So, you’ve taken on the ambitious project of building a deck. You’ve completed the framing and have finally reached the fun part–laying the deck boards. You want the decking to have enough screws to be secure and safe, but you don’t want your beautiful deck to be riddled with screw heads either. So, how many screws should you put per deck board?
Each deck board should be fastened with two screws at each point where the board crosses a joist to ensure the stability and durability of your deck’s surface. Boards should be fastened to rim joists with three screws.
In this article, we will explore how to properly use screws to attach deck boards to a deck and the many options to consider when selecting deck screws.
- How Many Screws per Deck Board
- What Type of Screws to Use for Decking
- How Many Screws Do I Need for My Deck
- How to Screw Deck Boards
How Many Screws per Deck Board
Deck boards are exposed to all kinds of extreme weather conditions that make the boards prone to warping, cupping, and crowning. The deck’s screws are the only things standing in the way of the elements wreaking havoc on your deck, so you need to use the right amount.
You should use two screws at each point that the deck board crosses a joist to hold the boards firmly in place. Three screws should be used to secure the decking to rim joists.
What Type of Screws to Use for Decking
Many people use nails instead of screws to secure their deck boards. Nails will do the job, and with the use of a framing nailer, can make the job go much more quickly. However, there is a downside to using nails to secure decking. Over time nails tend to work their way back out of the wood. This will eventually cause deck boards to come loose, creating a need for constant maintenance.
Screws, on the other hand, are much more likely to hold boards in place because they are threaded. This makes screws the better choice for this project, but only if you choose the right ones. Walk down the hardware aisle of any home improvement store, and you’ll quickly find that there are dozens of types of screws for all manner of projects. What at first might seem like a simple task, can quickly seem quite complicated.
What kind of screws is appropriate for securing deck boards? How long should they be? What color? Are screws for pressure treated wood different than screws for composite materials? What if you don’t want your friends and family to see those unsightly screw heads when they come over for that barbecue next week? First, remember that you need screws that are for exterior use. So, for this project, you will need either galvanized screws or corrosion-resistant screws to prevent rusting.
The type of decking material you are using will also determine the type of screws you need to buy. It is important that you use galvanized, stainless steel, or wood deck screws for treated lumber. Today’s pressure-treated lumber is made using two copper-based wood preservatives. While these preservatives do a great job preventing your deck from rotting, they will also corrode ordinary metal screws, ultimately resulting in the structural failure of your deck. For decks constructed out of cedar, use a stainless steel deck screw. Hot dipped galvanized screws are also an option.
Composite decking should be fastened using composite deck screws. Wood screws will bore a hole into composite decking instead of biting into it. Composite deck screws are designed to fasten the composite boards to the framing tightly.
When deciding which screws to purchase, remember that they will be visible, so color matters. Standard wood deck screws are grey, but deck screws are made in a wide variety of colors. It’s important to consider what will look best for your color and style of the deck when choosing deck screws unless you plan to use a hidden fastening system.
All three deck materials give you the option of using a hidden fastening system. As the name implies, hidden fasteners such as the CAMO Edge Deck Fastening System hide the fasteners from view, creating a clean look for your deck. If you decide to use the CAMO system, you will need to purchase the specially designed star drive screws that CAMO makes for use with this system.
Deck Screw Head Types
When deciding what type of screw to purchase you’ll also notice that screw heads come in all sorts of shapes ranging from squares to stars to your standard Phillips-head screw. All three will work, but some may increase the pace of your work.
The square recess screw heads reduce the slippage and subsequent stripping of the screw head that can be common with Phillips-head screws, allowing you to work faster. Star drive screw heads, also known as Torx screws, create six points of contact with the compatible drill bit and are more recessed than Phillips-head screws, allowing for more torque, more stability and hence more driving power. The trade-off is that star head screws are a bit more expensive.
Once you’ve decided whether to spring for star-head deck screws, you need to consider screw length. How long should your deck screws be? Deck screws should be 3.5” in length for 2-inch thick lumber or 2-½ to 3” for 5/4-inch thick boards for the screws to drive deep enough into the joists to hold the board secure.
How Many Screws Do I Need for My Deck
Now that you’ve selected the type of deck screw you want to use, it’s time to calculate how many to buy. You don’t want to overspend by buying more than you need, but there’s nothing more frustrating than running out of fasteners as you near the end of your project.
The basic rule of thumb here is 350 screws for every 100 square feet of deck surface for standard 6” wide boards (5.5” actual width) and 16” spaced joists. If you aren’t using these standard sizes, use an online deck calculator to determine how many you’ll need.
How to Screw Deck Boards
Fastening the decking to the framing might seem pretty straightforward once you know how many screws to use for each board. However, there are a few things to consider before you get started to maintain the aesthetics of your deck.
First, make sure to position your screws 1” from each side of the board to prevent splintering.
Second, consider your screw spacing. Screw spacing should be uniform throughout the deck to maintain an aesthetically pleasing appearance. I suggest snapping a chalk line along your boards to assure even spacing.
There are also a few things to consider when driving the screws. Screws should be countersunk, so they are flush with (or slightly below) the surface of the board. Overdriving screws can cause the boards to split.
Additionally, pre-drill pilot holes for board ends to avoid splintering the wood. Drive screws at an angle where board ends meet at a joist to ensure they are tightly fastened to the framing.
Although screws are strong fasteners, occasionally you may have a screw break off as you are driving it into the wood. This frustrating experience can slow your project to a halt as you try to figure out how to remove what’s left of the screw.
If the head of the screw is still intact, try using a screwdriver to remove it by turning the screw counter-clockwise. If the head has been sheared off, grab the remainder of the screw with a pair of pliers and attempt to remove the screw by twisting it counter-clockwise.
If you’ve been unlucky enough to have no portion of the screw protruding from the board, you will need an extractor bit for your drill. Set the drill to counter-clockwise, place the tip of the bit on top of what remains of the screw, apply pressure to the drill bit, and pull the trigger to attempt to remove it.
If you’ve decided to go the hidden fastener route by using CAMO System fasteners, the process is quite different. CAMO uses a guide it calls the CAMO Marksman tool, which is used to guide the screws through the sides of each deck board into the framing of the deck. You will need to purchase the CAMO Marksman tool as well as the specially designed fasteners if you go this route.
The deck boards that create the surface of your deck are the most eye-catching part of the structure. They create the aesthetic value of your deck.
The fasteners you select to attach your deck boards contribute to your deck’s beauty while helping to maintain its structural integrity. Properly selected and installed screws can create a beautiful finished product that will last for many years.
Eugene has been a DIY enthusiast for most of his life and loves being creative while inspiring creativity in others. He is passionately interested in home improvement, renovation and woodworking.
Determining Deck Board Spacing
When using wood decking, you want a gap of at least 1/8 of an inch after your decking has dried out. If you're using decking that's already been dried out, you can leave a 1/8-inch gap when you install.
The typical number of screws per deck board is two for each joist crossing for optimum structural integrity and stability.How long should deck screws be for 5 4 decking? ›
Working with 5/4 board (i.e. 1.25-inch thick lumber), means you'll end up with a planed and finished thickness of about 1.063 inches. This means you'll want to secure these pieces with a 4-inch screw if going into 6-inch joists.Can I use 2 screws for deck boards? ›
You should use two screws at each point that the deck board crosses a joist to hold the boards firmly in place. Three screws should be used to secure the decking to rim joists.How many screws do I need for 5 4 deck boards? ›
Decking: Fasten 5/4 decking with 2 1/2-inch coated screws or 12d ringshank or spiral nails.What is the correct way to lay decking boards? ›
“The proper way to install a decking board is ridge side down.” The ridges are designed to allow for airflow, to stop moisture sitting in the ridge, and allow for a stronger structure. These lead to a less slippery deck as the moisture can drain better, and it can air dry.Should a deck be 16 on Center? ›
Deck joist spacing should never exceed 16″ on center (with the exception of MAX deck boards, which allow for maximum 24″ on center). For a more rigid feel, 12″ or less may be preferred. If adding additional framing, be sure to keep all boards level and in plane across the tops.Should you pre drill deck boards? ›
In the past, no matter what type of deck board you were installing, the answer to this question would indefinitely be yes. However, with advancements in fastener technology, pre-drilling in most composite and capstock deck boards is no longer necessary.Is it better to nail or screw down deck boards? ›
Decking screws are better than nails when building a deck. Decking screws hold down your decking more securely than nails and will stop your decking from warping. Also, you can easily remove screws for deck maintenance without causing damage.Should you fill screw holes in decking? ›
It is not necessary to fill deck screw holes as these holes do not significantly affect the structural integrity of your deck. However, for your deck to have a clean finish, the holes should be covered. The easiest way to patch the screw holes is by using a wood filler.
Tip #1 - Fastening Deck Boards
This means using two screws on each end, and using two screws towards the outside of the boards at every joist along the way. Doing this will help keep the boards firmly in place and won't give it the freedom to warp or cup.
The two most common sizes used for deck posts are 4×4 and 6×6. When using 4×4 posts, place them no more than 6 feet apart, and when using 6×6 posts, no more than 8 feet apart.Do you need to drill a pilot hole for deck screws? ›
Pilot holes are necessary to prevent damage to the material and allow the screw to better fit into the material. You could try to drill without pilot holes but depending on your screw size and wood type it will likely split or crack the lumber.Why do decking screws have 2 threads? ›
To enable a better connection, deck screws feature a section of thread underneath the head which is narrower. This helps for increased deck pull up when compared to wood screws, which feature a thread from the tip to the head of the screw unless there's a shank section.Can deck screws hold weight? ›
Deck screws are not designed to resist shear like bolts and bolted joints are. That being said, most screws can hold between 75-125 pounds with more quality deck screws being able to hold above 200 pounds per screw. You can also double up the screws to hold more weight.How much weight can 2 wood screws hold? ›
Most screws will hold anywhere from 80-100lbs of weight.How much overhang should a 5 4 deck board have? ›
Whether you're building a wood deck or composite deck, you'll need to know the width of the decking boards. As an example, 5/4 x 6 pressure treated decking measures 5 1/2 inches wide. Keep in mind, that you want to maintain an overhang around the deck, 1 1/2 inches on each end is common.Is 3/16 gap between deck boards okay? ›
The Sweet Spot – Most people agree that 3/16” is a good gap between boards. Going more than a ¼” may get a little too wide. The width of a nail head is just about right. Treated Lumber – Usually treated lumber will have some shrinkage so you can butt the boards almost right against each other during installation.What is the rule of thumb for screw length? ›
The most important factor in screw selection is length. The general rule of thumb is that the screw should enter at least half the thickness of the bottom material, e.g. 3/4″ into a 2 x 4. The other factor is the screw's diameter, or gauge. Screws come in gauges 2 through 16.What does the G mean on screws? ›
Self Tapping Screw Gauge (g) Size (mm) 4.
Screw spacing is measured center to center. Place a ruler or tape measure against the plate or electrical box holes to get a precise measurement. Get the distance from the center of one screw hole to the center of the opposite screw hole (down to 32nds of an inch if need be).Should I put my deck boards tight together? ›
Leaving a gap between boards is critical for a well-built deck that will have space to drain, dry, expand and contract without causing the wood any damage. But, you also want to be sure you leave the right size gap: Go too small, and there won't be enough space; go too big, and the gap can become a safety hazard.Should deck boards be bark side up or down? ›
Heartwood is often more resistant to decay than sapwood of the same species. Clearly you would install lumber bark-side down to expose the more resistant heartwood region to the elements.Do you stagger joints on decking? ›
Staggering the seams or butt joints where the boards meet is an important part of how to lay out the deck boards. Staggering the deck boards decreases the number of screws or nails going into one joist, which can weaken or rot the joist more quickly.Should a deck be perfectly level? ›
Most contractors suggest sloping the deck 1/4th- 1/8th of an inch for every foot of decking. With this slope, the difference isn't terribly noticeable to those standing on the surface but your chance of ponding is reduced greatly.Should I use 2x6 or 2x8 for deck? ›
Commonly used joist sizes are 2-by-6, 2-by-8 and 2-by-10. For example, when you space joists 16″ apart — which is standard for residential decks — a deck spanning 9 1/2′ would require 2-by-6 joists, a 13′ deck would need 2-by-8 joists and a 16′ deck calls for 2-by-10 joists.Is joist Tape Necessary? ›
In order to protect your deck's substructure from weathering and moisture, protective tape for your joists is a must.Should you seal the ends of deck boards? ›
Protection for wood decking starts at the first cut. Applying a high-quality end sealer to freshly cut ends of deck boards, protects against drying cracks, splits, water damage & decay.Do you leave a gap when putting down PT deck board? ›
Leave Gap: If the pressure treated wood has been kiln dried after treatment (KDAT), leave a 1/8” gap (the thickness of an 8-penny nail) between the boards when attaching, since the wood will expand slightly over time.What should you not do when building a deck? ›
- Being Inattentive to Local Deck Building Code.
- Building Inadequate Deck Post Footers.
- Attaching the Beam to the Sides of the Support Posts.
- Incorrectly Spacing the Joists.
- Installing the Wrong Deck Boards for Your Use.
- Attaching the Ledger Board Directly to the Siding.
Screws are superior for laying down the decking. They hold things flush better and have a better fastener/tensile strength, which keeps boards from popping up over time. However, unless you use more expensive structural screws you need to use nails for structural elements and joists.What size screw is best for decking? ›
Deck boards are typically secured with 2 ½-inch to 3-inch deck screws. However, hidden fastening systems, like lag screws, can be a good option for railings and posts.How do you hide screws on a wood deck? ›
Use Painted Head Deck Screws
You can “hide” screws by making them blend into the boards. The easiest way to do this is with painted head deck screws. These screws are stainless steel, but their heads – the part that is visible when screwed in come in a variety of shades and colors.
Pilot holes are necessary if you're drilling into hardwood, laminate, or need a precisely located fastener. They're also recommended if the wood is likely to crack, or if appearance is important. You can skip the pilot holes when doing a rough build with softwood where appearance isn't important.Are 4x4 posts OK for a deck? ›
In the past, many decks were built with 4x4 support posts (also called structural posts). But these can bow seriously, even if a deck is only 3 feet off the ground. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them.How tall should deck posts be? ›
Deck railing height should be a minimum of 36 inches, measuring from the top edge of the top rail down to the deck surface. This applies to the broad majority of the United States for all residential decks, though a few states have different requirements.Can deck joists be 24 inches on center? ›
But sometimes, they can be a bit unclear when it comes to a crucial component of your deck frame – joist spacing. Decking manufacturers may recommend anywhere between 12 and 16 inches for commercial decks and 12 to 24 inches for residential decks.What gap should I leave between decking boards? ›
When installing new air-dried decking the proper gap ranges from 1/8 inch (3.5 mm) - 1/4 inch (6.5mm) depending on the environment. If you are installing air-dried decking during a rainy or humid season you may want to place the boards with a 1/8 inch (3.5mm) gap.How many screws do I need for a 6 inch deck board? ›
Each board should recieve 2 screws per joist, spaced about an inch from each edge.Can you put deck boards tight together? ›
There is no reason to put a gap between the ends (also known as butt ends or butt joints) of wood deck boards. Wood, both softwood and hardwood, is dimensionally stable in length regardless of temperature, humidity or moisture content. Keep the butt ends as tight as possible when installing wood decking.
Leaving a gap between boards is critical for a well-built deck that will have space to drain, dry, expand and contract without causing the wood any damage. But, you also want to be sure you leave the right size gap: Go too small, and there won't be enough space; go too big, and the gap can become a safety hazard.Should I pre drill my deck boards? ›
Do I Need to Pre-Drill My Composite or Capstock Decking? In the past, no matter what type of deck board you were installing, the answer to this question would indefinitely be yes. However, with advancements in fastener technology, pre-drilling in most composite and capstock deck boards is no longer necessary.Should deck boards touch the ground? ›
The number-one reason ground-level decking projects fail is a lack of ventilation. We always recommend at least 18 inches of ground clearance to allow for good air flow, but ground-level decks, by definition, flout this rule. Therefore, we don't usually recommend building a deck at ground level.Is it better to nail or screw deck boards? ›
Decking screws are better than nails when building a deck. Decking screws hold down your decking more securely than nails and will stop your decking from warping. Also, you can easily remove screws for deck maintenance without causing damage.How long should deck boards dry before installing? ›
One to two weeks is usually sufficient, as long as your wood is stored properly during this period. DON'T: Never install your wood decking or siding immediately. If your outdoor wood acclimates too quickly, you may get excessive surface checking, cupping, twisting, warping or other problems.What happens if deck boards are too close together? ›
Are the boards on your patio deck too close together? If so, they may cause deck rot. When the deck boards are too close together, water won't drain properly and air does not circulate. Your deck boards stay wet causing rot and that can lead to structural failure/ wood rot.