Strut Channel Sizes & Load Chart
Every 1-5/8 in. series channel is the same 1-5/8 in. (41.3 mm) wide, with the same 7/8 in. (22.2 mm) open face, so they all take the same fittings and nuts. What separates the eighteen series is depth and steel gauge — which set how much load the run carries and how far it spans.
This page compares strut channel dimensions for all eighteen 1-5/8 in. series side by side: profile, gauge, steel thickness, allowable moment, the P1000 span table and the hole pattern codes.
Straight to the numbers: full specification table
Working in millimetres? 41x41 and 41x21 explained · Choosing a coating? all the finishes, with the ASTM number behind each
Go straight to the series tables and read the row. The search box in the header takes a part number on any page.
B-Line, Superstrut, Power-Strut or Haydon. The cross-reference table prints what each published document lists opposite it, with the source named on every cell.
Depth buys span, gauge buys corrosion margin, back-to-back is the last move. The order to work in is set out here.
How the series are named
The numbering looks arbitrary until you see the two rules behind it. First, a trailing 01 means back-to-back: two channels welded lip to lip, so P1000 becomes P1001, P1100 becomes P1101, P3300 becomes P3301, and so on through the range. Second, a different leading number at the same profile means a different gauge. P1000, P1100 and P2000 are all 1-5/8 x 1-5/8 in. and look identical in the rack; they are 12, 14 and 16 gauge steel respectively.
That second rule is the one that catches people out. Two lengths of channel can be dimensionally interchangeable, accept the same channel nuts and the same fittings, and still differ by 30 percent in what they will carry. If a drawing calls for P1000 and the yard sends P2000, nothing will look wrong at assembly.
Choosing depth and gauge
Work in this order. Depth first: it is what actually buys span. Going from 1-5/8 in. deep (P1000) to 3-1/4 in. deep (P5000) roughly triples the allowable moment at the same 12 gauge steel. Adding gauge cannot do that — dropping from 16 to 12 gauge at a fixed profile buys about 44 percent.
Then back-to-back, if depth alone is not enough. Welding two channels lip to lip multiplies the allowable moment by between 2.1 and 3.0 depending on the pair — it is not the clean doubling people assume, and the ratio is worst on the deepest section (P5000 to P5001 gains only 2.15x). Back-to-back also doubles the weight and the price, so it is the last move, not the first.
Gauge last, and mostly for corrosion and handling rather than strength. Thinner channel dents in transit, strips more easily when a nut is over-torqued, and gives the zinc less steel to protect.
Finishes
Four catalog finishes cover the channel range: PL plain, PG pre-galvanized (ASTM A653 G90), HG hot-dip galvanized after fabrication (ASTM A123), and GR Perma-Green II paint. The choice that matters is not the channel’s finish on its own but the pairing. Match the fitting finish to the channel: a thinner zinc coating (EG) or bare steel (PL) will show rust well before hot-dip galvanized channel does, so a mixed run is only as durable as its least protected part — the bolt and the channel nut included.
Full specification table
Single channel — 9 series
| Series | Profile in. (mm) | Gauge | Steel in. (mm) | Allow. moment in-lbs |
|---|---|---|---|---|
| P1000 | 1-5/8 x 1-5/8 (41.3 x 41.3) | 12 ga | 0.105 (2.7) | 5,080 |
| P1100 | 1-5/8 x 1-5/8 (41.3 x 41.3) | 14 ga | 0.075 (1.9) | 4,170 |
| P2000 | 1-5/8 x 1-5/8 (41.3 x 41.3) | 16 ga | 0.060 (1.5) | 3,520 |
| P3000 | 1-5/8 x 1-3/8 (41.3 x 34.9) | 12 ga | 0.105 (2.7) | 3,870 |
| P3300 | 1-5/8 x 7/8 (41.3 x 22.2) | 12 ga | 0.105 (2.7) | 1,810 |
| P4000 | 1-5/8 x 13/16 (41.3 x 20.6) | 16 ga | 0.060 (1.5) | 1,210 |
| P4100 | 1-5/8 x 13/16 (41.3 x 20.6) | 14 ga | 0.075 (1.9) | 1,330 |
| P5000 | 1-5/8 x 3-1/4 (41.3 x 82.6) | 12 ga | 0.105 (2.7) | 15,790 |
| P5500 | 1-5/8 x 2-7/16 (41.3 x 61.9) | 12 ga | 0.105 (2.7) | 9,830 |
Width is 1-5/8 in. (41.3 mm) across every series. Allowable moment is the catalog figure for the reference part and is not a rating for parts we supply; see Made to order below. P2000: p. 36 prints 3,520 in-lbs (570 N·m), and 570 N·m is P1000’s figure, not a conversion of 3,520 in-lbs; the p. 24 strength table prints 3,521 in-lbs (398 N·m) for the same section, so if you need P2000 in metric, p. 24 is the page to read. P4100 and its back-to-back P4101 are on p. 50; the p. 24 strength table prints them as 1,333 and 3,546 in-lbs, and the table shows the p. 50 figures. Source: Unistrut® General Engineering Catalog no. 17, p. 24, 25–56 · Verified 2026-09-27
Back-to-back channel — 9 series
Show the table — 9 rows
| Series | Profile in. (mm) | Gauge | Steel in. (mm) | Allow. moment in-lbs |
|---|---|---|---|---|
| P1001 | 1-5/8 x 3-1/4 (41.3 x 82.6) | 12 ga | 0.105 (2.7) | 14,390 |
| P1101 | 1-5/8 x 3-1/4 (41.3 x 82.6) | 14 ga | 0.075 (1.9) | 11,470 |
| P2001 | 1-5/8 x 3-1/4 (41.3 x 82.6) | 16 ga | 0.060 (1.5) | 9,530 |
| P3001 | 1-5/8 x 2-3/4 (41.3 x 69.9) | 12 ga | 0.105 (2.7) | 10,840 |
| P3301 | 1-5/8 x 1-3/4 (41.3 x 44.5) | 12 ga | 0.105 (2.7) | 5,080 |
| P4001 | 1-5/8 x 1-5/8 (41.3 x 41.3) | 16 ga | 0.060 (1.5) | 3,140 |
| P4101 | 1-5/8 x 1-5/8 (41.3 x 41.3) | 14 ga | 0.075 (1.9) | 3,550 |
| P5001 | 1-5/8 x 6-1/2 (41.3 x 165.1) | 12 ga | 0.105 (2.7) | 33,910 |
| P5501 | 1-5/8 x 4-7/8 (41.3 x 123.8) | 12 ga | 0.105 (2.7) | 29,000 |
Each is the welded pair of the single series one number below. Allowable moment is the catalog figure for the reference part and is not a rating for parts we supply; see Made to order below. Source: Unistrut® General Engineering Catalog no. 17, p. 25–56 · Verified 2026-09-27
P1000 span vs. load
Allowable moment is a property of the section; what you actually want to know is what a given run will hold. This is the standard 12-gauge P1000 as a simple beam, uniformly loaded. The last three columns are the load at which deflection reaches span/180, span/240 and span/360 — the usual serviceability limits for pipe runs, cable tray and finished ceilings respectively.
Show the table — 14 rows
| Span in. | Allow. load lbs | Max defl. in. | @ L/180 | @ L/240 | @ L/360 |
|---|---|---|---|---|---|
| 24 | 1,690 | 0.06 | 1,690 | 1,690 | 1,690 |
| 36 | 1,130 | 0.13 | 1,130 | 1,130 | 900 |
| 48 | 850 | 0.22 | 850 | 760 | 510 |
| 60 | 680 | 0.35 | 650 | 490 | 320 |
| 72 | 560 | 0.5 | 450 | 340 | 220 |
| 84 | 480 | 0.68 | 330 | 250 | 170 |
| 96 | 420 | 0.89 | 250 | 190 | 130 |
| 108 | 380 | 1.13 | 200 | 150 | 100 |
| 120 | 340 | 1.4 | 160 | 120 | 80 |
| 144 | 280 | 2.01 | 110 | 80 | 60 |
| 168 | 240 | 2.74 | 80 | 60 | 40 |
| 192 | 210 | 3.57 | 60 | 50 | NR |
| 216 | 190 | 4.52 | 50 | 40 | NR |
| 240 | 170 | 5.58 | 40 | NR | NR |
Catalog rating for the reference part, not for parts we supply.
NR = not recommended. Beyond about 8 ft the governing limit is deflection, not strength — note how the L/360 column collapses while the strength column barely moves. Source: Unistrut® General Engineering Catalog no. 17, p. 26 · Verified 2026-07-14
Hole patterns
The suffix after the series number is the hole pattern, and it changes where you can land a bolt — not whether a fitting fits. Any fitting bolts through any pattern.
Show the table — 6 rows
| Code | Hole | Spacing / notes | Offered on |
|---|---|---|---|
| HS | 9/16 in. (14.3) round holes | 1-7/8 in. (47.6) on center | all nine single series |
| T | 1-1/8 x 9/16 in. (28.6 x 14.3) slots | 2 in. (51) on center | all nine single series |
| SL | 3 x 13/32 in. (76.2 x 10.3) slots | 4 in. (101.6) on center | all nine single series |
| KO | 7/8 in. (22.2) knockouts | 6 in. (152.4) on center | all but P3300, P4000 and P4100 |
| DS | 2-3/4 x 7/8 in. (69.9 x 22.2) slots | 3-1/2 in. (88.9) on center; pipe clamps can mount on both sides | P1000 only |
| H3 | 9/16 in. (14.3) round holes | 1-7/8 in. (47.6) on center; same printed size and spacing as HS, and the catalog does not say in words how the two differ | P1000 only |
Sizes and spacing: Unistrut® General Engineering Catalog no. 17, p. 25. Which series each code is offered on: the Hole Pattern Styles columns of the p. 24 Channel Selection Chart · Verified 2026-09-27
Where it is used
- Pipe trapeze
- Page 157 selects from P3000, P1000, P5500 and P5000 for single-channel sprinkler trapezes and from P3001, P1001, P5501 and P5001 for double-channel ones, by span and pipe diameter against the NFPA 13 section-modulus table; p. 156 does the same for Schedule 10 pipe.
- Electrical runs
- Page 161 puts channel under raceways, trapeze hangers, cable-tray supports, lighting grids and fluorescent-fixture supports, in continuous lengths of up to 20 feet.
- Seismic bracing
- Page 84 draws P1000 as a lateral brace and as a transverse brace with the P2485 cradle clip, and refers the detail to a separate bracing catalog.
- General framing
- Page 9 calls the 1-5/8 in. series the accepted standard for mechanical, electrical and general construction supports.
Source: Unistrut® General Engineering Catalog no. 17, p. 9, 84, 156–157, 161 · Verified 2026-09-19
Made to order
Nothing here ships from a shelf. What we quote against a series number is a candidate substitute made to order by a contract manufacturer, not an original-manufacturer part.
- Finishes
- Plain, EG, HDG and stainless, plus powder coating on request.
- Minimum order
- Minimum order: none. Most orders are a few hundred pieces; smaller runs are quoted too.
- Lead time
- Production lead time: 5–7 business days, ex-factory. Counted from order confirmation and receipt of deposit (or drawing approval for custom parts, whichever is later). This does not include transit.
- Catalog vs. ours
- Gauge and steel thickness in the table above are catalog figures for the reference series. The thickness and steel grade we supply are quoted on their own line and never merged into that column.
Before you order
- Length before quantity. Channel is priced by the length; a piece count with no length cannot be quoted.
- Series and hole pattern together. P1000T and P1000HS are the same steel with different holes — the suffix is part of the callout.
- Name the finish. Finishes differ in price, and a fitting finish that does not match the channel corrodes first.
- Destination, Incoterm and port. Transit is quoted separately by method and destination; the Incoterm and port are stated on each quote.
- Say if you need submittal documents. What we can and cannot supply is settled in the quote, not after the PO.
Frequently asked questions
Do all 1-5/8 in. channel series take the same fittings?
Yes. Every series in this table is 1-5/8 in. (41.3 mm) wide with the same inturned lips, so channel nuts and fittings interchange across P1000, P1100, P2000, P3000 and the rest. What changes between series is depth and steel gauge, which set how much load the channel carries, not what bolts to it.
What is the difference between P1000, P1100 and P2000?
Nothing visible from the open face: all three are 1-5/8 x 1-5/8 in. The difference is steel thickness, 12 gauge (0.105 in.), 14 gauge (0.075 in.) and 16 gauge (0.060 in.). Published load data belongs to the reference part; see the catalog p. 24.
What does the 01 suffix mean, as in P1001?
It is the back-to-back version of the same profile, two channels welded lip to lip. P1000 becomes P1001, P1100 becomes P1101, and so on. Back-to-back does not double the strength: across every pair in the table the allowable moment multiplies by between 2.1 and 3.0 depending on the pair, not by 2.
Which hole pattern should I order?
HS is the 9/16 in. round hole at 1-7/8 in. centers, for a bolt straight through the back. T is a narrower slot (1-1/8 x 9/16 in.) on 2 in. centers, and SL is a wider slot (3 x 13/32 in.) on 4 in. centers; both give lateral adjustment after the run is up. KO knockouts suit electrical boxes; the catalog does not list P3300, P4000 or P4100 for KO. DS and H3 are P1000 only. Fittings bolt through any of them; the pattern changes where you can land a bolt, not whether it fits.
What 12-gauge and 14-gauge strut channel options come in 10-foot and 20-foot lengths?
Twelve gauge covers P1000, P3000, P3300, P5000 and P5500, plus their back-to-back pairs; 14 gauge is P1100, P1101, P4100 and P4101. On length the catalog says only that channel is available in continuous lengths of up to 20 feet (p. 161), so both 10 ft and 20 ft sit inside that. The length we can supply against a given series is confirmed at quotation and is not published here.
Get these part numbers quoted
We source strut channel from the mills that produce it. Tell us the part number, the finish, the quantity and the destination, and we come back with our part number, finish options, lead time and packing quantity. There is no list price — it is quoted per mill, finish and volume.
No minimum order · 5–7 business days ex-factory · Reply within one business day (Asia/Shanghai, UTC+8) · Finishes: plain, EG, HDG, stainless
Prefer email? Write to contact@channelstrut.com. Minimum order quantity, production lead time, transit and samples are set out in full under Ordering terms.