Installing a wood fence around your property can increase privacy, security, and curb appeal. However, choosing the right screws is crucial for building a fence that stands the test of time.
The wrong screws can fail prematurely, causing loose boards, sagging posts, and costly repairs down the road. Pressure-treated lumber, outdoor weathering, and the sheer size of fence structures put heavy demands on screws.
In this article, we’ll explore the specialized screws engineered to handle everything fencing throws at them. We’ll compare corrosion-resistant coatings, materials, and features to match the best screws to your wood type and fence design.
Screws for Pressure-Treated Wood
Pressure-treated lumber contains preservative chemicals to resist decay and insect damage. The treatment process forces the preservatives deep into the wood under high pressure.
Standard screws corrode over time when used in these treated boards. As they deteriorate, their holding strength declines, eventually failing altogether.
Epoxy-Coated Deck Screws
Epoxy-coated deck screws stand up to constant weathering as well as pressure-treated wood’s corrosive properties. An epoxy coating resists moisture, sealing out water that causes oxidation (rust).
The coating also provides a smooth surface that won’t adhere to wood fibers. This prevents seizing up, allowing easy removal or adjustments years later.
Stainless Steel Screws
Stainless steel fence screws deliver comparable corrosion resistance. Stainless alloys like stainless steel 304 and 316 have sufficient chromium to resist rust despite outdoor exposure over years of service.
The downside is stainless steel lacks grip compared to carbon steel. Pre-drilling is recommended when driving stainless screws to prevent camming out damage and stripped screw heads.
Screws for Cedar & Redwood Fences
Western red cedar and redwood contain natural oils, resins, and extractives. These organic compounds make the woods naturally decay-resistant but cause standard screws to corrode.
Stainless Steel
As with pressure-treated lumber, stainless steel is the best screw choice to pair with these oily woods. The stainless alloy composition is impervious to the wood’s moisture and Extractives.
Brass and bronze screws offer some corrosion resistance. However, stainless steel has higher shear and tensile strength crucial for structural joints.
Structural Wood Screws
Structural wood screws are engineered for strength critical structural applications. While resembling standard screws, they provide around 50% higher shear and pullout strength.
Load Demands
Structural screws shine when fence demands are high. Tall privacy fences, heavy post-and-rail assemblies, and solid horizontal planking all carry big wind, gravity, and lateral loads.
TimberLok, Spax T-Star Plus, and Grabber Structural screws stand up to shear stress, withdraw loads, and challenging weathering in these robust outdoor structures.
Large Fence Hardware
Another structural screw benefit is large #14 and #15 shank diameters. These provide more threads to grip thick structural posts and horizontal plank lumber often used in fencing.
The large hex flange heads draw planks tightly together while preventing spinning off-angle during power driving.
Lag Screws for Sturdy Fence Posts
Lag screws are heavy-duty for securely fastening structural lumber under load. Standard diameters range from 1/4″ to 5/8″ to accommodate huge shear and tensile demands.
Hex Heads & Large Shanks
The large hex washer head prevents spinning while installed snugly against wood. Meanwhile, aggressive shank threading delivers powerful holding strength with just a standard socket wrench.
Keeping fence posts from loosening over decades outdoors is no small task. But burly lag screws stand up to years of wind, rain, and gravity trying to topple tall post assemblies.
Preventing Loose Fence Posts
Following best practices, predrilling appropriately sized pilot holes prevents wood splitting while allowing lag screws to seat fully. For detailed steps, see our guide on Reinforcing Fence Posts with Lag Screws.
Roofing Nails for Fence Boards
You might not expect rugged roofing nails in fencing, but they have unique advantages for installing fence boards. Roofing nails have an electrogalvanized coating and specialized diamond tip point.
Superior Penetration
The diamond shape point penetrates extremely dense pressure-treated boards better than smooth fine-thread screws. Even exotic hardwoods often used for fencing are no match for the extremely sharp diamond tip.
Combined with annular ring shank under the head, roofing nails resist pulled loose by wood movement, impact, and gravity better than screws. Once seated, these nails stay put.
Tested for Durability
While electrogalvanized zinc coatings don’t match stainless steel for corrosion resistance, roofing nail coatings still provide excellent longevity in exterior environments.
Testing standards like ASTM F1667 ensure roofing nails endure outdoor UV exposure, water immersion, humidity, and accelerated corrosion testing.
Matching Screws to Wood Density
Softwoods like pine, cedar, and fir have a lower density than hardwoods. Their low density cellular structure requires smaller, less coarse-threaded screws. Massive structural screws cause unsightly surface crushing, tear-out, and wood splits in low-density softwoods.
Alternatives for Softwoods
Drywall screws offer smooth shanks and fine threading suitable for softwoods’ density. Their ultra-sharp tips minimize tear-out damage while sinking heads flush.
Finish screws also work well in wood fencing made from low-density lumber. Just ensure electrogalvanized or other exterior grade finish for outdoor service.
Extra Thought with Hardwoods
Brazilian walnut, cumaru, ipe and other dense exotic hardwoods need precise pilot holes sized for each screw diameter. Tough lignin cell structure causes dense hardwoods to split, crack and snap screw heads without pre-drilling.
Rule of thumb: Pilot holes should equal screw diameter size minus 1/3. A 5/16″ hardwood deck screw needs a 7/32″ pilot hole accordingly.
Comparing Corrosion-Resistant Coatings
From coastal climates to high altitude mountain frost zones, environment drives the need for corrosion-resistant wood screws appropriate for your area.
Zinc
Electroplated zinc coatings deter red rust oxidation for several years in mild climates. Zip and self-tapping exterior screws feature electroplated zinc suitable for moderate humidity and precipitation.
Stainless Steel
We’ve covered stainless steel screws already, but it’s worth noting the exceptional corrosion resistance surpassing any other plating. Grade 316 stainless steel thrives in adversarial conditions like offshore marine applications.
Weather Resistance Testing
Spax, Simpson Strong-Tie, and other premium deck screw brands use neutral salt spray (NSS) testing to validate real-world corrosion prevention. This accelerated testing indicates years of expected resistance to oxidation failure.
Screw Grades & Standards
Structural screw compliance ensures they meet strict tested criteria before getting approved for structural building applications.
ANSI/ASME Standards
Grade specification standards like ANSI/ASME B18.6.1 dictate production quality controls, material strength, thread dimensions, and testing procedures.
ANSI 2 and ANSI 5 Buffalo Screws specifies heat treating and production checks that qualify structural building suitability.
Shear & Tensile Strength
Two key metrics indicate load-handling capability: shear strength and tensile strength. Both involve technical materials testing to quantify force tolerances before screw failure or tear-out.
Look for shear strength over 60,000 PSI for confident structural joint integrity under extreme fence demands.
Automated vs. Manual Installation
While power drivers speed fence building, hand-driven screws allow precision and care in special cases.
Power Screwguns
Cordless power drills and dedicated screwguns quickly drive screws consistently straight and at proper depth. This prevents uneven board alignment or dangerous points protruding where not intended.
Power driving embeds screw threads deeper within the wood’s natural grain compared to manual turns with a basic screwdriver.
Hand Screwing
Some applications warrant carefully controlled hand installation. Pre-drilling pilot holes and slowly advancing screws prevents structural lumber from cracking. The gentle approach also keeps screws tracking straight without veering off-angle from excessive torque.
Hand installation allows precision placement of screws into exact predetermined studs or structural members behind finished surfaces.
From sturdy privacy fence posts to horizontal planks battering wind, rain, and sun year after year, the right screws endure it all.
Knowing the engineered options for structure, corrosion resistance, traits of wood types, and installation methods results in durable, long-lasting wood fences.
Choosing appropriate screws is just as important as quality wood selection itself. Now you can build confidently with screws made to last decades like your pride and joy wood fence surrounding your property.
