Want a smart idea? Use gravel as a base whenever you’re trying to build a patio, driveway, or walkway. That’s a smart idea… but only if the gravel’s installed the right way. A lot of people tend to rush the whole process or they miss essential steps, which then leads to drainage problems and surface shift.
In this article we’ll go over five of the most common mistakes people make when installing gravel bases and as a bonus we’ll provide you with solutions and prevention tips for achieving a durable foundation.
1. Forgetting/Skipping Excavation
This is likely the most common mistake when installing a gravel base, and hence – first place. Skipping (or forgetting) the excavation step can end up costing you a lot of money; right from the start.
Laying gravel over dirt, grass, or existing soil might sound great, especially for small DIY-style patios or walkways. But if you go for that, you’re creating a fragile base. The depth depends on what you were thinking of doing (the project), the budget, and what kind of soil you have, things like that.
If you don’t dig correctly, organic materials such as grass or roots, they’ll all break down causing the gravel to sink or shift, or get uneven spots. Even if we’re talking about a spot that won’t be used much, skipping this step can (and probably will) lead to drainage issues which will cause surface wear way faster than expected; and this won’t look good then. Plus, it’ll likely spread. So, make sure not to forget this step. It’s very important.
How to fix it: For a stable base, you need to dig at least four to six inches deep (ideally even more). You’ll want to clear out any plants/roots. After all that has been done, you’ll need to pack down the exposed ground using a hand tamper or a plate compactor. If your project is building a driveway or expecting heavy loads, you can dig even deeper (up to eight to twelve inches). Twelve is better – it’ll cost you more but it's way better quality.
This ‘extra’ work at the beginning ensures your foundation won’t move or sink.
2. Using the Wrong Type of Gravel
If you’ve avoided the first mistake and dug out a proper base, that's a good start. Now comes the gravel. For the average Joe, gravel is gravel. That’s it. But if you’re a bit more into landscaping, or you’re a gravel expert then you know that that isn’t the case.
Not all the gravel is the same, and picking the wrong one can ruin the entire project.
Types of gravel:
|
Gravel Type |
Avg. Cost (per ton; in USD) |
Ideal Base? |
|
Crushed Stone (aka Angular Rock) |
30-45 |
Yes |
|
Pea Gravel |
30-60 |
No |
|
River Rock |
80-280 |
No |
|
Decomposed Granite (aka DG) |
25-50 |
Yes |
|
Crushed Granite |
25-50 |
Yes |
|
Marble Chips |
85-400 |
No |
|
Lava Rock |
120-200 |
No |
|
Quarry Process (aka QP, or Crusher Run) |
25-35 |
Yes |
|
Jersey Shore Gravel |
85-100 |
No |
For example, a lot of people go for gravel that looks good, something like pea gravel. It’s nice, and it doesn’t cost too much, but the thing is that pea gravel doesn't pack down well, and it moves around way too much.
Also some super expensive options such as lava rock or marble chips may seem like ‘premium options’ but these will suck your wallet dry, plus they make for a horrible foundation.
How to fix it: Crushed stones (most often limestone or granite, depending on region) or crushed runs are excellent options for a solid base. And both options are cheap. Their sharp edges help them lock in together, which helps in forming a firm/sturdy foundation.
If you like one of the ‘not ideal bases’ in terms of looks, you can spread a thin layer on top of the crushed stones. This way, you’ll get a firm foundation and even an attractive finish on top.
What I would do is I’d call in my local supplier and check the gravel options and the pricing. Perhaps one of the options is on sale, which will help you in terms of budget. I’d also find gravel delivery near me since transportation could be a hassle if you don’t have a truck or a trailer. Once it’s delivered to my door, it’s ready to go.
3. No Layer Compaction
If you want to avoid a bumpy and weak patio or driveway, don’t forget to smash down the gravel. This has already been mentioned in the first mistake, but it’s so important that it gets its own entry. Many people just dump gravel on the top of gravel and high-five themselves thinking they’ve done it. But since you’re already paying for it all and you’re doing the work, you might as well do it properly. If you dump the gravel without compacting it, you’ll be left with a loose grave that’s prone to shifting – and that’s not good.
How to fix it: Spread about two to three inches of gravel, and pack it down tight before you add another layer. Continue until the base reaches the right height. If you have a hand tamper, you can use one, or use a plate compactor (a machine used to flatten the gravel). Make sure you don’t rush and do a few runs to be sure it’s all nice, flat, and even.
Packing each layer tightly makes the base solid, which stops it from moving/sinking later on. This way, you can save a lot of time and money, plus whatever’s on top will last you a very long time.
4. Ignoring Drainage
The fourth most common mistake people make has to do with drainage. If the water can’t flow from the gravel base, it’ll simply sit there without being able to escape, leading to mud, puddles, and sinking spots. If you don’t have the right slope or you’ve skipped step one, then you’ll quickly be left with water build-ups, which’ll end up haunting you.
How to fix it: Always make sure the ground isn’t fully flat but there’s an angle. It needs to be angled at least 1-2% so that water can run off (1% is enough, but 2% is better). An additional good-quality step is placing some landscape fabric underneath the gravel. It’ll cost you a bit more, but you’ll get better and longer-lasting results. For extra points, you can additionally install a small drainage pipe under the base to assist with water flow out.
It’s very important you do this as well because if the water just sits there, it’ll soak the soil and ruin the base. It won’t happen overnight, sure. But you’ll run your car over, or you might even walk over it and it’ll start cracking and sinking. After that, it’ll only get worse.
5. Miscalculating The Amount
Ensure you order the right amount of gravel. Some people run out halfway through the project because they didn’t order enough, which is fine. It happens, especially if it’s your first time doing it. That issue can happen when you’re just guessing it or eyeballing it. But instead of ordering more, some just say “whatever, that’s good enough!”. But... it isn’t good enough.
When you don’t have enough gravel, it’ll result in a thin base that won't hold up. It’s almost as if you don’t have a foundation at all.
How to fix it: Measure the space's length, width, and depth where you’re working. There are online gravel calculators that can help you with that and you figure out how much you need. To be ‘extra’ sure, always order about 5-10% more. This way you’ll definitely have enough. And the surplus you can later use for other projects.
Conclusion
The whole point of this article is that whatever project you’re doing requires a solid base and we’re here to show you how to create that foundation properly. Dig, make a slope, choose the right type of gravel, compact it well, make sure there’s enough, handle drainage. It’s that simple.
This way, your patio will be solid and it’ll last you for the foreseeable future.
