Structural Screws vs. Lag Bolts: What's the Difference?

This image depicts a FastenMaster LedgerLOK being used to attach a wooden board to a concrete wall.

Nav­i­gat­ing con­struc­tion fas­ten­ers can be chal­leng­ing for pro­fes­sion­als and new­com­ers alike, espe­cial­ly when decid­ing between struc­tur­al screws and lag bolts. How­ev­er, under­stand­ing their dif­fer­ences is cru­cial for main­tain­ing a structure’s integrity. 

This guide dives into the dif­fer­ences between struc­tur­al screws and lag bolts to help builders and remod­el­ers choose the cor­rect fas­ten­er for each project. 

Understanding Structural Screws

Struc­tur­al screws rep­re­sent a sig­nif­i­cant advance­ment in fas­ten­ing tech­nol­o­gy that com­bines tra­di­tion­al screw attrib­ut­es with enhanced per­for­mance for mod­ern con­struc­tion demands. These fas­ten­ers boast high shear and ten­sile strength, which makes them ide­al for load-bear­ing applications. 

Their design fea­tures include self-start­ing tips and spe­cial­ized thread­ing for quick, pre-drilling-free instal­la­tion in dense mate­ri­als and advanced coat­ings for supe­ri­or water and cor­ro­sion resistance.

The key fea­tures of struc­tur­al screws include:

  • Code Com­pli­ance: They are designed to meet rig­or­ous build­ing codes and safe­ty stan­dards for reli­able use in struc­tur­al applications.
  • Inno­v­a­tive Design: Engi­neered head designs and dri­ve sys­tems ensure a strong hold, flush fin­ish and effi­cient installation.
  • Mate­r­i­al Ver­sa­til­i­ty: Struc­tur­al screws are capa­ble of fas­ten­ing a broad range of mate­ri­als, includ­ing wood, cer­tain met­als and composites.
  • Dura­bil­i­ty: Advanced coat­ings enhance longevi­ty to pro­tect against envi­ron­men­tal wear and corrosion.
  • Cost-Effec­tive­ness: Their effi­cien­cy and labor-sav­ing qual­i­ties can lead to over­all project cost savings.

These attrib­ut­es make struc­tur­al screws a ver­sa­tile and reli­able choice for builders and remod­el­ers seek­ing to opti­mize struc­tur­al integri­ty and project efficiency.

Understanding Lag Bolts

Lag bolts, or lag screws, have a long his­to­ry dat­ing back to their use in ship­build­ing that show­cas­es their endur­ing strength and reliability. 

Today, they play a cru­cial role in var­i­ous con­struc­tion projects, such as fram­ing hous­es and build­ing decks, due to their stur­dy build and abil­i­ty to sup­port heavy loads. While root­ed in tra­di­tion, lag bolts have adapt­ed to meet mod­ern require­ments by com­bin­ing his­tor­i­cal resilience with con­tem­po­rary versatility.

Their mod­ern appli­ca­tions include: 

  • Deck Con­struc­tion: Lag bolts are a pre­ferred choice for con­struct­ing decks because they sup­port heavy loads and pro­vide a secure and durable attach­ment between deck frames and wood­en posts.
  • Struc­tur­al Sup­port: Their appli­ca­tion extends to secur­ing struc­tur­al beams and posts in res­i­den­tial and com­mer­cial build­ings, where the integri­ty of the con­struc­tion is paramount.
  • Out­door and Heavy Tim­ber Projects: Thanks to var­i­ous fin­ish­es and mate­ri­als, lag bolts are well-suit­ed for out­door use by resist­ing cor­ro­sion and wear in harsh environments.

Structural Screws vs. Lag Bolts

While lag bolts are known for their strength, struc­tur­al screws now offer a com­pa­ra­ble or even supe­ri­or ten­sile strength.

Struc­tur­al screws stream­line instal­la­tion and usu­al­ly elim­i­nate the need for pre-drilling, which makes them a time-sav­ing choice in fast-paced construction.

They are also com­pat­i­ble with a wider range of mate­ri­als, includ­ing mod­ern com­pos­ite deck­ing, which adds ver­sa­til­i­ty to their strength.

When decid­ing between lag bolts and struc­tur­al screws, think about your pro­jec­t’s needs: the weight it must bear, the mate­ri­als used and the envi­ron­ment it will be in.

Lag bolts are great for heavy-duty jobs due to their strength and proven track record. Struc­tur­al screws, on the oth­er hand, are a new­er tech­nol­o­gy that pro­vides sim­i­lar strength but with eas­i­er instal­la­tion and com­pat­i­bil­i­ty with var­i­ous materials.

Innovative Applications and FastenMaster Solutions

Fas­ten­Mas­ter has a wide range of prod­ucts suit­able for an array of applications. 

ThruLOK

This image depicts a FastenMaster ThruLOK system being drilled into wooden boards.

The Fas­ten­Mas­ter Thru­LOK sys­tem offers a robust alter­na­tive to tra­di­tion­al through-bolts, com­bin­ing the strength of a bolt­ed con­nec­tion with the ease of a screw. 

It’s per­fect for tasks like join­ing deck posts to rim joists or fix­ing beams to posts with­out the need for pre-drilling, sav­ing time and costs. With its no pre-drilling fea­ture and a gal­va­nized coat­ing that meets treat­ed wood code require­ments, Thru­LOK stands out as a top choice for projects need­ing fast, stur­dy and code-com­pli­ant solutions.

HeadLOK

This image depicts a black wood screw being drilled into a piece of plywood.

The Head­LOK sys­tem is a strong wood screw that replaces the need for ⅜‑inch lags and can tack­le heavy-duty tasks with­out the need for pre-drilling. 

With its inter­nal dri­ve and flat head design, it deliv­ers supe­ri­or shear strength com­pared to sim­i­lar options and is approved for ACQ and code compliance. 

Ide­al for struc­tur­al deck fram­ing, it’s sim­ple instal­la­tion and sleek black flat­head design guar­an­tee a neat fin­ish for any project. 

LedgerLOK 

This image depicts a FastenMaster LedgerLOK being used to attach a wooden board to a concrete wall.

The Ledger­LOK sys­tem is engi­neered to secure­ly attach deck ledgers to hous­es. It replaces ½‑inch lag screws or through bolts to sim­pli­fy instal­la­tion while also main­tain­ing strength. 

Test­ed for exte­ri­or use com­pli­ance, Ledger­LOK is built for long-last­ing per­for­mance out­doors. Its design enables easy dri­ving with­out pre-drilling, which is an effi­cient solu­tion for pros and DIYers. 

FlatLOK 

This image depicts a hand drill drilling a red screw into a piece of plywood.

The >Flat­LOK sys­tem is a ver­sa­tile solu­tion for con­nect­ing mul­ti-ply LVL, LSL and PSL beams, gird­er truss­es and heavy-duty applications. 

It removes the need for pre-drilling, reduc­ing instal­la­tion time and labor costs sig­nif­i­cant­ly. Its unique low-pro­file head design pro­vides a clean, visu­al­ly appeal­ing fin­ish while main­tain­ing strength. Test­ed for full code com­pli­ance, Flat­LOK is per­fect for ensur­ing dura­bil­i­ty and safe­ty in essen­tial struc­tur­al connections. 

Choose Innovation and Strength With Structural Screws by FastenMaster

At Fas­ten­Mas­ter, our com­mit­ment to inno­va­tion, qual­i­ty and cus­tomer sat­is­fac­tion sets us apart in the fas­ten­er indus­try. Our ded­i­ca­tion to devel­op­ing solu­tions that enhance the dura­bil­i­ty and effi­cien­cy of con­struc­tion projects can be seen in our rig­or­ous test­ing and adher­ence to high standards. 

Choos­ing Fas­ten­Mas­ter for your struc­tur­al screw needs means part­ner­ing with a leader in con­struc­tion fas­ten­ing sys­tems. Our inno­v­a­tive prod­ucts are designed to sim­pli­fy instal­la­tion process­es with unmatched strength and durability. 

Whether you’re a pro­fes­sion­al con­trac­tor or a DIY enthu­si­ast, our struc­tur­al screws are craft­ed to meet your pro­jec­t’s unique demands by ensur­ing both safe­ty and efficiency. 

Con­tact us today for more information!