As summer approaches and outdoor home renovation projects are on the rise, a common question often asked by DIY enthusiasts regarding deck building is ‘should I pre-drill holes for decking?’ Well, I have the answer for you below as well as the answers to other questions related to working with wood. Let us get right to it, shall we?
The main purpose of pre-drilling holes for deck screws is to prevent the wood from splintering. When it comes to driving screws close to the end of the deck boards, pre-drilling holes is often the only way to do this without ruining the wood. Pilot holes also prevent your screws from stripping or breaking off. It is much easier to drive screws into hardwoods (like ash, oak, or maple) when holes are pre-drilled.
Now that you know it is recommended to pre-drill holes for deck screws whenever possible, let us explore this further and in more detail. I will explain the correct way to pre-drill wood screws as well as whether (or not) you should countersink deck screws. I will also discuss how long screws for decking should be, how deep the screws should go, and which screw types are the best.
So, if you are reading to learn more about pre-drilling deck screws, then please continue reading…
Do You Need to Pre-Drill Wood Screws?
While it is not considered necessary to pre-drill wood screws, it is highly recommended by professionals that you do so.
When you do not drill pilot holes in advance, you are essentially putting extra pressure on the wood surrounding the screw (weakening it) and increasing the chances of the wood splitting or cracking.
It is a precautionary measure worth taking and will always pay off in the long run!
When working with solid wood, the most effective and long-lasting fastening power will always come from pre-drilled holes such as pilot and clearance holes.
A clearance hole is a hole drilled through the top of a board to prevent jacking. It must be big enough for the body of the screw to fit through without the threads immersing in the wood.
What is the Proper Way to Pre-Drill Wood Screws?
To drill pilot holes correctly, follow the necessary steps listed below:
- Begin by examining your power drill to ensure it is in good working condition.
- Load the right size drill bit into your power drill.
- Mark the spot where you intend to drill the hole.
- Set the power drill to level 2.
- Drill the pilot hole at a 90-degree angle through the deck board into the frame or joist.
- Load your drill bit into your power drill. For accurate drilling use a brad point bit.
- Set the power drill speed setting to level 1.
- Drive the screw straight down into the board, making sure the head is flush with the surface of the board.
A few things to keep in mind: the pilot hole should be at least as big as the screw’s minor diameter.
If the screw has deep threads or the wood is hard, drill the hole slightly larger than the screw’s minor diameter, but not too large. For softer wood, drill the pilot hole slightly smaller than the screw’s minor diameter.
Also, be sure to enlarge the pilot hole enough to make a larger, clearance hole. This larger hole allows the screw to pull the 2 boards together. The clearance hole should be at least as large as the screw’s major diameter.
Omitting the clearance hole step will likely leave a gap between the 2 boards. And, unfortunately, the glue will not bridge the gap effectively.
In general, glue only works to close gaps that are no wider than the thickness of a piece of paper.
What is the Right Way to Install Deck Screws?
The best way to install deck screws includes the following 6 steps:
- Visit your local hardware store or go online and purchase a good deck screw kit with stainless-steel screws and a minimum length of 2-1/2” – see below under the subheading entitled: What are the Best Deck Screws?
- Begin by laying the deck board directly on top of the frame. Mark the top of the board with a pencil to indicate where each baseboard is located underneath the deck board.
- Place your deck screws at least 1 inch from the edge of the board. If the screws are installed too close to the edge, you run the risk of splitting the boards.
- Set your drill at the lowest speed to allow for complete control over the tool. Put your weight behind the drill and drive the deck screw straight (not at an angle) down into the board.
- Ensure the deck screws are flush with the top of the board, if possible – slightly deeper than flush is okay too.
- Make sure the deck screws are installed at approximately the same distance apart on each board. This will create symmetry. The idea is to install the deck screws in such a way that they are unnoticeable, blending seamlessly into the overall appearance of the deck.
How Long Should Screws be for Decking?
Most deck screws, on average, are 8-gauge with a minimum length of 2 ½” needed to securely attach decking boards to the joists.
Most professionals opt for slightly longer screws (around 3”) for extra holding power and the guard against the upward pressure of shrinking and/or warping boards.
Should I Use Nails or Screws for Decking?
For decking, you should always use screws rather than nails. Nails are dangerous and can pop up and out of the wood.
They also corrode more easily. And, while screws are generally more expensive, they hold more securely and tend not to rust.
How Deep Should Deck Screws Go?
Deck screws should be placed at least 1” away from the edge of the board. If you install the screws too close the edge, you increase your chances of splitting the wood.
The general ‘rule of thumb’ is that the screw should reach at least halfway through the board.
Should You Countersink Deck Screws?
Typically, when you drive a screw into wood, you stop as soon as the screw head hits the surface.
Countersinking basically means you are going to continue to drive that same screw below the surface. If you choose to face-drive deck screws, then it is okay to countersink them.
How Many Screws Do I Need for a 6-Inch Deck Board?
On average, you need about 350 screws for every 100sqft of the deck surface. This is based on 6” wide boards and 16” spaced joists.
To hold the board securely in place, use 2 screws at each point where the deck board crosses a joist and 3 screws to fasten the decking to the rim joists.
What are the Best Deck Screws?
The best deck screws are corrosion-resistant and able to withstand the elements. Look for stainless steel or galvanized (or zinc coated) decking screws, if possible.
Amazon has a great option available for purchase online – Eagle Claw Stainless Steel Deck Screws. (affiliate link)
These screws come with 350 type 304 grade 2-1/2” stainless steel screws which are perfect for decking, fencing, walkways, jetties, and general-purpose woodwork. They are rust-resistant and suitable for hardwood, softwood (like redwood and cedar), and even pressure-treated wood.
Do yourself a favor and check it out today!
To sum things up, the main reason for drilling pilot holes in deck boards is to prevent the wood from cracking or splitting.
Pre-drilling holes is often the only way to successfully drive screws into the ends of deck boards without wrecking the wood.
Pilot holes also stop crews from stripping or breaking off, which is a major hassle. As well, it is easier to drive screws into hardwoods when holes are pre-drilled.
I hope this article has been of help to you. Thanks for reading and good luck with your future decking project.
Cheers, tools owners!