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How Much Space Between Deck Boards?

Choosing the proper deck board spacing is a crucial part of the building process if you want to construct a deck that will withstand the elements. You may be wondering what the proper spacing is between deck boards. We've done in-depth research on this question and have answers for you.

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Providing space between deck boards is essential for the endurance and success of your decking. The proper spacing should be at least a 1/8 inch gap. Going beyond a quarter inch can be excessively wide.

Deck spacing is important. The results can be severe if your boards are not correctly spaced. This post will discuss why deck spacing is necessary, whether you should nail or screw deck boards, and what you can do if the boards on your deck are too close. 

Carpenter installing new wood decking - How Much Space Between Deck Boards

Space Between Deck Boards

slats of wood used for decking with spaces in between

On a deck, spacing refers to the narrow space from edge to edge. The amount of spacing between your deck boards may seem like a minor detail in a deck building, but it has a significant impact.

Without a gap, your project is vulnerable to a wide range of potential problems in the future.

Decks are continuously exposed to shifting humidity because they are outside and expand and contract in response to temperature changes. The wood will dry up and shrink in size throughout the winter when the humidity is noticeably reduced.

If the proper gapping is not used, your deck surface may warp or have large, ugly gaps between the boards.

Generally, a deck board gap should be between 1/8 inch and 1/4 inch. The International Building Code, which mandates a minimum 1/8-inch space between boards, is followed by many jurisdictions.

The eighth-inch spacing provides a safer walking surface and has less airflow, lessening the fire risk. Quarter-inch spacing also improves drainage, ventilation, and dirt removal. Additionally, it implies fewer boards, reducing the joists' load.

Wider gaps, however, increase the likelihood of tripping hazards. Your deck becomes more of a fire threat because of the increased airflow that wider gaps create.

Your deck will last longer if you leave spacing between your decking boards. The spaces between the deck boards also improve ventilation below the deck. This keeps the framework of your deck dry and rot-free.

Spacing is also critical for drainage. By leaving the proper spacing between your deck boards, you may prevent water from pooling on the deck surface and allow it to drain away. 

Why Is Deck Spacing Necessary?

New deck constructed from a Composite Decking Material. PVC Gray plastic with a wood grain. Supports and beams are real wood,cedar.

Deck board spacing describes the tiny spaces between your deck boards' long edges. Knowing how much room you'll leave between deck boards is crucial when planning your project. The distance between deck boards serves a few essential purposes.

Here's the purpose of deck spacing:

1. Expansion and Contraction

A spacing gap's ability to accommodate natural board expansion and contraction is its primary purpose. It is advisable to provide additional room so the wood can expand when wet. The expansion of wood increases with moisture content.

If you don't leave a gap, your boards can expand and bump into each other, causing damage, or they might shrink and leave gaps that are too big, making your deck dangerous to walk on.

2. Drainage

It's crucial to leave enough space between the boards for water to drain. If rain doesn't have a way to drain off the deck, the moisture becomes trapped, which can result in problems like rot and mold. 

3. Easy To Clean

Proper deck board spacing has the benefit of making it simpler to sweep away dirt from the deck's surface. It can also raise the deck's moisture levels and slow its drying process, leading to molds.

4. Security

When wet, some decking can become incredibly slick. This does imply not only a risk to your decking but also to you and your family. That's why it is essential to have spacing between decks.

Of course, the spaces between the decking boards must be the proper width. Both very little and excessively wide decking board spacing is problematic. For instance, a deck is more prone to fire if the gaps are greater. 

Is It Better To Nail Or Screw Deck Boards?

Strong hands preparing wooden boards in construction work outside in bright sunlight

Building a deck is better done with decking screws rather than nails. They have superior fastener/tensile strength and hold things flush better, which prevents boards from popping up over time.

Additionally, without causing any damage, you may remove screws for deck repairs and maintenance in the future.

Your deck will be exposed to different weather conditions, which will cause the wood to expand and contract. In these circumstances, screws will hold firmly, whereas nails will start to loosen and pull out. 

Click here to see these assorted wood screws on Amazon.

However, you must use nails unless you utilize more expensive structural screws. The typical stainless steel screws are pretty fragile.

Unlike nails, which will bend but are difficult to break in half, they will snap quickly. These nails contain threading intended to increase the nail's ability to bore into the wood and its durability.

Click here to see these hardware nails on Amazon.

Using a mix of nails and screws is also advisable when building a deck.

If you examine numerous project specifications and construction rules for decks, you'll discover that while some elements of the build require nails, others allow for the use of screws or nails.

What Can I do If The Boards On My Deck Are Too Close Together?

Wood planks texture background.

When deck boards are too close, air cannot circulate, and water cannot drain correctly. Your deck boards remaining wet might lead to wood rot, which can cause structural failure.

Cutting along the edges of the deck boards makes it simple to enlarge the space between them, allowing water to drain. To increase the distance between your deck boards, make clean cuts along the sides of the plank using a saw. 

Lower the saw blade and run it between the decking, softly touching one side to widen the space between the deck boards, and then check for clearance.

Watch the video below for more information on what to do if you deck boards don't have a gap.

Use a saw like the one below to cut the boards on your deck.

Click here to see this circular saw on Amazon.

Where Do You Start Laying Deck Boards?

Carpenter installing new wood decking.

The majority of decking was made of wood for a very long time. Although wood has many outstanding natural properties, it also needs some upkeep. 

Installation of decking is much more straightforward than you may imagine. Decking is currently available in a variety of shapes and sizes.

Your decking is incorrectly installed if it is laid ridge-side up. Most decking should be installed on the smooth side with the ridges to prevent rot and mold.

Should Deck Boards Be Perpendicular Or Parallel To My House?

An attached deck often runs parallel to the house by default. Since the joists must run vertically if the deck is connected, the decking planks will parallel the house. Construction of the deck framework, water runoff, and look are a few causes for this. 

However, a deck that runs perpendicular to the house is advantageous from a structural, aesthetic, and financial perspective. The decking boards may run perpendicularly in cases where the deck is not attached to the house.

In Closing

Installing a solid wood deck is a significant investment and will give your garden or home a stunning focal point. You must avoid leaving too little space between deck boards because this could obstruct proper drainage.

While installing the wood, you must be mindful of its moisture level to ensure that the spacing gap is not too wide after it dries out and contracts.

You should read, understand, and adhere to the written installation instructions provided by the maker of the composite decking.

We strongly advise speaking with a decking expert if you're still unsure how large a gap is for your particular wood decking.

They will be able to assess the wood's moisture content, advise you on the ideal spacing, and assist with installation to guarantee everything is done correctly.

We hope you found answers to your space decking problems from our article. Before you go, make sure to visit these other posts:

How Much Space Between Joists For Decking?