Metal roof trusses are steel trusses, usually welded angle iron or tube for pole barns, carports and garages, or cold-formed C-sections for houses, and a stock 30 ft steel gable truss listed at $330 to $620 at five US suppliers on October 18, 2026. Stock steel trusses are set 10 to 12 ft apart, so a 30 x 40 ft pole barn needs only 5 of them. The catch is the load rating: one widely sold stock truss is stamped for a 15 psf ground snow load, which many northern counties exceed.
This page covers steel trusses specifically. For wood truss types, spans and the truss vs rafter decision, start with our roof trusses guide.
By The Roofing Brief Team. Last reviewed: October 2026.
Key numbers at a glance
The figures most buyers of steel roof trusses need are the price per truss, the spacing, the load rating stamped on the drawing and the code limits. Each row below names its source. Retail prices are dated listings and can change without notice, and freight, tax and hardware may be extra.
| Metric | Figure | Source |
|---|---|---|
| 30 ft steel gable truss, stock 4/12 pitch | $330 to $620 each | Five supplier listings checked Oct 18, 2026 (table below) |
| Steel truss material price, national range | $150 to $700+ each (wood: $60 to $500) | HomeGuide, Jan 21, 2026 |
| Typical spacing for steel pole barn trusses | 10 to 12 ft on center (8 to 12 ft range) | Best Buy Metals; Lyon Metal Roofing; Buffalo River Truss |
| Trusses for a 30 x 40 ft barn at 10 ft spacing | 5 (40 / 10 = 4 bays, plus 1) | Roofing Brief arithmetic; Lyon Metal Roofing FAQ |
| Stock angle-iron truss design loads (one maker) | 20 psf roof live, 15 psf ground snow, 105 mph | Best Buy Metals product listing |
| IRC prescriptive limit for cold-formed steel roof framing | 40 ft span, 60 ft length, 3:12 to 12:12, ground snow 70 psf max | 2021 IRC R804.1.1 |
What are metal roof trusses?
Metal roof trusses are triangulated steel frames that carry a roof from wall to wall or post to post. Three families dominate: welded hot-rolled angle iron (the stock pole barn truss), welded tube or bar-joist style trusses (carports and wider ag buildings), and cold-formed steel C-section trusses screwed together for houses and multifamily work. They follow different design standards and suit different buildings.
The phrase also gets used for wood trusses that carry a metal roof. That is a spacing and purlin question, covered further down. The table sorts the steel types by what they are made of and where each one fits.
| Type | How it is built | Typical buildings | Typical spacing | Design standard | Source |
|---|---|---|---|---|---|
| Welded angle-iron gable or lean-to truss | 1-1/2 in or 2 in angle chords, 1-1/4 in angle webs, welded purlin cups, bolted apex | Pole barns, hay sheds, shops, ag buildings | 10 ft (8 to 12 ft by design) | Hot-rolled structural steel; one engineering sheet lists ASTM A36 | Best Buy Metals listing; Metal Roofing Wholesalers engineering sheet |
| Welded tube or bar-joist truss | Steel tubing or bar-joist chords, welded webs | Carports, riding arenas, wide-span barns | 8 to 12 ft | Engineered per project; stamped drawings | Lyon Metal Roofing; Buffalo River Truss |
| Cold-formed steel (CFS) truss | Roll-formed C-shaped members joined with screws, bolts or welds | Houses, multifamily, mid-rise roofs | 16 or 24 in (IRC table spacings) | 2021 IRC R804.3.6 (AISI S230, Section F6); IBC 2211 (AISI S240) | BuildSteel CFS truss guide; 2021 IRC |
Truss shape is a separate choice from material. Steel truss maker US Steel Truss lists Pratt, Warren, North Light, Fink, scissor, saw-tooth and bowstring designs, and its product line adds single slope and gambrel trusses. Ask a supplier which web pattern its stock trusses use.
How much do metal roof trusses cost?
Stock steel gable trusses listed at $219 to $420 for a 20 ft span and $430 to $770 for a 40 ft span at five US suppliers on October 18, 2026. HomeGuide’s January 2026 guide puts steel trusses at $150 to $700+ each for material. Prices exclude posts, purlins, panels, freight and labor, and the stock trusses listed are 4/12 gables, several with a stated 1 ft to 18 in overhang.
| Span (4/12 gable) | Wheeler Metals (OK, AR, MO) | SteelBarnTruss.com | Best Buy Metals (online shop) | Stroud’s Building Supply (NC) | Quality Outdoor Products (TN) |
|---|---|---|---|---|---|
| 20 ft | $219 | $306.64 | $342 | $385 | $420 |
| 24 ft | $247 | $330 | $371 | $462 | $520 |
| 30 ft | $330 | $360.64 | $452 | $577.50 | $620 |
| 40 ft | $430 | $600 | $568 | $770 | $630 |
Source: each supplier’s public price page or online store, checked October 18, 2026. Stroud’s 30 ft product page showed $525 on the same day while its price list showed $577.50, so confirm the price at order. The SteelBarnTruss.com list carries no date, and its gable truss figures largely match a price list that Armour Metals of Augusta, Georgia marks as effective September 21, 2021, so call before relying on it.
How much is a 30 ft metal truss?
A stock 30 ft steel gable truss at a 4/12 pitch listed at $330 (Wheeler Metals), $360.64 (SteelBarnTruss.com), $452 (Best Buy Metals), $577.50 (Stroud’s Building Supply) and $620 (Quality Outdoor Products) on October 18, 2026. Load ratings differ between these products, so the cheapest listing is only comparable if its stamped drawing covers your snow and wind loads.
Why steel trusses are priced by the foot
Several suppliers price steel trusses by linear foot of span, which makes quotes easy to compare. Stroud’s list works out to exactly $19.25 per ft at every stock length, and its custom formula adds $0.50 per ft for each pitch step above 4/12 plus $100 per truss. Dividing each 30 ft listing by 30 gives the comparison below.
| Supplier | 30 ft listed price | Price per ft of span | Shipping weight or note |
|---|---|---|---|
| Wheeler Metals | $330 | $11.00 | Category page lists price only |
| SteelBarnTruss.com | $360.64 | $12.02 | 22 purlin cups, 17 ft 4 in top chord |
| Best Buy Metals | $452 | $15.07 | 230 lb shipping weight |
| Stroud’s Building Supply | $577.50 | $19.25 | 2 in angle steel |
| Quality Outdoor Products | $620 | $20.67 | Listed as PB TRUSS 30 |
Source: supplier listings, October 18, 2026; price per ft is Roofing Brief arithmetic (listed price divided by 30).
What custom pitch and length add
A steeper pitch or an odd span usually moves a steel truss off the stock list and adds a per-truss fee and lead time. Stroud’s publishes its formula, which makes the arithmetic checkable: a 40 ft truss at 6/12 costs $910 there, versus $770 for the stock 4/12 truss, and custom orders typically take 6 to 8 weeks.
| Example (Stroud’s formula) | Arithmetic | Price |
|---|---|---|
| 40 ft gable, stock 4/12 | 40 ft x $19.25 | $770 |
| 40 ft gable, 6/12 custom pitch | 40 ft x ($19.25 + 2 steps x $0.50) + $100 | $910 |
| 23 ft gable, custom length | 23 ft x $20.25 + $100 | $565.75 |
| Change pitch or overhang (SteelBarnTruss.com) | $20 per truss for each change | +$20 |
Source: Stroud’s Building Supply custom truss page and SteelBarnTruss.com price list, checked October 18, 2026. Stroud’s states that sales are final on these products.
What a full steel truss roof kit costs
In one supplier’s published kit pricing, trusses are roughly a quarter of the cost of a steel pole barn roof package. Stroud’s Building Supply prices complete kits with its 2 in angle steel trusses at $8.99 per sq ft for a standing roof up to 40 ft clear span, so a 30 x 40 ft roof kit works out to about $10,788, of which 5 trusses at $577.50 are $2,887.50, or roughly 27%.
| Stroud’s kit (2 in angle steel trusses) | Price per sq ft | Minimum | Posts and truss spacing | 30 x 40 ft (1,200 sq ft) at that rate |
|---|---|---|---|---|
| Standing roof, up to 40 ft clear span | $8.99 | 900 sq ft | 6x6x16 posts, trusses at 10 ft | $10,788 |
| Enclosed building, up to 40 ft clear span | $13.49 | 1,200 sq ft | 6x6x16 posts, trusses at 10 ft | $16,188 |
| Standing roof, 50 ft clear span | $9.79 | 900 sq ft | 8x8x16 posts, trusses at 10 ft | Not applicable (50 ft span) |
| Standing roof, 60 ft clear span | $10.49 | 900 sq ft | 8x8x16 posts, trusses at 8 ft | Not applicable (60 ft span) |
Source: Stroud’s Building Supply pole barn kits page, checked October 18, 2026. Standing roof kits list posts, trusses, 2×6 yellow pine purlins, 29 gauge painted metal, ridge cap, trim and fasteners; enclosed kits add girts, reflective foil insulation and siding. The 30 x 40 ft totals and the 27% truss share are Roofing Brief arithmetic, before delivery, concrete and labor. Note how the wider kits step up to 8×8 posts and, at 60 ft, to 8 ft truss spacing.
Are metal trusses cheaper than wood?
Per truss, steel usually costs more than wood: HomeGuide lists a 30 ft wood truss at $120 to $330 and steel trusses at $150 to $700+. Per building, steel can come out even or cheaper on a pole barn because it is set 10 ft apart instead of 2 to 4 ft, so you buy fewer trusses. A house or attached garage rarely gets that benefit, because it still needs a ceiling and closely spaced framing.
The worked example below prices only the truss line for a 30 x 40 ft building. The truss count formula is building length divided by spacing, plus one.
| 30 x 40 ft building | Spacing | Trusses | Price per truss | Truss line total | Per sq ft of footprint (1,200 sq ft) |
|---|---|---|---|---|---|
| Stock steel gable truss | 10 ft | 5 | $330 to $620 | $1,650 to $3,100 | $1.38 to $2.58 |
| Wood truss, agricultural spacing | 4 ft | 11 | $120 to $330 | $1,320 to $3,630 | $1.10 to $3.03 |
| Wood truss, residential spacing | 2 ft | 21 | $120 to $330 | $2,520 to $6,930 | $2.10 to $5.78 |
Source: steel prices from the five October 2026 listings above; wood prices from HomeGuide’s 30 ft wood truss range (January 2026); the 2 ft residential and 4 ft agricultural spacings are those stated on a 30 ft common truss listing at AW Graham Lumber (Kentucky). Totals are Roofing Brief arithmetic and exclude purlins, posts, bracing, freight and labor.
The truss line is not the whole frame. A steel truss at 10 ft spacing needs purlins that span 10 ft: the SteelBarnTruss.com 30 ft truss has 22 purlin cups, which works out to 22 rows x 4 bays = 88 purlins about 10 ft long, and one maker’s engineering sheet calls for 2×6 No. 2 Southern yellow pine at that spacing. Best Buy Metals also states that its stock trusses require 6×6 structural posts. Price those items locally before deciding which frame is cheaper.
Labor tilts the comparison too. HomeGuide puts truss setting labor at $40 to $60 per truss, so 5 steel trusses involve fewer lifts than 11 or 21 wood ones, but each steel truss is heavier: Best Buy Metals lists 230 lb for its 30 ft truss and requires offload equipment on site.
How far apart should trusses be for a metal roof?
It depends on the truss and the building. Steel pole barn trusses are typically set 10 to 12 ft on center with wood purlins between them. Wood post-frame trusses are often set 2 to 8 ft apart, and house trusses are usually 24 in on center. The stamped truss drawing, not the roofing panel, sets the maximum spacing.
| Framing system | Typical truss spacing | What spans between trusses | Source |
|---|---|---|---|
| Stock steel angle-iron pole barn truss | 10 ft | 2×6 purlins in welded cups | Best Buy Metals; Armour Metals |
| Engineered steel post-frame truss | 8 to 12 ft | Wood purlins sized by the engineer | Buffalo River Truss; Lyon Metal Roofing |
| Wood truss on a farm building | Up to 4 ft | Purlins or sheathing | AW Graham Lumber 30 ft common truss listing |
| Wood truss on a house or garage | 24 in (2 ft) | Roof sheathing, then panels | AW Graham Lumber; HomeGuide |
| Cold-formed steel roof framing (IRC tables) | 16 or 24 in | Sheathing screwed to the framing | 2021 IRC Table R804.3.1.1(1) |
Purlin spacing across the trusses is a second number. Metal panel makers publish load-span tables for their panels over purlins, and the cups welded to a steel truss fix where the purlins go. Our guide to metal building framing components covers purlin types and gauges, and our purlin span table by snow load sets out how far purlins can run.
How spacing changes the snow load a steel truss can carry
Closer spacing lets the same steel truss carry more snow, because each truss supports a narrower strip of roof. One published engineering example for a 40 ft, 2 in x 2 in angle steel gable truss shows the allowable ground snow load rising from 30 psf at 12 ft spacing to 45 psf at 8 ft spacing.
| Truss spacing | Allowable ground snow load | Purlin specified | Trusses for a 40 x 60 ft barn |
|---|---|---|---|
| 12 ft | 30 psf | 2×6 No. 1 Southern yellow pine | 6 (60 / 12 = 5 bays, plus 1) |
| 10 ft | 35 psf | 2×6 No. 2 Southern yellow pine | 7 (60 / 10 = 6 bays, plus 1) |
| 8 ft | 45 psf | 2×6 No. 2 Southern yellow pine | 9 (60 / 8 = 7.5, round up to 8 bays, plus 1) |
Source: Metal Roofing Wholesalers (now Best Buy Metals Knoxville) steel truss engineering page: design per ASCE 7-10 and 7-16, ASTM A36 steel, 20 psf roof live load, 5 psf dead load, 115 mph design wind speed, Risk Category II, Exposure B. Truss counts are Roofing Brief arithmetic. These values apply to that truss only.
What load ratings do steel roof trusses carry?
A steel truss is only as good as the design loads on its stamped drawing. Best Buy Metals’ current online listing states a 20 psf roof live load, a 15 psf ground snow load at 10 ft centers and a 105 mph design wind speed rating, engineer stamped in Alabama, Tennessee, Kentucky, North Carolina and Georgia. Your county’s required snow and wind loads may be higher.
| Document | Wind | Ground snow | Roof live / dead load | Code basis stated |
|---|---|---|---|---|
| Best Buy Metals online listing (angle-iron gable truss, 10 ft centers) | 105 mph design wind speed rating (listing also cites a 90 mph wind load) | 15 psf | 20 psf live; dead 6 to 12 psf by span (product page) | IBC 2018 and 2021 |
| Metal Roofing Wholesalers engineering example (40 ft truss, 10 ft centers) | 115 mph, Risk Category II, Exposure B | 35 psf | 20 psf live / 5 psf dead | IBC 2012, 2015, 2018; ASCE 7-10 and 7-16 |
| Lyon Metal Roofing stock line | Not stated on product page | Not stated | Sold in 20 psf and 30 psf load ratings | Not stated |
Source: Best Buy Metals shop listing and steel truss product page; Metal Roofing Wholesalers engineering page; Lyon Metal Roofing product page; all checked October 18, 2026.
Risk category explains part of the gap. The 2021 IBC, Table 1604.5, puts agricultural facilities in Risk Category I, and ASCE 7 maps lower design wind speeds for Risk Category I than for Risk Category II buildings such as houses and most garages. A truss rated for a farm building may therefore need a fresh engineering review before it goes on a garage, shop or anything people occupy.
Before you order, ask the building department for the ground snow load, design wind speed and exposure category for your address, then compare them line by line with the stamped drawing for the exact truss, span and spacing. Best Buy Metals’ own note tells buyers to request stamped drawings to verify specifications for their project.
What codes apply to steel roof trusses?
Which code applies depends on the truss type and the building. Cold-formed steel trusses on houses fall under the IRC’s Section R804, which points to AISI standards. Welded angle trusses are hot-rolled structural steel and are normally engineered and stamped. Many farm buildings are handled differently from houses, so the local building department decides what it will accept.
| Provision | What it says | Applies to | Source |
|---|---|---|---|
| 2021 IRC R804.1.1 Applicability limits | Prescriptive cold-formed steel roof framing is limited to buildings not greater than 60 ft long and 40 ft wide parallel to the truss span, three stories or fewer, roof slopes 3:12 to 12:12, ultimate design wind speed under 140 mph (Exposure B or C) and ground snow load of 70 psf or less | CFS roof framing on IRC buildings | 2021 IRC (as reproduced in the 2021 Seattle Residential Code) |
| 2021 IRC R804.3.6 Roof trusses | Cold-formed steel trusses shall be designed and installed in accordance with AISI S230, Section F6; bracing per accepted practice such as the SBCA CFSBCSI guide | CFS trusses on houses | 2021 IRC |
| 2021 IRC R804.2.2 Corrosion protection | Load-bearing cold-formed steel framing shall have a protective coating complying with AISI S240, Section A4 | CFS framing | 2021 IRC |
| 2021 IRC R804.2.5 Fastening | Steel-to-steel screws are self-drilling tapping screws to ASTM C1513, at least 1/2 in edge distance and spacing | CFS connections | 2021 IRC |
| 2021 IRC R802.10 Wood trusses | Truss design drawings go to the building official before installation; metal-plate-connected wood trusses comply with ANSI/TPI 1 | Wood trusses, including those under metal roofs | 2021 IRC |
| 2021 IBC Section 2211 | Cold-formed steel light-frame construction complies with AISI S240 (the 2015 standard that absorbed the older AISI S214 truss standard) | CFS trusses on IBC buildings | 2021 IBC Chapter 22 |
| 2021 IBC Table 1604.5 | Agricultural facilities are Risk Category I (low hazard to human life) | Farm buildings designed under the IBC | 2021 IBC |
Spans beyond the IRC limits are not banned. R804.1.1.1 permits cold-formed roof framing outside those limits to be designed under AISI S230 within its own limits, and stock steel post-frame lines run to 50 or 60 ft, with special orders up to 100 ft wide (Best Buy Metals; Buffalo River Truss; Stroud’s Building Supply).
What are the downsides of steel roof trusses?
The main downsides are load ratings that may be too low for snowy regions, heavier purlins and posts at wide spacing, condensation on cold steel and panels, a painted finish that may carry no warranty, heat loss through steel in conditioned buildings, and logistics: heavy trusses, offload equipment, long custom lead times and no-return sales.
| Downside | Why it matters | What to do | Source |
|---|---|---|---|
| Low stock snow rating | One stock truss is stamped for 15 psf ground snow at 10 ft centers | Match the stamped load to your county, or tighten spacing per the engineer | Best Buy Metals listing |
| Bigger purlins and posts | 10 to 12 ft bays need 2×6 purlins and 6×6 posts | Price the whole frame, not just trusses | Best Buy Metals; Metal Roofing Wholesalers |
| Finish and corrosion | Best Buy Metals’ trusses carry no specific warranty and have a matte black finish | Touch up scratches; control barn humidity and ventilation | Best Buy Metals product page |
| Thermal bridging | The 2021 IECC sets separate rules for steel-frame ceilings because steel conducts heat | Insulate to IECC Table R402.2.6 in conditioned buildings | 2021 IECC R402.2.6 |
| Thermal movement | Steel expands about 6.5 millionths of an inch per inch per degree F: a 50 ft truss moves about 0.47 in over a 120 F swing (600 in x 120 x 0.0000065) | Detail connections for movement as the drawing shows | BuildSteel CFS truss guide; Roofing Brief arithmetic |
| Weight and handling | A 40 ft stock truss ships at 325 lb; offload equipment required | Plan a telehandler, crane or loader with spreader bar | Best Buy Metals; Lyon Metal Roofing |
| Lead time and returns | Non-stock trusses can take 6 to 8 weeks; some suppliers make all sales final | Confirm stock, lead time and return terms in writing | Stroud’s Building Supply |
Condensation is the failure barn owners notice first, because warm, moist air meets cold steel panels and framing. Our barn roofing guide covers drip-stop membranes, ventilation and the corrosion that follows long-term condensation.
How to buy and install steel pole barn trusses
Buying steel trusses is mostly a matching exercise: local loads, span, spacing and post layout have to agree with one stamped drawing. Installation is quick once that is settled, but the trusses are heavy and the hardware is specific to the maker. These steps follow the suppliers’ published instructions and the code sections above.
- Get your design loads. Ask the building department for ground snow load, design wind speed, exposure category and whether the building needs a permit or is treated as agricultural.
- Pick span, pitch and spacing. Stock trusses are usually 4/12 gables or 1/12 to 2/12 lean-tos; decide spacing from the snow load the drawing allows at each spacing.
- Request the stamped drawing. Confirm it is stamped for your state and lists your loads, span and spacing. Best Buy Metals lists stamps for AL, TN, KY, NC and GA, with many drawings also stamped for SC.
- Size posts and purlins to the drawing. One maker requires 6×6 structural posts; another specifies 2×6 No. 1 or No. 2 Southern yellow pine purlins depending on spacing.
- Order with lead time in mind. Ask about stock, freight limits and crating; Best Buy Metals notes orders over 11 trusses may need alternate shipping, and Stroud’s quotes 6 to 8 weeks for non-stock trusses.
- Plan the lift. Small lean-to trusses can be hand-set; larger spans need a telehandler, crane or loader with a boom pole and a spreader bar, per Lyon Metal Roofing.
- Set, bolt and brace. Bolt each truss to its posts with the supplied hardware, then install purlins in the welded cups and any bracing the drawing calls for before panels go on.
- Fasten the roof panels. Follow the panel maker’s screw pattern and purlin span table for the gauge you bought.
Where to buy metal roof trusses
Stock steel trusses are sold mainly by regional metal roofing and post-frame suppliers, which is why searches for metal roof trusses near me return local yards. Lines differ in spans, ratings and how the price is published, so compare the drawing, not just the sticker. The suppliers below are listed neutrally from their own pages.
| Supplier | Base | Stock spans listed | Stated rating or note |
|---|---|---|---|
| Best Buy Metals | Cleveland, TN, plus branches in TN, NC, SC, GA | Gables 20 to 50 ft; lean-to 12 and 20 ft; header 20 and 24 ft; up to 100 ft special order | 105 mph, 15 psf ground snow, 20 psf live at 10 ft |
| Stroud’s Building Supply | Morganton, NC | Gables 12 to 60 ft; lean-to 12 to 30 ft; headers 20 and 24 ft | 2 in angle steel; buyer must check local codes |
| Lyon Metal Roofing (Buffalo River Truss systems) | Piney Flats, TN | Gables 20 to 40 ft; lean-to 12 to 24 ft | 20 psf and 30 psf load ratings; 18 in overhang |
| Buffalo River Truss | Lobelville, TN | Up to 100 ft wide | Engineer-approved drawings on standard trusses; about 2 weeks for custom orders |
| Wheeler Metals | Muskogee, OK; Rogers, AR; Springfield, MO | 12 to 40 ft | Prices listed; ratings not shown on the category page |
| Quality Outdoor Products | Humboldt, TN | Gables 20 to 60 ft; shed 10 to 20 ft | Prices listed online |
Source: supplier websites, checked October 18, 2026. Our Best Buy Metals review covers that company’s branches, panels and warranty documents.
Which roof truss should you pick?
Choose steel trusses for open-span farm and storage buildings in moderate snow regions, and wood or cold-formed steel at close spacing for houses and attached garages. The table maps common situations to a starting point. In every case the stamped drawing and the local building department have the final say.
| If your project is | Start with | Why |
|---|---|---|
| A hay shed or equipment barn, 20 to 40 ft wide, low-snow county | Stock angle-iron steel gable trusses at 10 ft | Fewest trusses, posted prices, quick to set |
| A barn where the ground snow load exceeds the stock rating | Engineered steel at 8 ft spacing or a heavier custom truss | Closer spacing raised the allowable snow load from 30 to 45 psf in one published example |
| A shop wider than 40 ft with no interior posts | Engineered steel or bar-joist trusses | Stock lines run to 50 or 60 ft; special orders to 100 ft |
| A lean-to off an existing barn | Steel lean-to trusses | Stocked from 8 to 30 ft at 1/12 to 2/12 pitch |
| A wide sidewall door opening | A steel header truss or bar joist | Replaces a post; Stroud’s lists 20 and 24 ft headers at $800 and $960 |
| A house or attached garage with a finished ceiling | Wood trusses at 24 in (ANSI/TPI 1) or cold-formed steel per IRC R804 | Matches residential code paths and drywall ceilings |
| A flat or low-slope roof | Parallel chord trusses | See our flat roof trusses guide |
For wood truss pricing by type and span, see our roof truss cost guide. For what the metal panels on top will cost, see our metal roof cost guide. If the roof runs down to the floor, see our guide to A-frame roof framing and rafter spans.
Frequently asked questions
Are metal trusses cheaper than wood?
Per truss, usually not: HomeGuide (January 2026) lists wood trusses at $60 to $500 and steel at $150 to $700+. Per building, steel can match or beat wood on a pole barn because it is spaced 10 ft apart. For a 30 x 40 ft barn, 5 steel trusses cost about $1,650 to $3,100 versus $1,320 to $3,630 for 11 wood trusses at 4 ft, before purlins and posts.
How much is a 30 ft metal truss?
A stock 30 ft steel gable truss at a 4/12 pitch listed at $330 to $620 at five US suppliers on October 18, 2026: Wheeler Metals $330, SteelBarnTruss.com $360.64, Best Buy Metals $452, Stroud’s Building Supply $577.50 and Quality Outdoor Products $620. Freight, tax and hardware terms vary, and the load ratings differ, so compare stamped drawings before price.
What are the downsides of steel roof trusses?
Stock steel trusses may carry low snow ratings, such as 15 psf ground snow at 10 ft centers on one listing. Wide spacing needs 2×6 purlins and 6×6 posts, steel panels and framing can drip condensation, finishes may carry no warranty, and steel conducts heat in insulated buildings. Large trusses also need lifting equipment and can take 6 to 8 weeks to order.
How far apart should trusses be for a metal roof?
Steel pole barn trusses are typically 10 to 12 ft apart, with an 8 to 12 ft range by design. Wood trusses on farm buildings run up to 4 ft apart, and wood trusses on houses are usually 24 in on center under sheathing. The stamped truss drawing sets the maximum spacing for your snow and wind loads, and closer spacing raises the snow load a truss can carry.
How many steel trusses do I need for a 30 x 40 pole barn?
At 10 ft spacing, a 30 x 40 ft pole barn needs 5 steel trusses: 40 ft divided by 10 ft gives 4 bays, and you add 1 truss to close the last bay. At 8 ft spacing it needs 6 trusses. Gable-end details, overhangs or extra openings can change the count, so confirm it against the building plan and the truss drawing.
How much is a 40 ft metal truss?
A stock 40 ft steel gable truss listed at $430 to $770 on October 18, 2026: Wheeler Metals $430, Best Buy Metals $568, SteelBarnTruss.com $600, Quality Outdoor Products $630 and Stroud’s Building Supply $770. A custom 6/12 pitch raised the 40 ft price at Stroud’s to $910. Best Buy Metals lists a 325 lb shipping weight for its 40 ft truss.
How much does a 20 foot metal truss cost?
A stock 20 ft steel gable truss listed at $219 to $420 on October 18, 2026, with Wheeler Metals at $219, SteelBarnTruss.com at $306.64, Best Buy Metals at $342, Stroud’s Building Supply at $385 and Quality Outdoor Products at $420. For comparison, HomeGuide lists a 20 ft wood truss at $90 to $250 for material only, with installation extra.
Sources
- Supplier price pages and stores, checked October 18, 2026: Best Buy Metals (shop.bestbuymetals.com steel gable trusses; bestbuymetalroofing.com steel trusses), Stroud’s Building Supply (steel trusses, custom trusses, 30 ft gable), SteelBarnTruss.com prices, Wheeler Metals trusses, Quality Outdoor Products pole barn trusses, Lyon Metal Roofing steel trusses, Buffalo River Truss.
- Armour Metals truss pricing page (prices marked effective September 21, 2021).
- Metal Roofing Wholesalers (Best Buy Metals Knoxville), Steel Truss Engineering page.
- HomeGuide, How Much Do Roof Trusses Cost? (January 21, 2026).
- AW Graham Lumber, 30 ft span 4/12 pitch common roof truss listing.
- International Code Council, 2021 International Residential Code, Sections R802.10 and R804, as reproduced in the 2021 Seattle Residential Code, Chapter 8.
- International Code Council, 2021 International Building Code, Table 1604.5 and Section 2211; 2021 International Energy Conservation Code, Section R402.2.6.
- BuildSteel.org (Steel Framing Industry Association program), Cold-Formed Steel Trusses: Design, Performance, and Advantages.