Maya Ellison
Ground-level decks are a great way to expand your outdoor living space. They can be customised to your liking and can be as simple or fancy as you want. When building a ground-level deck, you should consider factors such as ground contact, drainage, and materials. One common question that arises is whether plastic is necessary under a ground-level deck. Some people use plastic under their decks to prevent weeds from growing and to control moisture. However, plastic can negatively impact drainage due to its non-porous nature, leading to trapped water and accelerated wood rot. As an alternative, landscape fabric is recommended as it is porous, allowing for proper drainage and preventing weed growth.
| Characteristics | Values |
|---|---|
| Purpose | Prevent weeds from growing under the deck, prevent rotting, provide drainage |
| Pros | Weed control, prevent rotting, affordable |
| Cons | Traps water under the deck, accelerates rotting, not porous |
| Alternatives | Tar paper, gravel, landscape fabric, wire fence, concrete, aluminium sheeting, hardwood underlayment, clay fill, pea gravel, mulch, decorative stones |
Explore related products
What You'll Learn
- Plastic prevents weeds but traps water, accelerating wood rot
- Landscape fabric is porous, drains water, and prevents weeds
- Gravel is a cost-effective, simple, and durable alternative
- Tar paper over joists is a good way to prevent decay
- Plastic sheeting can be used to waterproof between decking and joists
Plastic prevents weeds but traps water, accelerating wood rot
Plastic is often used under ground-level decks to prevent weeds from growing through the decking. While plastic can be effective in weed control, it also traps water, accelerating wood rot. Water needs to be able to drain through the ground under a deck, and plastic is not porous, so the water becomes trapped. This additional water provides the moisture that fungi need to thrive, increasing the speed at which the wood will rot. To prevent this, the moisture content of the wood under the deck needs to be kept under 19%.
There are alternative materials that can be used under a deck that still prevent weeds from growing while allowing water to drain through. Landscape fabric, for example, is porous and allows water to drain through while preventing weeds from accessing sunlight, seeds, and nutrients from the soil. Gravel is another option that acts as a natural barrier against weeds while allowing water to drain through.
If you are set on using plastic under your deck, it is important to also use tar paper between the floor joists and the deck boards to prevent decay. Additionally, if your deck is less than 12 inches above the ground, you must have an open perimeter to allow airflow and prevent rotting.
Plastic's Deadly Impact: Killing Our Planet
You may want to see also
Explore related products
Landscape fabric is porous, drains water, and prevents weeds
Landscape fabric is a woven or non-woven material that acts as a physical barrier between the soil and the sun. It is designed to prevent weed growth by blocking sunlight from reaching soil-bound weed seeds. This, in turn, reduces the need for herbicidal weed control. Landscape fabric is porous and allows water and air to pass through it, although heavy rainfall may cause water to drain more slowly.
The fabric's ability to allow water to pass through it makes it useful for drainage applications. Non-woven geotextile fabric is commonly used in French drains, drain fields, and erosion control. It is also used to line the bottom of pots, planters, and raised garden beds to prevent soil from leaking out. Additionally, landscape fabric can be wrapped around drain tiles (perforated plastic piping installed in the ground to move excess water) to prevent the holes from becoming clogged with soil.
The choice between woven and non-woven landscape fabric depends on the specific needs of a project. Woven geotextile fabric is typically made from polypropylene or linen fibers and is known for its strength and durability. While it is commonly used in gravel or rock footpaths, highways, and parking lots, it offers minimal water drainage due to its impermeability.
On the other hand, non-woven geotextile fabric is known for its permeability and is commonly used for drainage applications. It allows water to penetrate without displacing the existing soil, making it effective in controlling soil erosion and separation. Medium-weight non-woven fabric is often used beneath gravel paths to separate the gravel from the dirt below, while heavyweight fabric is used in applications requiring strength and permeability, such as artificial lakes and retention barriers.
Creating Plastic Molds: A DIY Guide
You may want to see also
Explore related products
Gravel is a cost-effective, simple, and durable alternative
While some people opt to put plastic sheeting under their deck to prevent moisture from coming up through the ground, gravel is a cost-effective, simple, and durable alternative.
Gravel is a great option for creating a high level of drainage under your deck. As gravel doesn't absorb moisture, any water will run off instead of soaking into the material below, reducing the risk of dampness. Less moisture also means fewer mosquitoes and a lower chance of mould, mildew, or fungi growth. Gravel is also an excellent choice for weed prevention.
Gravel is easy to install and comes in a variety of sizes and colours, giving you plenty of options for your decking. It's also simple to make adjustments if you change your mind about the type of gravel you want or if you decide you'd prefer something else entirely, like mulch.
To install gravel under your deck, start by clearing away any existing vegetation or debris. Then, level out the ground as much as possible with a rake or shovel, using sand or soil to fill in any low spots and create an even surface. If there are large dips or bumps, consider using a concrete levelling compound for better results. You can then lay down landscape fabric, which helps prevent weeds from growing and allows water to drain properly. Finally, spread your gravel evenly over the surface.
Gravel is one of the more expensive options when compared to other materials like mulch, but it's still more affordable than concrete or pavers. If you're looking to create a patio area under your deck, gravel is a budget-friendly way to create an outdoor hangout space.
Plastic's Carbon Footprint: CO2 Emissions Impact
You may want to see also
Explore related products
Tar paper over joists is a good way to prevent decay
Water intrusion is the most damaging element to any deck structure. This is because the moisture can seep into the foundation, settle in cracks, and begin to eat away at the framework, causing rapid decay and compromising the stability of your deck.
Tar paper works in the same way as builder's paper or roofing paper, and it is one of the best things you can do to prevent the decay of the joists. It creates a very tight bond with the wood in a continuous line. When applying the strips, cut the adhesive to be at least a half-inch wider than the width of the joist. The edge of the tape will wrap around the corners of the joist, providing extra coverage over the edges and diverting the water's path.
Some people opt to use plastic sheeting to prevent moisture from reaching their deck. However, this may not be effective as the area under the deck is open to the outside air, and that air will dominate the moisture content of the air under the deck. A heavy-duty weed barrier under gravel can also be used to allow moisture to pass through and minimize weed growth.
Capping Off Plastic Water Pipes: A Step-by-Step Guide
You may want to see also
Explore related products
Plastic sheeting can be used to waterproof between decking and joists
One way to mitigate this issue is to ensure proper drainage and airflow. This can be achieved by cutting the plastic sheets in a way that creates a gradual slope to direct excess water away from the deck. Additionally, increasing the gaps or adding venting can improve airflow and reduce moisture buildup.
Another option is to use alternative materials such as aluminum flashing, coil stock, or joist caps. Aluminum flashing is a durable and effective way to waterproof between decking and joists. Coil stock, or aluminum siding, provides a strong and durable water barrier but requires special tools for cutting and bending. Joist caps are metal caps that fit around the top of the joist, providing a quick and easy way to protect against water.
It is important to note that waterproofing deck joists is crucial to the longevity of the deck. Proper treatment and protection of the framing will ensure that the deck remains standing for many years. While plastic sheeting can be used as a temporary measure, it is recommended to consult with professionals and explore alternative materials and methods for a more effective and long-lasting solution.
Meth Addiction: Plastic Spoon Chewing and Its Dangers
You may want to see also
Frequently asked questions
No, it is not recommended to use plastic under a ground-level deck. Plastic is not porous and will trap water under the deck, leading to fungi and wood rot.
Landscape fabric is a better alternative to plastic as it is porous and allows for drainage.
Landscape fabric prevents weeds from growing under the deck and kills existing weeds by blocking their access to sunlight, nutrients from the soil, and water.
Gravel is an ideal material for use under decks as it provides excellent drainage. It also helps prevent soil erosion and acts as a natural barrier against weeds.
Yes, gravel is a cost-effective material that is easy to install and comes in various sizes and colours. It also allows for more efficient irrigation practices as water drains through the small spaces between the stones quickly.
