Selecting the best fastener for your project can be frustrating. What will work best? Deck screws vs wood screws, it’s sort of like comparing one kind of apple to another kind of apple. Both are threaded, have a point, a shank, and head, are made of metal, and can be driven by hand or mechanically, but they aren’t the same. They are designed for different uses and purposes.
Wood screws is an all-encompassing name that includes standard wood screws and deck screws, plus other types of screws. Deck screws typically have deeper threading, a self-drilling tip, are made of stronger metal, and coated against corrosive elements and compounds. Standard wood screws have shallower threading, require predrilling, and a more cone-shaped throat to pull and clamp wood pieces together.
In this article, we’ll explain what deck screws and wood screws are, look at their differences, and uses. We’ll also compare wood screws with metal screws and construction screws, and look at some of the best deck and wood screws. Our goal is to provide you with the information to select the best fastener for your projects.
- What Are Deck Screws?
- What Are Wood Screws?
- Deck Screws vs Wood Screws: Key Points
- What is the Difference Between Deck Screws and Wood Screws?
- Are Deck Screws Structural?
- Wood Screws vs Metal Screws
- Wood Screws vs Construction Screws
- Best Deck Screws
- Best Wood Screws
What Are Deck Screws?
Deck screws are a specialized form of wood screw specifically designed for outdoor use and to hold soft or hardwood decking in place as they flex while people walk on them. They typically are steel screws coated with a corrosion-resistant material for protection from various weather conditions or wood treatments, or they are stainless steel that doesn’t corrode. The screw is durable, has a higher load-bearing capacity, and will grip deck boards tightly to the under framing.
Deck screws have a larger head surface to prevent them from sinking into the wood and splitting it, and to hold the board firmly. The threading is deep, sharp, and tapered toward the tip for cutting into the plank and holding it, and the upper third of the shank is often smooth. Some deck screws have reverse threading on the upper shank to prevent the decking from mushrooming, and some have a split thread at the tip for faster driving and an initial bite into the wood.
Types of Deck Screws
There are dozens if not hundreds of different deck screws on the market of various lengths, gauges or diameters, thread count, head size, and drive mode. Most, however, fall into one of six categories:
- Regular deck screws are zinc or ceramic coated steel for protection from corrosion and chemical treatments. They are available in different lengths and diameters or gauges, drive configurations, and grip the wood to hold well.
- Structural deck screws are more for load-bearing since they’re thicker and have a greater shear rating. They are typically used for fastening railings, posts, joist to beam, and ledger boards.
- Stainless steel deck screws are similar in shape and structure to regular deck screws but are much more resistant to corrosion. They are commonly code required when building near or on saltwater and are more expensive than regular deck screws, so aren’t often used unless required. Stainless screws are also recommended for use with cedar planks as they won’t discolor the wood.
- Hidden deck screws are often brand-specific and designed to drive on an angle into the side of a deck board using a specialized guide, thus leaving the top smooth and unmarred by screws or splinters. Another type drives into the top of the board and the head self-bores below the plank’s surface, and a matching plug is then glued and tapped into place to hide the fastener.
- Composite deck board screws are also brand-specific and commonly have a smaller head, higher thread count, and reverse threading under the head to prevent mushrooming around the head. Screws are coated to prevent corrosion and to match the plank color. Most composite screw heads require a Torx or star driver too.
- Lag bolts are a cross between a bolt and a screw. They are commonly heavy 1/4″ or heavier gauge, have a greater shear rating, and usually have a hexagonal drive head. While they are driven in like a bolt, they have a tapered threaded shaft with a point for biting into the wood. They are typically used for fastening lumber together, and the head may be countersunk or not, and used with or without a washer. Available in a variety of lengths and diameters, they are typically zinc-coated steel to resist corrosion, but also available in stainless steel for greater resistance to corrosion. Another type of lag bolt has a flat, washer-like head and is driven by a hex head or Torx driver.
What Are Wood Screws?
There are literally thousands of different screws on the market, but not all of them are wood screws. Wood screws are used to fasten two or more pieces of wood together for cabinetry, furniture, interior or exterior framing, or mounting hardware. Wood screws come in a variety of metals and colors, lengths, diameters or gauges, tips or points, threading, shank lengths, head shapes, and drive receivers.
Historically, wood screws had slotted drive heads which were easy to strip if over-tightening. Today, slotted drive heads are still in use, but different drives have been developed. The Phillips or cross-head drive is common in the USA, the Robertson or square drive is common in Canada, while the six- or eight-point star in parts of Europe.
The different drive receivers allow for more surface contact with the driver, and thus more torque. The drawback to more torque though is the risk of breaking the screw head off at the shank or splitting the wood.
A wood screw typically has a smooth shank between the threading and the head while a screw for holding metal, plastics, or other materials is commonly threaded from tip to head. Wood screws have a sharp point to enter the wood but may require a pilot hole to prevent splitting or cracking the wood.
The threads on the screw bite into the wood around the pilot hole and don’t have to displace any wood material. The smooth shank spins freely in the outer piece of wood and doesn’t impede the screw, while the fine, sharp threads pull the inner piece of wood tight to the outer piece.
Wood screws usually have shallow non-tapered threading. Those used to fasten hardwood commonly have more threads per inch or tighter threading than wood screws used to fasten softwood. Wood screws are available with a variety of heads for different uses. There are flat, pan, oval, washer, and countersink wood screw heads, with different designs within each drive head shape.
Types of Wood Screws
Wood screws come in numerous lengths, diameters, threads per inch, thread depth and angle or pitch, head shapes, and drive options. Their use often determines what wood screw is best for the task. Typically, there are six categories of wood screws, with each category having a plethora of subcategories.
- Standard wood screws are the most common category and are available in numerous diameters and lengths. These screws are used to fasten wood to wood or hardware to wood. They are non-structural in that they are used for joining and holding, not for shear force or stress use. While most are made of untreated steel, brass, or copper, some steel screws are colored to look like copper.
- Deck screws are designed for outdoor use to hold deck or fence boards in place or to build outdoor furniture, planters, or other outside projects. They are treated or coated to protect from corrosion, or made of stainless steel. They typically have deeper threads and larger heads for greater load-bearing and take a multi-sided drive tool like a Philips, Robertson, or Torx head, not a slot or flat driver for greater drive torque.
- Pocket hole screws are most often square drive or Robertson and used to build cabinetry or furniture. They have a flat-bottomed pan or round washer head and need to be pre-drilled to set the head into the top piece of wood. The flat bottom or washer helps pull the two pieces of wood tight and prevents the head from countersinking or pulling through. The screws are self-tapping so a pilot hole into the second piece of wood isn’t necessary when joining two pieces of wood together. A pocket-hole jig is often used today to pre-drill and angle pocket holes.
- Drywall screws are typically phosphate coated and have a cross or X (Phillips) drive and are used to fasten drywall panels to wood framing. The black finished steel screws have a sharp coarse thread from the sharp self-tapping point to the head, with some having a higher thread count than others. The underside of the head is designed to countersink the flat head for finishing. Available in various lengths based on the drywall thickness with 1/2″ panels requiring 1-1/4” screws and 5/8” sheets fastened with 1-5/8” screws.
- Structural screws are a cross between a lag screw and a deck screw. They look more like a deck screw but are larger and designed to bear greater loads and shear forces, like a lag screw. They are used to fasten structural load-bearing members, such as ledger to wall or post to beam together. They are either stainless steel or treated against corrosion.
- Lag screws or bolts are designed for joining heavy load-bearing structural members. They are a heavier gauge and have thicker threads than screws, and a high-torque hex head for driving with a wrench. Available in different lengths and gauges, they are often used with a heavy washer to prevent the head from sinking into the wood, and for greater support.
Deck Screws vs Wood Screws: Key Points
Comparing deck screws to wood screws is a matter of looking at coating, shank, threads, and head size to determine which is which or reading the box. Deck screws are a specific type of wood screw designed for outdoor use. Standard wood screws are designed to join two pieces of wood together for cabinetry or furniture, and typically have a narrower shank and shallower threads. Here’s a table to help compare the two screw types.
|Deck Screws||Wood Screws|
|Material||Coated steel or stainless steel||Steel, brass, copper, or stainless steel|
|Corrosion Resistance||Yes, providing coating isn’t chipped or scratched||Not normally unless stainless steel|
|Head Shape||Flat head with greater surface area with a flared or bulged throat to prevent sinking into wood. Hex-headed for heavier screws.||Flat countersinking, pan, oval, or washer-head.|
|Drive Type||Phillips or X, star or Torx, and Robertson or square drive or hex-headed for wrench use.||Commonly slotted, square, or cross drive, and may also be a star.|
|Threading||Deeper threading may be serrated, some threads split near the tip and may have reverse threading near the head. Usually tapered threading near the tip and very sharp.||Sharp, shallow threads, not tapered toward the tip. Higher count/inch for hardwood than softwood screws, some have serrated threads too. Shank is typically smooth below the head.|
|Tip||Self-drilling and sharper||Flat tip or blunt for pre-drilling, or sharp for self-drilling|
|Shear Strength||Deck screws have greater shear strength than common wood screws.||Structural and lag screws have greater shear strength than wood or deck screws.|
|Pre-Drilling||Not usually necessary||Typically drilled for shank diameter|
|Cost||Range from 3 to 20-cents each depending on volume, size, metal, and type.||Range from 2 to 18-cents for wood screws, $0.60 to $1.25 for a lag screw or bolt, and 10 to 75-cents for structural screws. Cost per unit depends on length, gauge, metal, volume, type, and brand.|
What is the Difference Between Deck Screws and Wood Screws?
Telling deck screws apart from standard wood screws is a matter of knowing the differences and understanding how they affect the purpose of the two kinds of screws. Here’s a breakdown of the differences:
Deck screws are commonly coated or treated high tensile steel in a variety of colors, or stainless steel while standard wood screws are softer bright steel, copper, brass, or stainless steel. Since steel is stronger than brass or copper, some steel wood screws are treated or colored to look like brass or copper screws.
Deck screws are made for use outdoors and are treated with ceramic, zinc, or other material to prevent corrosion, or they are stainless steel which is highly resistant to corrosion. Standard wood screws typically are used indoors or where they are protected from the elements and aren’t corrosion-resistant unless they are stainless steel.
Most deck screws have a larger flat head and bulging cone-shaped underside or throat to help prevent them from being countersunk. Standard wood screws have a narrower flat head and a more tapered cone-shaped underside to make it easier to set into the wood. Wood screws also come with pan, oval, and washer heads for different uses.
Drive types for deck screws are commonly x or Philips, square or Robertson, star or Torx, or hex head for use with a wrench. The multiple contacts provided by the drive types permit more torque to be used when driving. This allows drills or other mechanical drivers to be used without fear of stripping the screw head.
Standard wood screws were typically a slotted or flathead drive type which limited the amount of contact with the driver, and thus the amount of torque. This made and makes it difficult to drive unless into predrilled and countersunk holes, thus reducing the risk of splitting the wood. Unfortunately, they are difficult to drive by hand, let alone mechanically, and very easy to strip, so many modern wood screws are now available with Philips or Robertson-style drives.
The shank of a standard wood screw is unthreaded and smooth, and it’s the diameter the pilot hole should be. The length of the shank makes the screw longer and makes it easier to pull the two pieces of wood together. On deck screws, the shank is often thicker than a wood screw to handle more torque and provide greater shear and holding strength. Some deck screws have reverse threading on the shank for better gripping, and others are smooth like standard wood screws.
The threads on standard wood screws spiral from the tip to the shank. The angle and number of threads per inch vary for use with different wood types. There are more threads per inch for hardwood to prevent splitting and less for softwoods. The thread is sharp but not as deep as those on deck screws, and some are serrated so predrilling isn’t necessary. Threads on deck screws are typically deeper to provide greater gripping power. Both types of screws offer threads of different pitches or angles too.
Deck screws usually have a sharp self-drilling tip; they may be slightly tapered or even split for faster driving. Standard wood screws typically require a pilot hole, so the tip may be blunt. Some wood screws have a sharp point for self-drilling but aren’t common in cabinetry or furniture making.
Deck screws are made of higher-grade steel than standard wood screws so are more durable and can withstand greater torque and don’t require predrilling. Standard wood screws are of a softer metal with less shear strength, they are designed to clamp two pieces of wood together, not handle other stresses.
Deck screws are for exterior use to fasten deck or fence boards to framing, building garden boxes, outdoor furniture, or other items. Standard wood screws are used to make indoor furniture and cabinetry where they clamp and hold two pieces of wood together. They are also used to mount hardware such as hinges.
The cost varies with volume purchases and the type of metal for both screw types. Deck screws commonly have a greater unit price compared to standard wood screws due to the stronger metal used to make them and the corrosion-resistant coating. Depending on size, gauge, and brand, a deck screw ranges from 3 to 20-cents a unit, and standard wood screws 2 to 18-cents a unit.
Are Deck Screws Structural?
Deck screws are not classed as structural screws, they are used to fasten and hold deck boards or fence boards to framing pieces, or other light construction uses. Structural screws are thicker and heavier, and designed to bear greater loads and fasten heavier structural members together.
Wood Screws vs Metal Screws
Wood screws are commonly used to join two pieces of wood together or to fasten hardware to wood. Metal screws are typically used to fasten metal, plastic, or wood to metal. Metal screws are threaded from tip to head, while wood screws have an unthreaded shank between the threading and head.
Metal screws are made of harder metal and are either self-tapping for predrilled holes or self-drilling with a sharp tapered tip. Both types of metal screws have strong sharp tighter pitched threads that cut into metal, wood, or plastic to draw and hold pieces together with a better grip. Wood screws are made of softer metal and have shallower threads made to cut into the sides of pilot holes and pull two wood pieces together.
Metal screws commonly have a slot, x, or a hex-head for driving, some even have a combination of drive options. Standard wood screws commonly have a slot, x, or square drive option. Metal screws can be used to fasten wood together, but are a more expensive choice.
Wood Screws vs Construction Screws
Construction screws, like deck screws, are a type of wood screw. They have a deep, notched, or serrated thread that spirals from the tip half or two-thirds up the screw’s length, and a smooth shank the rest of the way to the head. The transition between thread and shank is often textured to anchor the screw better.
Wood screws are commonly 1/4″ to 3” in length, while construction screws range from 3” to 12.5” in length. Construction screws are usually a heavier gauge and stronger metal than standard wood screws, so are stronger and more durable, and can handle greater torque. Many construction screws are also treated or coated to improve resistance to corrosion.
Most wood screws have a flat head with a narrow cone-shaped throat, construction screws often have a bulged or reinforced neck and may have a flat or washer style head. Construction screws frequently need star or Torx, square, or x drivers, although some are hex-headed for wrench driving while standard wood screws are slot, x, or square drives.
Best Deck Screws
Of the hundreds of deck screws on the market, we select two of the highest-rated to review.
Best Wood Screws
Selecting the best wood screw depends on the task it’s needed for. Wood screws fall into six broad categories: standard wood screws, deck screws, pocket hole screws, drywall, structural, and even lag screws. So, selecting the best is a matter of use.
Someone building fine furniture or cabinetry will select something different from someone fastening a ledger board to a home or doing rough carpentry. The two we’ve selected are general or all-purpose wood screws, they can be used for a variety of projects, both indoors and out.
Deck screws are a type of wood screw designed for outdoor use fastening deck boards, fence boards, railings, and other wood members to framing, or to make outdoor furniture. The self-boring tip draws well and the deeper thread bites into the wood around it to pull and hold. The screws are coated against corrosion and are made of more durable metal.
Standard wood screws aren’t coated and typically require pilot holes, have shallower threads, and are made of softer metal. They work well for clamping or holding two wood pieces together, or for mounting hardware to wood. Hopefully, you have a better understanding of the differences and potential uses of wood screws and deck screws for use in your projects.