Screw Types for Decking: Which to Use?

Cre­at­ing a stun­ning deck that will expand liv­able space in a home and give home­own­ers the con­nec­tion to the out­doors requires choos­ing the right deck­ing com­po­nents, from the type of deck­ing down to the screws and fas­ten­ers used to hold the deck together.

Every com­po­nent must be care­ful­ly cho­sen for dura­bil­i­ty, ease of use, cost and longevi­ty. There are almost as many types of fas­ten­ers as there are types of deck­ing, but this guide will help you choose the right deck­ing screws for any deck­ing project. 

Importance of Choosing the Right Screws

Safe­ty, dura­bil­i­ty and aes­thet­ic val­ue are all fac­tors that go into choos­ing the right deck­ing screws for a project. Deck­ing screws should be cor­ro­sion-resis­tant so that they won’t fail under wet weath­er con­di­tions or in extreme climates.

The thread design of the screw also mat­ters because if you choose deck­ing screws that don’t have prop­er head design and length, the screws won’t have the grip and secu­ri­ty need­ed to keep the screws from loos­en­ing over time.

When deck builders and con­trac­tors don’t use the right deck­ing screws, home­own­ers can end up fac­ing cost­ly repairs or a deck that los­es struc­tur­al integri­ty after a short time. Builders that take pride in their work and rep­u­ta­tion know that using the right deck­ing screws to build a deck is essen­tial to build­ing a deck that will last and com­plete home­own­er satisfaction.

Impact on Deck Durability

Struc­tur­al screws that are designed for deck­ing are excep­tion­al­ly strong and made to with­stand extreme weath­er, foot traf­fic, and the weight of fur­ni­ture, grills and oth­er items cus­tom­ar­i­ly used on decks. 

Ordi­nary screws, even those used suc­cess­ful­ly in oth­er build­ing projects, aren’t strong or durable enough to be used for build­ing decks.

Safety Considerations

Choos­ing the right deck­ing screws is also a mat­ter of safe­ty for your crew and the homeowners. 

Using screws that aren’t designed for deck­ing or that aren’t strong enough to hold a deck togeth­er puts your crew at risk of deck­ing com­ing loose and caus­ing acci­dents on the job site. You don’t want your crew mem­bers injured and out of work because the wrong mate­ri­als were used for the job.

If the screws used aren’t the cor­rect screws for the deck­ing mate­r­i­al, they won’t have the strong bond nec­es­sary to make the deck safe for peo­ple to use. Even if the screws seem to tight­en at first, over time, they will loosen and make the deck unsafe.

Types of Decking Screws

When choos­ing the right deck­ing screws, the first thing that you need to con­sid­er is the mate­r­i­al of the screw. Dif­fer­ent types of deck­ing screws have var­i­ous ben­e­fits and are best used with spe­cif­ic types of deck­ing materials.

Wood Decking Screws

Wood deck­ing screws are spe­cial­ized fas­ten­ers care­ful­ly designed to secure­ly attach wood deck­ing boards to the under­ly­ing deck frame­work. Unlike tra­di­tion­al screws, wood deck­ing screws have sharp self-drilling tips and thread­ing designed to pre­vent split­ting in wood. The design also gives the screws a tighter grip.

Wood screws are typ­i­cal­ly used with any nat­ur­al wood deck­ing mate­ri­als, includ­ing pres­sure-treat­ed lum­ber. The most sig­nif­i­cant ben­e­fits of using wood screws include:

• Excep­tion­al Dura­bil­i­ty: Wood screws are very resis­tant to cor­ro­sion. They are a smart choice for wood decks and rail­ings locat­ed in wet cli­mates or areas with extreme tem­per­a­tures, big swings in tem­per­a­ture in the sum­mer and win­ter, and out­door appli­ca­tions where the wood will have high UV exposure.
• Secure Fas­ten­ing: The deep thread­ing and sharp tips of wood screws are per­fect for cre­at­ing a secure hold in wood deck­ing mate­ri­als, reduc­ing the risk of board move­ment, squeaks or insta­bil­i­ty over time.
• Ease of Instal­la­tion: Self-drilling wood screws min­i­mize the need for pre-drilling, which can mean faster instal­la­tion for your crew and low­er costs for you. 

Composite Screws

Com­pos­ite deck­ing screws are deck fas­ten­ers best suit­ed for installing com­pos­ite deck­ing mate­ri­als. These screws are made to work with com­pos­ite boards and their unique prop­er­ties like flex­i­bil­i­ty and ther­mal expan­sion and contraction. 

If you’re build­ing a deck using com­pos­ite boards, you should use com­pos­ite deck­ing screws because they are designed for:

• Split and Crack Pre­ven­tion: Com­pos­ite deck­ing screws have unique thread designs and cut­ting tips specif­i­cal­ly designed to work with com­pos­ite boards that reduce the risk of mush­room­ing or dam­ag­ing the mate­r­i­al dur­ing instal­la­tion, even near the board edges.
• Clean Fin­ish­es: Com­pos­ite deck­ing screw heads can be col­or-matched to blend seam­less­ly into com­pos­ite deck­ing boards. They also have coun­ter­sink­ing pro­files for a flush appear­ance that doesn’t detract from the aes­thet­ic appeal of the boards.
• Cor­ro­sion Resis­tance: Coat­ed or stain­less-steel com­pos­ite screws resist cor­ro­sion and stain­ing, so they are durable and safe to use in any type of climate.

Differences from Wood Screws

Com­pos­ite screws have fin­er thread­ing and dis­tinct cut­ting tips made to work per­fect­ly with the dense syn­thet­ic tex­ture of com­pos­ite deck boards so that they don’t split or crack the boards.

They have reverse threads near the head to pull the mate­r­i­al down tight­ly, elim­i­nat­ing mush­room­ing on com­pos­ite sur­faces. Com­pos­ite screws can also have col­or-matched, low-pro­file heads for a clean, flush fin­ish that blends with the com­pos­ite deck­ing material.

Stainless Steel Screws

Stain­less steel deck­ing screws are high-per­for­mance deck fas­ten­ers made from cor­ro­sion-resis­tant stain­less steel. Their strength and resis­tance to rust and cor­ro­sion make them the ide­al deck fas­ten­ers for decks in coastal or salt water climates.

Stain­less steel screws have sharp, self-drilling tips and threads engi­neered for secure fas­ten­ing in wood, com­pos­ite and hard­wood deck­ing. Stain­less steel screws main­tain struc­tur­al integri­ty over time and are avail­able in var­i­ous grades, such as 304 and 316.

They are the best choice for deck­ing projects where resis­tance to rust and cor­ro­sion is the most crit­i­cal fac­tor. They cre­ate a secure con­nec­tion and can keep decks strong even in extreme­ly wet areas.

Screw Size and Length Considerations

The mate­r­i­al of the screw is just one con­sid­er­a­tion that will impact the effec­tive­ness and strength of the screw’s abil­i­ty to hold. Choos­ing the right screw size and length is also nec­es­sary to cre­ate a high-per­for­mance deck that will stand up to weath­er and wear and tear.

General Sizing Guidelines

In gen­er­al, if the deck you’re build­ing is made from stan­dard wood or com­pos­ite deck­ing boards, screws should typ­i­cal­ly be 2.5 inch­es to 3 inch­es in length to make sure that they can go at least 1 inch into the deck boards.

Thick­er or hard­wood deck­ing may require screws up to 3.5 inch­es for secure attachment. 

Thick­er screws pro­vide greater strength for heavy-duty appli­ca­tions. For hid­den fas­ten­ers or pre-grooved boards, screw siz­ing should align with the sys­tem spec­i­fi­ca­tions. Choos­ing the cor­rect screw size is essen­tial to pre­vent issues like loos­en­ing, split­ting and com­pro­mised deck performance.

Factors Affecting Length Selection

The thick­ness of the deck­ing mate­r­i­al is just one of the fac­tors that should play a role in the length sec­tion of the deck­ing screws that are used on a deck build or rebuild. The deck type, load require­ments and envi­ron­men­tal fac­tors should also be con­sid­ered when choos­ing the length of deck screws.

Best Practices for Installation

Once you have cho­sen the right deck screws for a deck project, you should also always fol­low the instal­la­tion best prac­tices for the deck­ing screws and deck­ing mate­r­i­al that you’ve cho­sen, includ­ing using the right drilling equip­ment and prop­er torque set­tings dur­ing installation.

Pre-Drilling vs. No Pre-Drilling

Choos­ing between pre-drilling and no-pre-drilling deck screws depends on the deck­ing mate­r­i­al, the screw design and the project requirements.

Pre-drilling deck screws makes it eas­i­er for those screws to pen­e­trate dense mate­ri­als smooth­ly and with per­fect alignment.

Self-drilling screws elim­i­nate the need for pre-drilling. They save time and labor and are often used with soft­er wood deck­ing, pres­sure-treat­ed lum­ber deck­ing and com­pos­ite decking.

Proper Torque Settings

Instal­la­tion best prac­tices also include using the prop­er torque set­tings for the type of deck­ing fas­ten­ers you’ve chosen.

Prop­er torque set­tings for deck screws allow for secure fas­ten­ing with­out dam­ag­ing the deck­ing mate­r­i­al. Over-torquing deck­ing fas­ten­ers can strip threads, dam­age screws or cause inden­ta­tions in com­pos­ite or soft­wood decking. 

Over time, those inden­tions can make the deck look bad or com­pro­mise the struc­tur­al integri­ty of the fin­ished deck.

Under-torquing, on the oth­er hand, may result in loose screws and an unsta­ble deck. For soft­er mate­ri­als, start with a low­er torque set­ting and grad­u­al­ly increase until screws sit flush with­out over-sink­ing. In hard­er woods or com­pos­ites, mod­er­ate torque pre­vents split­ting or mushrooming.

Find the Right Decking Screws for Your Next Project

When search­ing for the per­fect screws for your next deck project, con­sid­er their mate­r­i­al, size and length. 

Then, take a look at FastenMaster’s full range of deck­ing solu­tions so that you can build decks you won’t wor­ry about stak­ing your rep­u­ta­tion on.