Should You Put Gravel Under a Deck? Everything You Need to Know

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Gravel has a number of benefits; however, this material may also detract from the structural integrity of a deck if not applied in just the right amount and proper manner.

There’s no one-size-fits-all answer since every situation is unique, so it’s important to weigh careful considerations when making your decision about whether you should put gravel under a deck.

In this article, we will explore the advantages, disadvantages, and costs associated with using gravel beneath decks so that readers like you can make a more informed decision regarding whether using it or another type of medium makes sense for their particular project.


Should You Put Gravel Under A Deck?

The answer to this question depends upon the kind of deck construction you have, as well as where and how the ground sits beneath it. If your deck is built close to a large tree or bushes, for example, then adding gravel underneath can provide necessary drainage and support.

This can also be beneficial if you live in an area with heavy rainfall and flooding occurs occasionally. Having a layer of gravel between your deck and its foundations can help minimize water damage caused by standing water or surface runoff.

Generally speaking, using gravel under a raised outdoor living space like a porch is almost always recommended unless removing old dry-rotted wood beams.


When Should You Put Gravel Under A Deck?

If you’re planning on building a deck, then you will also need to consider how and when you should put gravel under it. Not doing so can lead to excess moisture, as well as premature decay of the substructure beneath the deck.

Here’s a guide for when it is best to put gravel under a deck:

Right Before You Build the Deck Frame

It is important that you add gravel before you begin constructing your deck frame. This is because heavy machinery may cause the soil underneath to become compacted or disrupted during the build process, which could further prevent water drainage from occurring correctly. To ensure proper drainage and avoid structural damage, spread a thick layer of crushed stone over the entire surface where you are going to build your frame before you start laying down your boards.

After You Finish Your Lumber Deck Installation

Once your lumber installation is complete, adding gravel between each wood beam or joist helps provide additional stability and support for the structure of the deck itself.

It also has another purpose: Creating air gaps between lumber pieces allows rainwater or runoff to quickly migrate away from the deck boards and avoid accumulation underneath them.

Additionally, make sure any excess concrete supports used as a base for your structure are covered properly with rubber membranes meant for such uses.

If You Have Erosion

If your deck is located in an area prone to erosion or near streams or lakes, you’ll want to put gravel underneath it for extra protection against moisture. By using multiple layers of gravel, you create additional water channels away from the construction base of your deck that transfer the runoff downslope. This helps protect nearby grass and vegetation from excess moisture due to runoff from your deck.

If You’re Using Wood Construction

Using wood for the construction of decks creates many potential problems if they are not properly maintained (such as moisture damage, rotting wood, and insect infestation).

Placing crushed stone around wood construction adds another layer of defense against moisture damage by ensuring there’s enough space between the bottom of the wooden frame and the soil below so that water doesn’t collect beneath it.

To Help With Drainage Issues

Most decks are built on sloped terrain or require some form of grading before installation which creates drainage issues if not corrected properly prior to construction.

When dealing with poor natural drainage conditions around your deck area, adding gravel underneath gives excess water a place to go rather than causing potential pooling beneath its framework which could eventually lead to rotting beams over time due to prolonged contact with moisture-rich soil.

If You Need Extra Support

Gravel provides more stability than other softer materials like sand or soil because it offers better resistance against shifting forces such as wind load or ice buildup during winter months.

Gravel can also be used with steel post anchors to add support structures for decks located in areas with heavier snow loads and wind gusts, providing extra stability for extended use throughout all seasons.


When Should You NOT Put Gravel Under A Deck?

Having a deck in your backyard is an excellent way to enjoy the outdoors and increase the value of your property.

But if you’re thinking about putting gravel under your deck, there are certain situations in which it’s not a good recommendation. Here’s a look at when you should avoid putting gravel under a deck:

When The Deck Will Be Over Grass

Grass can be an attractive, low-maintenance option for ground cover but it can also be difficult to maintain when you place something like a deck or patio over it. The weight of the deck can reduce air circulation and cause the grass underneath to die off, eventually leading to problems with weeds, pests, and increased moisture levels that could damage the wood over time.

When You’re Building on Hilly Ground

Adding gravel underneath a raised deck is not advisable if you live in an area that has a hilly ground or sloped terrain. This is because when higher ground always defers gravity so water will tend towards the lower levels rather than outwards due towards the downspouts instead of into them resulting in flooding beneath your deck structure instead: therefore defeats its purpose.

Gravel may help distribute and divert some of this water but chances are it won’t do enough to stop flooding caused by heavy rains.

When Your Deck Has Poor Support Structures

Adding gravel under your deck is also not wise when your basic foundations don’t have strong support structures such as footings or posts deep enough into the solid ground below frost line depths against board rising water tables—you need properly constructed foundation supports first before adding gravel under your deck.


What Are The Advantages Of Putting Gravel Under A Deck?

Putting gravel under your deck can be a great way to protect the area beneath it and help you enjoy your outdoor space even more. But why should you consider this option? Here’s what you should know about the advantages of putting gravel underneath your deck.

Improved Drainage

One of the best reasons to put gravel under your deck is improved drainage. The slope of your land usually directs water away from the perimeter of your house, but if you have an elevated deck, this may not be an option.

With gravel in place underneath, it can absorb excess water, draining it away from the frame’s pressure-treated wood and helping reduce rotting and decay.

Creates an Uninterrupted Space

Gravel also creates a smooth surface on which outdoor furniture or other items can sit without benches or potted plants sinking into the soil below. This makes for valuable uninterrupted space for light chairs or sofas, as well as pathways that don’t need regular maintenance.

Keeps Weed Growth at Bay

Weeds can quickly invade gardens, especially when there are plenty of areas around decks where they can find shelter and start to propagate themselves.

Adding grit underneath the boards keeps them out so that you don’t have to worry about spending time removing them later down the line – a job nobody likes!

Additionally, any windfall seeds won’t be able to take hold when there isn’t enough soil in which they can start growing.

Offers Protection From Natural Elements

The natural elements such as rain, hail, and snow are relentless over time, particularly if they are hitting against wooden boards all year long. Gravel shields pressure-treated wood from these weather conditions by providing an extra layer of protection between them which helps maintain its longevity even further after installation; without having to go through laborious repainting work every summer!

Finally, including pea gravel on top of sand creates a quarrying technique that further reinforces structure beneath decks and heavier loads too like hot tubs or seating for example.


How To Put Gravel Under A Deck? Step-By-Step Guide

Adding gravel beneath your deck can provide drainage and establish a barrier between your deck and the ground. Despite its seemingly intimidating process, putting gravel beneath your deck is simple to do and does not require any special tools or knowledge.

Here’s our step-by-step guide on how to install gravel underneath your deck:

Step 1: Measure The Deck And The Space Where The Gravel Will Go

Measure out the dimensions of your deck including both length and width. Take this information and ensure that the space where you plan to put the gravel is at least 6 inches larger in all directions than what you measured in order for the gravel area. This allows it to accommodate a 2-inch space around all sides of the tank. Mark these measurements on the grass or ground.

Step 2: Remove Existing Sod or Waste Products

Using a shovel or other garden tool, begin removing existing sod from within the tent outline you marked with string earlier. Remember that since you’ll be adding material height to this area, it will no longer be equal to the grass (unless you also plan on raising portions of nearby areas as well).

Thus, make sure you are exchanging enough soil for materials, so there won’t be any issues post-completion.

Step 3: Dig Out The Area For Gravel Installation

Digging out an area requires patience but once done correctly, can provide incredible benefits in properly protecting elements under a structure or landscaping feature such as a shed or pool area respectively.

Before beginning excavation work however make sure that any utilities in proximity (e.g., gas lines) have been located correctly by either yourself or relevant professionals if necessary (it may be illegal for individuals to perform excise near communications cables, etc.).

After providing markings for any areas near utilities, go ahead and dig out for about 4-6 inches below the predicted grade level – making allowances for both compacted material and gravel weight.

This also gives room for optional stone dust/sand bedding layer throughout the installation project duration to reduce potential settling issues associated with soil composition over time as well as bridging between gaps given portion sizes added around the tank perimeter (if applicable).

Step 4: Install Filter Fabric and Cover the Drain Pipe

Place filter fabric onto dirt after digging has been completed – making sure it covers the entire surface including pipe outlets and surrounding sections that were dug prior.

Next, cover the drain pipe so water will directly enter the tank later on without becoming trapped in the soil during rainy seasons.

Consolidate all edges together using heavy objects such as stones/bricks if necessary – ensuring fabric cannot move during future operations hereon forward.

To further protect entry points from entering debris while at the same time offering reduced water velocity when entering the tank beneath.

Additionally, adding landscape fabric hereon up towards the interior perimeter is a good idea if it’s available too!

Step 5: Install Gravel

To add levels of appropriate fillers/gravel across sections compose an even distribution system beforehand such as grid placement.

To do this, create small divisions within surface areas both above extra piping holes left outside perimeters after excavations conclude before materials come into contact with terminal connectors.

This helps reduce unnecessary sediment buildup which happens often when allowing big material chunks directly onto plug connections!

Now after establishing the application method.

Use a pitchfork until finished layering respective parts together until the desired look is achieved through visuals ascertaining structural integrity is still intact with no irregularities or noticeable layers present!

Next, sweep off remaining excess additions that just settled into crannies before covering entirely underneath barrier areas again creating both aesthetically pleasing textures and more importantly long-lasting protection against continuously changing outdoor conditions!


How Much Does It Cost To Put Gravel Under A Deck?

Decks are an incredibly useful addition to any home, but unfortunately, they are expensive. If you’re looking for an easier and cheaper way to improve the look of your deck and keep it safe from flooding, putting gravel under the deck is a great solution. But what does this DIY project cost? Here’s everything you need to know about the cost of putting gravel under your deck.

The Cost Of Gravel

The cost of gravel depends heavily on the quality of gravel needed and how much is required. You can expect to pay anywhere from $5-$40 per ton or up to $550 per cubic yard depending on the type and size of gravel used.

The most common types of gravel used include pea pebbles, river Jacks, and crushed stones, which range in price according to size and shape.

Cost Of Labor

If you’re comfortable incorporating some physical labor into a DIY project, then installing gravel under your deck will be relatively simple and cheap as far as labor costs go.

Depending on the difficulty involved with laying out the bed, along with the hauling costs associated with moving the necessary material (gravel), labor costs could range from $50-$200 for a medium-sized deck area.

Tools And Supplies Needed For The Job

In order for this DIY project to be successful–and safe–you’ll need certain tools and supplies in order for that space underneath your deck to be properly covered in gravel: shovels/rakes, soil tamper bar(for tamping down loose material), wheelbarrow (for transporting materials), edging material (for maintaining neat edges), water hose with nozzle (for smoothing out uneven terrain), etc.

You may also require additional items such as bags of cement or polyurethane foam sealant if additional support or moisture prevention is needed beneath the ground level before adding proper drainage materials such as landscape fabric & stone or leveling sand.

Finally, each homeowner should budget around 10% more than estimated for potential unexpected costs like additional fill dirt or emergency repairs when making their overall budget for this DIY job.


What Type Of Gravel Should You Put Under A Deck?

Adding gravel to the area under your deck can give it a finished look, provide drainage and prevent weeds. But choosing the right type of gravel is important when selecting materials for the space beneath your deck. Let’s dive into what type of gravel should you put under a deck.

Cobble Stone Rocks

Adding cobblestone rocks is an excellent solution for underneath decks. They come in larger sizes than small pea-sized stones, offering more coverage over a greater area below the deck.

Plus, they don’t require much upkeep since they don’t need to be raked or stirred up like smaller gravelly types of material can be after heavy rains or windstorms.


Wood chips or mulch are also good choices when it comes to creating a soft layer below your deck that will absorb extra moisture from rain showers or during severe storm events where flooding could occur due to underground drainage problems.

Because mulches are organic materials, you won’t have any worries about rust stains that can occur with certain types of minerals such as iron ore dust which is sometimes found in certain kinds of rock deposits used for ground coverings beneath walkways and decks alike.

River Rocks for Decorative Appeal

If you’re looking for a more natural aesthetic with fewer shifts, then large river rocks might be right up your alley. River rocks come in a variety of sizes, shapes, and colors – which makes them perfect for enhancing any outdoor area nearby your deck with their attractive appearance.

The downside is that they can be expensive due to a higher cost per square foot than crushed rocks: ranging from $2-$7+.

Pea Gravel For Natural Filtration

If you need gravel that can act as a natural filter for any runoff that accumulates under your deck, then pea gravel may be the way to go. This type of landscaping stone comes in small rounded stones which provide excellent filtration by trapping dirt particles like a sieve yet don’t prevent rainwater from passing through as easily as river rocks do.

However, pea gravel is also slightly less visually appealing due to its smooth surface texture so it should only be used if filtration is necessary or desired over other factors.


Can You Build A Deck Over Gravel?

Building a deck over gravel offers several advantages to homeowners looking for a quick and cost-effective way of installing a deck.

The gravel bed can be used as a stable base for the deck instead of pouring concrete which can require more on-site construction and labor, thus speeding up the overall installation process.

Additionally, by utilizing this base underneath the deck, you don’t have to worry about drainage issues that may occur when using dirt or grassy surfaces.

Moreover, when installing any type of structure like a deck, it’s important to select professional contractors who are experienced in their field – since they’ll know how best to build something that won’t succumb easily to environmental factors like weathering or wet soil conditions.

Getting help from professional experts on these types of projects helps ensure that you get what you desire with minimal effort and expense in terms of both time and money invested over the long run!


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