Should A Patio Be Level With The Grass?

The first ground level apartment I ever lived in had a small but sweet 10’x10′ patio that was wonderful for grilling out on and entertaining family and friends since a small joined plot of grass came with it. The only problem was that tons of dirt and grass kept on creeping onto it. I later came to find out that my patio was too low compared to the grass.

Should a patio be level with the grass? Your patio should be at least level, but generally between .5″ and 1.5″ above grade. This provides adequate distance so that creeping grasses will not crawl onto your patio and dirt will not wash onto your patio during heavy rains or foot traffic.

Realizing what my problem was all along, I decided that at my first house I would be sure to make my patio the proper distance from the ground as well as include a couple other features that may not be so common sense.

How High Your Patio Should Be

Your should shoot for your patio to be .5 to 1.5″ above grade. Well, what does that mean? Your yard generally has some sort of slope to it, even if it is no slop. A 1% slope is when your yard goes down 1″ for every 100″ of travel. To be pleasing to the eye you don’t want the grade of your lawn to be very different than the patio. We will discuss these details in a little more depth below.

Patio Height

Lets get more into the patio height. As stated, .5 – 1.5″ above grade is ideal. In some cases that may not be possible, or if you are going for a specific look like a step up patio or you want to put steps up to your patio you may build it slightly higher. What you need to balance is visual appeal and structural integrity.

Yup, structural integrity can be diminished if you do not have a sufficient amount of material on the side of your patio. This can lead to cracking of the stones, misalignment of the stones, stone rotation, breaking apart of the polymeric sand used to hold it together and more. If you still want your patio to be tall than you can have it, but you need to make it sturdy in other ways such as a retaining wall, adding a concrete layer on the outside, or making it less than 1″ above the ground.

Patio Slope

As already said, you want your patio slope to be similar to your yard slope with a goal slope between 2-3% to be more pleasing to the eye. Normally your yard is highest at your house and slopes downward as it moves away so that water will drain away from your home and its foundation. This is perfect as you also want your patio to do the same thing so you don’t have pooling on top of your patio which can cause both degradation of the polymeric sand used to bind it as well as cause unwanted blemishes from the water and the impurities is carries.

If your yard is perfectly level, then congratulations cause it probably looks beautiful, but you probably also have some problems with pooling water unless you have an installed drainage system. In this instance having a 1-2% slope difference in slope from your patio to the yard is fine as it will not change the appearance too severely. If you are an unlucky individual whose yard slopes toward the house then you may want to get that taken care of before you go any further as it may cause more problems down the road.

Steep Slopes

Lastly it may be that you have a very steep slope in your backyard. In this instance, you may just need to find the spot that you want it in and level that part while also adding something to keep the dirt and patio from sliding like a retaining wall of some sort.

Basics On Your Patio Foundation

How does this relate to building a patio? it really only affects the process of planning the depth you will dig and the amount of materials you need to fill the hole you just dug. Yes I know, I don’t like digging holes just to fill them, but there are some pretty good reasons we do those steps. Below we will talk about how critical your patio foundation is to making it level with your grass.

Depth

How deep to dig beneath your soon to be patio depends on its use. The more weight it is going to bear, the deeper you need to dig because the more base material you will need to compact beneath it to increase the strength of the patio. For example, the average backyard patio only requires 4 – 5″ of paver base material, but a driveway would need upwards of 8″ of paver base. This means, unless you plan on parking your car on the back patio you are probably ok with just 4″.

Thats not all yet, you need to add in 1″ of sand which provides a compressible base to level the patio pavers on. Lastly you need to add in the height of your pavers, which on average will be between 3 – 3.5″. So to calculate the total depth beneath your patio with a 3″ paver, it would look like this.

4″ paver base + 1″ sand + 3″ paver = 8″ deep

Filler

Now that you have your hole, what to fill it with? Pretty much every professional that installs patios will use crushed stone as a paver base. This means that stone dust, sand, and compacted soil although may seem like ok alternatives, will not even last a season. Structural integrity will decay rapidly and you will have a sliding and moving patio on your hands.

For the absolute best results, crushed stone should be laid 2″ at a time and tamping it in between. For the most consistent strength throughout you want to do it 2″ at a time and consider even wetting it in between as well as this will help it to settle into its final shape. You do not want your base to shift on you once a big rain comes.

Once your crushed stone is completely laid, lay your 1″ of sand, and you want it to be 1″ on the same grade that you want your patio. One of the easiest ways to measure this is by using 3/4″ PVC pipe laid on the gravel as it is 1″ in outside diameter. Use two pipes and once you poor the sand on the ground, use a long level to smooth it out. This is common practice for contractors.

Pavers

Next is laying your pavers, and you want to make you do not slide them to put them in place. If this step is done wrong you will have an uneven patio. Hold your paver above the ground and press it up against the side of the neighboring paver without it touching the sand. Then allow it to slide down the side of the neighboring paver snuggly fit against every paver on all sides.

Why You Build It This Way

The reason these steps are the most critical has to do with the structural integrity of the base. The polymeric sand in between the pavers will slowly erode away due to weather and washing, but if you have a strong base than you will never have to worry about your patio or its pavers shifting unless all of the earth around your house is shifting as well.