HDPE (PE 100) Square Tube Weight
Mass per metre and per foot for hdpe (pe 100) square tube at 960 kg/m³ (ISO 4427 / ASTM D3350 (PE 100 black)). Every figure is for the section as drawn. A 6 m length of this size weighs 2.6 kg (5.7 lb per 20 ft).
At the reference dimensions (a = 40 mm, t = 3 mm) this section has a cross-sectional area of 444.0 mm², giving 0.426 kg/m (0.286 lb/ft). Against carbon steel's 7,850 kg/m³ that is -87.8 % — the same section in steel would be 3.485 kg/m.
Square Tube — formula and derivation
Area of a square tube
A = a² − (a − 2t)²
A = a² − (a − 2t)², which expands to A = 4t(a − t)
Worked through with the default dimensions:
A = a² − (a − 2t)²Inner side = 40 − 2 × 3 = 34.0 mmA = 40² − 34.0²A = 1600.0 − 1156.0A = 444.0 mm²
- a
- Side
- t
- Wall thickness
Weight follows from the area with no further geometry: m = A × 10⁻⁶ × ρ, where A is in mm², ρ in kg/m³ and m in kg/m. At 960 kg/m³ that is 0.4262 kg/m for the reference size above.
HDPE square tube — size series
| Side | 1.5 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|
| 15 mm | 0.078 kg/m · 0.052 lb/ft | 0.100 kg/m · 0.067 lb/ft | 0.138 kg/m · 0.093 lb/ft | 0.169 kg/m · 0.114 lb/ft | 0.192 kg/m · 0.129 lb/ft | 0.207 kg/m · 0.139 lb/ft |
| 20 mm | 0.107 kg/m · 0.072 lb/ft | 0.138 kg/m · 0.093 lb/ft | 0.196 kg/m · 0.132 lb/ft | 0.246 kg/m · 0.165 lb/ft | 0.288 kg/m · 0.194 lb/ft | 0.323 kg/m · 0.217 lb/ft |
| 25 mm | 0.135 kg/m · 0.091 lb/ft | 0.177 kg/m · 0.119 lb/ft | 0.253 kg/m · 0.170 lb/ft | 0.323 kg/m · 0.217 lb/ft | 0.384 kg/m · 0.258 lb/ft | 0.438 kg/m · 0.294 lb/ft |
| 30 mm | 0.164 kg/m · 0.110 lb/ft | 0.215 kg/m · 0.145 lb/ft | 0.311 kg/m · 0.209 lb/ft | 0.399 kg/m · 0.268 lb/ft | 0.480 kg/m · 0.323 lb/ft | 0.553 kg/m · 0.372 lb/ft |
| 40 mm | 0.222 kg/m · 0.149 lb/ft | 0.292 kg/m · 0.196 lb/ft | 0.426 kg/m · 0.286 lb/ft | 0.553 kg/m · 0.372 lb/ft | 0.672 kg/m · 0.452 lb/ft | 0.783 kg/m · 0.526 lb/ft |
| 50 mm | 0.279 kg/m · 0.188 lb/ft | 0.369 kg/m · 0.248 lb/ft | 0.541 kg/m · 0.364 lb/ft | 0.707 kg/m · 0.475 lb/ft | 0.864 kg/m · 0.581 lb/ft | 1.014 kg/m · 0.681 lb/ft |
| 60 mm | 0.337 kg/m · 0.226 lb/ft | 0.445 kg/m · 0.299 lb/ft | 0.657 kg/m · 0.441 lb/ft | 0.860 kg/m · 0.578 lb/ft | 1.056 kg/m · 0.710 lb/ft | 1.244 kg/m · 0.836 lb/ft |
| 80 mm | 0.452 kg/m · 0.304 lb/ft | 0.599 kg/m · 0.403 lb/ft | 0.887 kg/m · 0.596 lb/ft | 1.167 kg/m · 0.784 lb/ft | 1.440 kg/m · 0.968 lb/ft | 1.705 kg/m · 1.146 lb/ft |
| 100 mm | 0.567 kg/m · 0.381 lb/ft | 0.753 kg/m · 0.506 lb/ft | 1.117 kg/m · 0.751 lb/ft | 1.475 kg/m · 0.991 lb/ft | 1.824 kg/m · 1.226 lb/ft | 2.166 kg/m · 1.455 lb/ft |
Rows: side (mm). Columns: wall thickness (mm). Computed for HDPE (PE 100) at 960 kg/m³.
| Side | 1.5 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|
| 15 mm | 81.0 | 104.0 | 144.0 | 176.0 | 200.0 | 216.0 |
| 20 mm | 111.0 | 144.0 | 204.0 | 256.0 | 300.0 | 336.0 |
| 25 mm | 141.0 | 184.0 | 264.0 | 336.0 | 400.0 | 456.0 |
| 30 mm | 171.0 | 224.0 | 324.0 | 416.0 | 500.0 | 576.0 |
| 40 mm | 231.0 | 304.0 | 444.0 | 576.0 | 700.0 | 816.0 |
| 50 mm | 291.0 | 384.0 | 564.0 | 736.0 | 900.0 | 1,056.0 |
| 60 mm | 351.0 | 464.0 | 684.0 | 896.0 | 1,100.0 | 1,296.0 |
| 80 mm | 471.0 | 624.0 | 924.0 | 1,216.0 | 1,500.0 | 1,776.0 |
| 100 mm | 591.0 | 784.0 | 1,164.0 | 1,536.0 | 1,900.0 | 2,256.0 |
Area is a property of the geometry alone, so this table is the same for every material. It is what you enter into a stress calculation; the mass table is what you enter into an order.
Each row is one nominal size. Because the area is computed from your dimensions rather than read from a mill table, a non-standard size is just as accurate — put it into the calculator above rather than interpolating between rows.
The same square tube in every material
Geometry is fixed and only density changes, so this table is the whole material-selection question in one view. HDPE (PE 100) is highlighted. The percentage column is against carbon steel, which is the figure most quotations are built on.
| Material | Density kg/m³ | lb/in³ | Mass / length kg/m | lb/ft | vs carbon steel |
|---|---|---|---|---|---|
| Carbon Steel | 7,850 | 0.2836 | 3.485 | 2.342 | +0.0 % |
| Stainless Steel 304 | 8,000 | 0.2890 | 3.552 | 2.387 | +1.9 % |
| Stainless Steel 316 | 8,000 | 0.2890 | 3.552 | 2.387 | +1.9 % |
| Stainless Steel 316L | 8,000 | 0.2890 | 3.552 | 2.387 | +1.9 % |
| Stainless Steel 430 | 7,700 | 0.2782 | 3.419 | 2.297 | -1.9 % |
| Aluminum 6061-T6 | 2,700 | 0.0975 | 1.199 | 0.806 | -65.6 % |
| Aluminum 5052-H32 | 2,680 | 0.0968 | 1.190 | 0.800 | -65.9 % |
| Aluminum 7075-T6 | 2,810 | 0.1015 | 1.248 | 0.838 | -64.2 % |
| Copper C11000 | 8,940 | 0.3230 | 3.969 | 2.667 | +13.9 % |
| Brass C36000 | 8,500 | 0.3071 | 3.774 | 2.536 | +8.3 % |
| Bronze C93200 | 8,800 | 0.3179 | 3.907 | 2.626 | +12.1 % |
| Titanium Grade 2 | 4,510 | 0.1629 | 2.002 | 1.346 | -42.5 % |
| Gray Cast Iron | 7,200 | 0.2601 | 3.197 | 2.148 | -8.3 % |
| Lead | 11,340 | 0.4097 | 5.035 | 3.383 | +44.5 % |
| Rigid PVC (Type I) | 1,400 | 0.0506 | 0.622 | 0.418 | -82.2 % |
| HDPE (PE 100) | 960 | 0.0347 | 0.426 | 0.286 | -87.8 % |
Same geometry throughout, so the only variable is density. Carbon steel is highlighted as the baseline.
A note on using this table for costing: mass is not price. Aluminium is roughly a third of steel's mass here, but per kilogram it costs several times more, so a straight swap rarely saves money — what it buys is reduced load on a structure or a vehicle.
About hdpe (pe 100)
High-density polyethylene and the lightest material in the catalogue at 960 kg/m³ — it floats. That is not a curiosity: buoyancy governs how submerged outfall and intake lines are installed, and HDPE’s ability to be towed and floated into place in long strings is why it displaced steel for marine pipelines. It is also tougher than PVC at low temperature and tolerates ground movement without cracking, at the cost of much lower pressure rating at the same wall thickness.
- Density
- 960 kg/m³ = 0.0347 lb/in³ · 0.1223× carbon steel · typical spread ±2 %
- Specification
- ISO 4427 / ASTM D3350 (PE 100 black)
- Equivalents
- EN PE 100 · JIS PE100 · GB PE100
- Typical uses
- Water and gas mains · Submarine outfall lines · Landfill and leachate pipe · Geomembrane and lining
Density splits into two families: PE 100 pipe grades 950–960 kg/m³, PE 63/80 grades 930–945 kg/m³. Black compound includes ~2 % carbon black.
About square tube
Square tube expands cleanly to A = 4t(a − t), which makes the sensitivity obvious: for a given side, weight is almost exactly linear in wall thickness. Doubling a 2 mm wall to 4 mm adds about 1.9 times the mass, not twice, because the inner void shrinks as the wall grows. Its flat faces also make it the natural choice for welded frames and for anything that has to be drilled, tapped or bolted through a face — a round tube gives you only a tangent point where a square tube gives you a full flat.
Specified as side × wall thickness. Corner radii are standardised per EN 10219 and change the area slightly at heavier walls.
Download this data
HDPE square tube — CSV
Both buttons below read the tables rendered on this page, so the file matches what you are looking at. The full catalogue — all 16 materials across all 10 sections — is on the downloads page.
Fields are quoted per RFC 4180, with a UTF-8 byte-order mark so Excel reads the mm² and · characters correctly. Blank lines separate the weight matrix from the area matrix.
Frequently asked questions
How much does hdpe (pe 100) square tube weigh?
At the reference dimensions (a = 40 mm, t = 3 mm) a hdpe (pe 100) square tube of this size weighs 0.426 kg/m, or 0.286 lb/ft. The table above lists the figure for every standard size so you can read your size directly instead of scaling.
How is the weight of square tube calculated?
Weight is cross-sectional area × length × density. For this shape the area is A = a² − (a − 2t)². At the reference dimensions that gives 444.0 mm², and multiplying by hdpe (pe 100)'s density of 960 kg/m³ gives 0.426 kg/m. Nothing is looked up in a table — which is why a non-standard size is calculated just as accurately as a standard one.
Why does hdpe (pe 100) weigh more or less than steel?
It is lighter than carbon steel for the same section — about 88 % lighter at 960 kg/m³. Density is the only variable: the cross-sectional area depends purely on geometry, so a square tube of the same dimensions has the same area in every material and the mass simply scales with density. In this case the ratio is 0.1223× carbon steel.
What is the cross-sectional area of a square tube?
The area depends only on the dimensions, not on the material, so it is identical whichever material you select: at the reference dimensions it is 444.0 mm² (0.6882 in²). That is the number you would enter into a stress or deflection calculation, and it is why changing material on this page never changes the area column.
Does a hdpe square tube weigh the same as a hdpe part of a different shape?
No, and the difference is larger than most people expect. At equal nominal size, a square bar is 27.3 % heavier than a round bar, and a hollow section is typically 60–80 % lighter than the solid bar it replaces. Weight follows area, and area changes faster than dimensions do — which is exactly why this needs calculating rather than estimating.
Should I use HDPE weight or carbon steel weight for costing?
Use the material you are actually buying. At 960 kg/m³ against carbon steel's 7,850 kg/m³, the same square tube differs by 87.8 % in mass. On a per-metre quote that is invisible; on a fabricated tonnage it is the difference between a margin and a loss. This page computes the steel figure as 3.485 kg/m for comparison.
Other materials, same square tube
The same geometry in every material, so the only variable is density.
- Carbon steel square tube — 7850 kg/m³
- SS 304 square tube — 8000 kg/m³
- SS 316 square tube — 8000 kg/m³
- AL 6061 square tube — 2700 kg/m³
- Copper square tube — 8940 kg/m³
- Brass square tube — 8500 kg/m³
- PVC square tube — 1400 kg/m³
- AL 5052 square tube — 2680 kg/m³
Other HDPE sections
The same density applied to every shape the site covers.
- HDPE round bar — A = π/4 · d²
- HDPE square bar — A = a²
- HDPE hexagonal bar — A = (√3/2) · AF² ≈ 0.8660 · AF²
- HDPE flat bar — A = w · t
- HDPE plate — A = w · t
- HDPE round tube — A = π/4 · (D² − d²), d = D − 2t
Reference data and tools
- Metal weight overview — how the calculation works
- All 16 materials — densities and specifications
- All 10 sections — formulas and size series
- Density chart — lightest to heaviest
- Metal weight calculator — any size, any material
- All calculators — metal weight and pipe weight
- Download the data — CSV, generated from the same source
- Cross-reference tables — DN / NPS / material equivalents
- Methodology and sources — where every number comes from
Square Tube area from A = a² − (a − 2t)². Mass computed as area × length × density at 960 kg/m³ (ISO 4427 / ASTM D3350 (PE 100 black)). No weight on this page is copied from a published table — which is why figures can differ in the last significant digit from a mill's chart calculated at a nominal density.
- Elementary plane geometry. The circle, polygon and hollow-section area formulas.
- ASTM material specifications for each grade named in the material entry (A36, A240/A276, B209/B211/B221, B152/B16/B505, B265/B348, A48, B29, D1784, D3350).
- BIPM / NIST definitional constants: international inch = 25.4 mm, foot = 0.3048 m, pound = 0.45359237 kg.
Dataset version 2026.09.1 · dimensions last verified against source 2026-09-21. Found an error? Report it — corrections are issued with a version bump.