Premium fence materials, what they are and how to check them

What premium fence materials actually mean

Premium fence materials are the ones chosen to resist what actually destroys fences: decay at the ground line, rust, wire stretch and gate sag. The word has no legal definition on a quote, so it only means something when it points to specific, checkable things such as a ground contact rating on the post tag, a stated wire gauge and galvanizing class, and fasteners rated for the wood they go into.

Solid Rock Fencing builds with high quality premium materials. We do not name grades or brands on this page, and we are not going to hide behind the word either. Below is what premium means piece by piece, and the questions that tell you whether a contractor is using it. Ask us the same questions. The answer should be a list, not an adjective.

One point first. Material is only half of a fence that lasts. A premium post set badly will lean, and an average post set well will often outlast it. We cover that in its own section below.

Posts and ground contact ratings

A fence post lasts as long as the wood in the ground allows, and a post rated for ground contact is the minimum for a fence you want to keep. Decay concentrates at the soil line, where moisture meets air, and long-term post tests from the USDA Forest Service and Ohio State both recorded failures from decay at or near grade.

What the end tag tells you

Treated posts should carry an end tag. The American Wood Protection Association says the tag should show AWPA U1, the use category, the preservative name and retention in pounds per cubic foot, and the manufacturer. If the wood has no AWPA U1 mark and no use category, it probably does not meet AWPA standards. Use categories relevant to fence work are:

• UC3B. Exterior above ground, uncoated or poor runoff, such as fence pickets and railings.
• UC4A. Ground contact, general use. This covers fence posts in normal conditions.
• UC4B. Ground contact for heavy duty use, higher decay potential or hard-to-replace parts.
• UC4C. Critical structural, severe decay.

So premium ground contact generally means UC4B, a stated higher retention, or a naturally durable species. A Journal of Light Construction article by a Forest Products Laboratory researcher recommends UC4B for harsh, wet or high-decay sites, while UC4A should be fine in many ordinary cases. Whether a supplier sells UC4B fence posts is a question for the buyer to ask, and that is why we say ask.

Watch for these post problems

• Thin lumber in the ground. Treated lumber two inches thick or less may be treated only for above-ground use.
• Treated to refusal. The Forest Service treated wood guide says to avoid wood treated to refusal.
• Unlabeled landscape timbers. University of Georgia says these are often not treated for ground contact.
• Cut or drilled treated posts. Cuts, notches and holes expose untreated interior wood. Field cuts should be dressed, and the Journal of Light Construction names copper naphthenate containing at least 1 percent elemental copper.

Naturally durable species

Some wood resists decay without preservative, but only the heartwood does. Sapwood of even the best species rots fast. The Forest Products Laboratory lists heartwood of cedars, junipers, redwood, black locust, osage orange and several oaks as resistant or very resistant. Purdue Extension adds that black locust sapwood had completely deteriorated at the ground line in its observations, and that heartwood from young, fast-grown trees may be less resistant.

University of Georgia gives untreated life figures of 20 to 25 years for black locust and osage orange and 15 to 20 for red cedar, against 3 to 7 for untreated pine. That table comes from Georgia, and we cannot confirm how it applies to Ohio and Pennsylvania soil. The practical question for any durable-species quote is how much sapwood each post contains.

Post size matters too. University of Georgia puts corner and gate posts at least 8 inches across the top and brace posts at 5 inches or more. Penn State notes that round posts are stronger than square posts of similar size.

Rails and boards

A rail has two jobs, staying straight and staying attached, and thin rails fail at both. University of Georgia notes that wood rails are usually nominal 1 by 6 or 2 by 6, and that 1 by 6 costs less but warps more and is weaker. For a fence that has to hold livestock or stay straight over long spans, thicker rails are the premium choice.

Species and finish matter. Virginia Tech notes that rough-cut oak is hard and horses dislike chewing it, but unseasoned oak warps and rots faster at post-board joints. It also notes that treated pine looks finished, resists rot and discourages chewing, but needs thicker boards, and its treatment wears off over time. Rough-sawn boards take penetrating stain better and hold the finish longer than smooth planed wood, according to the USDA finishing handbook. Our fence painting and staining page covers finishing in detail.

A claim about kiln-dried versus green boards deserves caution. Dry lumber is 19 percent moisture or less, and drying wood is prone to warp and check. We found no extension study comparing the two for fence boards, so we will not claim an advantage.

Fasteners, nails and staples

Rust is the quiet failure. A fence can have perfect posts and still lose boards because the nails corroded. Preservatives used in treated wood can be corrosive to metal, so the fastener has to match the wood. The wood-treatment industry recommends hot-dip galvanized nails meeting ASTM A153 Class D, or type 304 or 316 stainless, and screws with a rating for the preservative.

Simpson Strong-Tie, a connector maker, recommends stainless steel where preservative-treated wood is used in ground contact. University of Georgia says all fasteners should be galvanized, preferably Class 3, and lists grooved-shank nails and galvanized screws for boards. Wire staples should be 8 or 9 gauge, hot-dip galvanized, 1.75 to 2 inches long, and never shorter than 1.5 inches. The Forest Products Laboratory warns that iron nails rust and stain wood. A quote that just says nails or screws does not tell you any of this.

Woven wire gauge and galvanizing

For wire, premium means heavier gauge, thicker zinc and a fence built to hold tension. A lower gauge number means thicker wire. Ohio NRCS specifies standard woven wire with top and bottom wires 10 gauge or heavier, intermediate wires and stays 14.5 gauge or heavier, stays no more than 12 inches apart, and staples 9 gauge. University of Georgia says horse mesh should be at least 12.5 gauge unless it is high-tensile.

Galvanizing is the zinc coating that fights rust. Class 1 has the lightest coating and Class 3 the heaviest, roughly two to three times as much. University of Georgia says Class 3 galvanizing can easily add 5 to 10 years of life to fence wire in a humid climate like Georgia's. Red Brand, a wire maker, claims about 2.5 times the life of Class 1 for its Class 3 product, and its own page says commercial grade has the least zinc and no ASTM minimum. Those are manufacturer claims, so we cite them as such. Ask what class the wire is. See our field and woven wire fence page for how wire fence is built.

Wire is only as good as the ends. Wire tension is carried by corners and ends. University of Georgia reports pull of about 3,000 pounds, rising to about 4,500 in winter cold. If the corner assembly moves, the wire loosens whatever its gauge.

Gate hardware

A gate is the moving part of a fence, so hardware and the gate post carry more risk than any other piece. A campus chain link specification from Michigan State calls for structural steel hinges, stops, drop rods and keepers sized so hinges do not twist and the gate stays level. That is a general principle, not a gate dimension.

The gate post matters as much as the hinge. Frost can push a post out of the ground and the weight of a gate tips it further, according to Grainews. Penn State says corner and gate posts are about 25 percent larger than line posts and set about 48 inches deep. For horses, Penn State recommends tubular steel gates and avoiding diagonal cross-bracing on the gate itself, since it can trap legs and heads. Hinge nuts that adjust, so a gate can be leveled, are a useful feature, but we found no neutral source ranking one hinge type over another. See our gates page.

Setting posts matters as much as the material

A post only performs as well as its footing. Treated post life ranges in the published sources, 10 to 25 years from Penn State and 20 to 35 from Kentucky Extension, assume a post that stays upright and drained. A post that heaves, leans or sits in trapped water will not get there.

• Depth. Penn State gives a typical line post about 36 inches deep and corner and gate posts about 48. Local frost depth varies, from about 30 to 42 inches in the Ohio and Pennsylvania jurisdictions we checked, and the building office sets the number for your property.
• Backfill. University of Wisconsin Extension advises tamping in layers and using sand and gravel backfill in silt and clay, because freeze-thaw can push dug posts out.
• Concrete or not. Sources disagree. The Forest Products Laboratory says concrete that reaches the surface traps water against the post, and Wisconsin warns cement can hold moisture near the top. Other work found concrete fill outlasting gravel or dirt. The right setting depends on soil, post and drainage, so we do not claim one rule.
• Driven or set. University of Tennessee reports driven posts are 1.7 times as strong as tamped posts.
• Braces. Every corner, end and gate on a wire fence needs a brace assembly. See fence repair for what happens when they fail.

Side by side, what to check for each part

This table is a buying checklist, not a ranking of brands. Any answer should name the item, a number or a standard.

How to check a quote and what to ask any contractor

A quote worth trusting lists materials by type and size, not by adjective. Compare the same lines on every quote, and be suspicious of the quote that is much lower or has fewer lines. Our how estimates work page explains what a clear written estimate contains.

1. Ask for the material listPosts, rails, boards, wire, fasteners, gates and hardware, each with size and rating.
2. Check the post tagLook for AWPA U1, a use category such as UC4A or UC4B, the preservative, and a retention figure.
3. Ask about depth and bracingHow deep are line posts and corners, and how are corners and gates braced?
4. Ask about fasteners and wireWhat nails and staples, and what wire gauge and galvanizing class?
5. Ask how long since treatmentFresh treated wood is wet. If you plan to finish it, see our painting page.
6. Check the warranty termsRead what it covers and does not. See our warranty.

Myth versus fact

Premium materials at Solid Rock Fencing

Solid Rock Fencing builds with high quality premium materials. We do not publish grades or brands here, because the honest way to judge premium is to see the actual list for your fence. The list changes with the job. A horse fence, a wire pasture fence, a privacy fence and a gate each need different parts.

What you can expect from us is the same kind of answer this page asks you to demand from anyone. Specific materials, in writing, with the setting and bracing described. We also offer a 10 year workmanship warranty, covering defects in workmanship and not weather, impact, animals or normal wood aging, with written terms in the estimate. The warranty covers our work. Material choices cover the rest, and the rest is where premium helps.

When you request a FREE estimate, ask for the material list. We will go through it with you, post by post and part by part.

Questions we hear