that a smaller area of your patio will usually cost more per square foot than if your project was a larger area, so it may pay to get multiple places poured or to enlarge the size of your patio, if desired.

All the above deals primarily with poured option. However, it is possible to get large concrete slabs brought into your home and laid like papers. This option will generally be cheaper, as you won’t have to deal with wet concrete, molds, forms, and other aspects of the installation that are somewhat time-consuming and expensive.

The downside to a concrete patio, however, is that it is somewhat boring to look at. The gray and drab concrete certainly does go with most house designs, but it is not the most ideal hardscape solution in most situations. However, for those who want concrete for its cheap price but don’t mind spending a little bit more to improve the look of patio, there are few options available, which will be discussed in the following section.

Other Kinds of Concrete Patios and Their Costs

There many other ideas you can use to spruce up your backyard patio without having to go with more expensive options like pavers and natural stone. For example, it is possible to get stamped concrete patio. This will allow you to create many different designs, such as the appearance of bricks, in your patio without having to actually get paver materials and other expensive options. However, the stamped concrete patio cost will be higher than a that of a typical concrete patio.

Another option at your disposal is to go with a colored concrete patio. You can either do this by having the color mixed into the wet concrete before it’s poured, or by using concrete stainer to color the surface of the patio. Both of these options will incur a slightly increased expense, but it could make your patio quite unique compared to the typical look.

Don’t forget as well that there may be other costs associated with your patio, such as maintenance and upkeep. (See a discussion of concrete patio repair here.) You may also want to get accessories for your new patio, such as a new set of furniture or patio enclosure. For discussion of some outdoor patio ideas and enclosed patio, see these articles that are linked here.

The Verdict

So how much does a concrete patio cost in the final analysis? Obviously, we can only give a rough estimate due to the many different factors at play we comes down to getting estimate. Thus, it’s best if you contact up to three contractors in order to get a proper estimate done for your job.

In general you should expect to pay anywhere from $2.50-$5 per square foot for plain, typical concrete, depending on how complex the job turns out to be. If you begin to get stamped variations, you’ll be in the range of $5-$10 per square foot. As you get more complex, with special designs, stamps, and colors, you’ll be in the range of $10-$15 per square foot and maybe even higher, and at this point it will pay to look into the paving stones option, such as a concrete patio pavers, unless you are dead set on a concrete patio for some reason.

It should be known that the price of concrete is increasing constantly, so you may not get the deal that you got a few years ago any more. Most people will have to settle with the job costing within the four figure region, most often between 2000 and $5000.

Concrete Patio Repair Methods

Concrete patios are ubiquitous due to their low maintenance and low cost. However, they also can get damaged and cracked over time, forcing homeowners to either fix the problem or install a new patio. The homeowner who wants to save money should obviously go with the first choice, but what concrete patio repair options are available? And how will the finished product look when compared to the original installation? Though you can hire contractors to do this work, it can be a easy DIY project for you to complete by yourself. Here is what you need to know about concrete slab repair:

Fixing Cracks in Concrete Patios

If you ever detect a problem with your patio, you need to jump on it immediately. Leaving it be will only make the problem worse. This is especially true with cracks, which may get wider over time.

The most common problem you’ll see in a slab is a crack. This will develop for a number of reasons, but the most common is due to freeze/thaw cycles. Water underneath the slab freezes and thaws; this action puts stress on the slab, leading to cracks and breaks. Even if rebar or wire mesh is put in the concrete, it may still crack, especially if you live in an especially cold environment.

The first thing you need to do is ‘diagnose’ the crack – how long, wide, and deep is it. If it is narrow and shallow, it is a “hairline” crack; if it is deep and wide, it a regular crack. The qualities of the damage will affect the kinds of repairs you’ll have to do.

You may also find that the surface of the patio is covered with webs of hairline cracks and other deformities. In this case, you’ll want to get resurfacing products that will create a new, thin layer on top of the concrete that will fill in and disguise the cracking.

Concrete Repair Products

Next, you need to choose what kind of product you’ll use to fill in the crack. Your choice will depend on the properties of the crack discussed above. There are two main kinds. The first is essentially remaking concrete without aggregate. This is a combination of Portland cement and sand which will create a liquid “crack filler” that you can use to fill in the crack. If the crack is relatively thin, you can also try using ‘epoxy’ fillers. If the crack is very wide, you may have to add aggregate to your Portland cement and sand mixture. Essentially, this would be putting fresh concrete into the crack.

You can also get concrete patching mix which can be used for flaking and more widespread damage. Check your local home improvement store for products that fit your need and budget.

Preparing for Concrete Floor Repair

Before attempting any repairs, make sure the surface of the patio, and the crack itself, is clear of any large or small debris – rocks, dirt, loose concrete, etc. Brush away any debris from the crack, and use a hose or pressure washer to clean and wet the crack thoroughly.

You may want to do some more prep work on the crack itself to help increase its adhesion to the new concrete patch. Use concrete adhesive or phosphoric acid to do this, especially for narrower cracks.

Using the Portland Cement and Sand Mixture

Make and use this mixture if the crack is thin (hairline), as the mixture will seep in to the area and help rebind the crack.

However, if the crack is very wide, you’ll have to add aggregate to help fill in the space and keep the newly filled area strong.

Before filling in a large crack, you may have to ‘undercut’ it, e.g. make it bigger at the bottom of the crack. This ensures that the repair will be most effective. To do this, simply use a hammer and chisel and remove some of the concrete near the bottom of the crack; the crack should then be wider at its base than the top. Then, when the concrete pours in, the repair will hold up better with the wider, stronger base.

Using Epoxy Filler

Use this product if the crack is one inch wide or less; it should also not be very deep. The color of the epoxy is usually grey to help match the cement. It is delivered in a caulkin tube; you’ll have to use a caulking gun to apply it to the needed areas.

When filling the crack with any material, make sure to fill the bottom first. Fill the crack to the brim, and then remove any excess, leveling off the patch in the process. Let it cure before walking on the area. Epoxy doesn’t need to be finished in any way, but you’ll want to cover the repaired area for up to five days. Wet the area every day as well during the curing process.

What About Other Damage?

Though cracks are the most common, there are other types of damages to patios as well. For example, holes and depressions may develop in the surface of the project. You can use many of the same products and techniques for these problems as with cracks – in a sense, treat them as very wide, short cracks.

However, some other problems may be more cosmetic and widespread than simply functional and limited. For instance, the surface of your concrete may begin to wear and look rough; this can bother you on an aesthetic level. One way to remedy this problem is to resurface the structure. You could also use concrete patio paint or finishes to give the surface a new face; if you want to get really aggressive, consider adding outdoor patio tile or thin pavers over concrete. There are many options available to you; the ones you select will depend on how you want the patio to look, how long you want it to last, your budget, and your tastes.

Note as well that you should seal your patio to help keep it smooth and in good shape for a longer period. It will prevent stains from setting in to the surface, which can be hard to remove, and can protect it from water and the elements. Buy a good concrete sealer and apply it as directed on the packaging.

Note that fixing this crack will not prevent further cracks from forming. You may have to consider installing a new patio type if you can’t control the cracking. You could consider using patio pavers, for example, to have a project that will resist freeze/thaw cycles.

The Verdict

Concrete patio repair is definitely feasible for many homeowners, especially if the damage is minimal. However, if the damage is severe or extensive, you may want to hire a contractor. If the job is done poorly, it may look worse than the crack did.

Pavers Over Concrete: Can It Be Done?

Many people want to install pavers over concrete. Perhaps they have an old installation built on a concrete slab, or perhaps they want to avoid doing the work necessary to rip up an old concrete patio or driveway. Installing a base of aggregate may be the best option, but perhaps the best is not needed in this situation. A consumer or contractor may ask: can laying pavers over concrete be a good idea?

Yes, But…The Disadvantages

In short, yes, it is possible, but with a few things to keep in mind. First, having a pre-set base like concrete will restrict your creativity and freedom to add to the patio, driveway, or walkway. With an aggregate base, you have the ability to create new patterns or shapes; this is not the case if you are installing pavers over concrete. Ultimately, whether or not laying pavers on top of the pre-existing slab will depend on the project type itself. Laying pavers over a concrete patio may work fine, since it will experience little stress, but a driveway constructed in this way may not be able to stand the stresses of vehicles.

Grades and Heights

Second, the height of the installation will obviously be higher than it was. For instance, if you put pavers over a concrete patio, the height of the patio will be increased by the height of the brick. This may not be a big deal with certain applications, but in others it may be problematic. For instance, installing pavers over concrete for a pool deck may be a risky proposition, because if the pool pavers are too high, they may create a tripping hazard near the pool or may make people cut themselves when they are entering or exiting the area. Thus, you’ll probably want to install a new base for a pool area, unless you are using thin pavers and the heights work fine (see below about thin pavers).

Another potential problem when it comes to the heights of the new brick may relate to grades or slopes –  if you have issues with water pooling in particular areas, it probably won’t be corrected with this new paver installation. Make sure that there will be no problems with water as a result of this installation, as it will not be able to drain easily through the pavers with the concrete underneath – the last thing you want is a flooded yard or basement. You will also need to consider how you will surround the installation – with soil, mulch, or stone. Otherwise the concrete slab and borders will be exposed and will not look good. This amount of material could cause problems itself.

The Finished Product Depends on What’s Underneath

Third, installing paving stones over a concrete slab may be easier, and thus within the skill of a homeowner, the finished product may be somewhat disappointing. In particular, if freezing and thawing during the winter months cracks the concrete underneath, the patio, driveway, or walkway may be thus adversely affected, perhaps settling or developing its own unsightly cracks or sunken patches. Note that water and ice are constant dangers – if the water seeps through the patio and rests on the concrete layer below, and this water freezes, you may experience nasty heaving and settling.

Finally, the project itself may just not look as good as one installed over a proper base. For instance, efflorescence is a problem for all concrete paver installations. This is the phenomenon of a white, chalky residue appearing at the surface of the pavers. While this is entirely normal and will go away with time, the problem is exacerbated if the paver rests on a solid concrete bed.

If You Do Decide to Lay Pavers on Concrete…

Make sure that your concrete patio or driveway is entirely clean before you putting the pavers down. This will help prevent some future problems with your project. Actually installing the pavers will require some different methods and materials than a normal installation as depicted on other parts of the site. For example, you’ll probably have to use mortar for certain applications, as the standard sand bed/compacting method may not work. Make sure your contractor is trained in doing this procedure and has experience with it. If you are installing the project yourself, make sure you check with someone in the know (like an experienced contractor) who can help you with your particular situation and its installation.

Material Types Matter

In addition, using different materials on top will affect the conclusions described above. Using concrete pavers is one thing, but using stone or brick pavers over concrete is another. You will have less problem with efflorescence with these options, but you may have more drainage issues with them, and they may not withstand certain stresses well. Another thing to consider here is price and cost – if you are going to lay a lot of money out for expensive materials like natural stone pavers and flagstone, why not just go the extra mile and get it installed correctly on a fresh base?

One viable option if you’re just looking for a veneer on your project is to install thin pavers over concrete. These will replicate the look of regular pavers while also helping to preserve height – they are thin so that they don’t create a tripping hazard or mess up grades. However, note that they will have to be set with mortar, so you might have cracking and other disturbances appear, especially if the base below is faulty.

You could also lay down outdoor patio tile on top of an already existing concrete installation – this will give the project the new look that you desire with a fraction of the cost and time.

The Verdict

In short, installing pavers over concrete is doable, but has some negatives you need to be aware of. If money or time is not an issue, starting your project from scratch is the better choice. But if you are prepared to compromise on looks and customizability, installing paving stones over this base should work fine.