The size of a sectional water tank is set by its panel module: GRP panels measure 1,000 × 1,000 mm, while stainless and galvanized steel panels measure 1,080 × 1,080 mm. One cubic metre holds 1,000 litres, so a 10 m³ (10,000-litre) tank is 216 × 216 × 216 cm in steel or, for example, 2 × 2 × 2.5 m in GRP. When sizing the room, allow at least 50 cm to walls, columns and the ceiling.
Contents
- Panel sizes and height steps
- Steel sectional tank size chart (1.26–90 m³)
- GRP panel tank dimensions: 5 to 100 m³
- How much space does a 10 m³ tank need?
- Large tanks: 100 m³ and above
- Clearances, access and the concrete base
- Standard connection sizes by capacity
- What we need to size your tank
- Frequently Asked Questions
Panel sizes and height steps
A sectional (panel) tank is built from standard panels bolted together on site, so its width and length follow the panel module and its height grows in whole or half panel steps. These are the panel sizes and height steps given in our Aquatank Product Catalogue 2026 (pp. 4, 8, 11, 16):
| Specification | GRP panel tank | Stainless and galvanized steel tank |
|---|---|---|
| Panel size | 1,000 × 1,000 mm | 1,080 × 1,080 mm |
| Height range | 1.0–5.0 m | 540–4,320 mm |
| Height step | 0.5 m (half wall panel 1,000 × 500 mm) | 540 mm |
| Standard capacity | No fixed range; sized per project | 1.26–90 m³ |
Volume is simply width × length × height. A 3 × 2 × 2 m GRP tank has a gross volume of 12 m³, or 12,000 litres. Not sure how much storage you need? Start with our water tank sizing guide.
Steel sectional tank size chart (1.26–90 m³)
Stainless steel (AISI 304 / 316 L) and hot-dip galvanized (ST 37) tanks use the same pressed 1,080 × 1,080 mm panel, with a standard capacity range of 1.26–90 m³ (pp. 15–16). The sizes below are selected from the layouts shown in the catalogue. The last column is the gross volume calculated from those dimensions; the catalogue capacity is its rounded nominal figure.
| Capacity (catalogue) | Size, cm (W × L × H) | Panels (W × L × H) | Gross volume (calculated) |
|---|---|---|---|
| 1.26 m³ | 108 × 108 × 108 | 1 × 1 × 1 | 1.26 m³ |
| 2.50 m³ | 108 × 216 × 108 | 1 × 2 × 1 | 2.52 m³ |
| 2.50 m³ | 108 × 108 × 216 | 1 × 1 × 2 | 2.52 m³ |
| 5.00 m³ | 216 × 216 × 108 | 2 × 2 × 1 | 5.04 m³ |
| 5.00 m³ | 216 × 108 × 216 | 2 × 1 × 2 | 5.04 m³ |
| 7.50 m³ | 324 × 108 × 216 | 3 × 1 × 2 | 7.56 m³ |
| 10.00 m³ | 216 × 216 × 216 | 2 × 2 × 2 | 10.08 m³ |
| 15.00 m³ | 324 × 216 × 216 | 3 × 2 × 2 | 15.12 m³ |
| 20.00 m³ | 432 × 216 × 216 | 4 × 2 × 2 | 20.16 m³ |
| 22.50 m³ | 324 × 324 × 216 | 3 × 3 × 2 | 22.67 m³ |
| 25.00 m³ | 540 × 216 × 216 | 5 × 2 × 2 | 25.19 m³ |
| 30.00 m³ | 324 × 432 × 216 | 3 × 4 × 2 | 30.23 m³ |
| 40.00 m³ | 432 × 432 × 216 | 4 × 4 × 2 | 40.31 m³ |
| 50.00 m³ | 540 × 432 × 216 | 5 × 4 × 2 | 50.39 m³ |
| 90.00 m³ | 648 × 432 × 324 | 6 × 4 × 3 | 90.70 m³ |
One capacity can take several shapes: a 5 m³ tank can be 216 × 216 × 108 cm for a low plant room or 216 × 108 × 216 cm for a narrow one. Intermediate sizes and special capacities are made to order (p. 15).
The chart applies to both the stainless steel tank and the galvanized tank. Among steel tanks, choose stainless steel for drinking water. The TSEK certificate shown in the catalogue classes the galvanized tank as "not intended for drinking or domestic-use water" (p. 21), so galvanized steel suits uses such as fire water and process water. Our GRP vs stainless vs galvanized comparison explains the differences.
GRP panel tank dimensions: 5 to 100 m³
The catalogue gives no fixed capacity chart for the GRP water tank; each tank is sized per project. Width and length follow the 1,000 mm panel module, and height is chosen from 1.0 to 5.0 m in 0.5 m steps (catalogue pp. 5, 8, 11). The catalogue's partitioned-tank example also shows 2 × 1.5 × 2 m tanks (p. 13), so half-metre plan dimensions may be possible; confirm the exact footprint for your project with us. We calculated the examples below with whole-metre plan dimensions: width × length × height gives the capacity.
| Capacity | Size (W × L × H) and check | Best for |
|---|---|---|
| 5 m³ | 2 × 1 × 2.5 m = 5 m³ | Small footprint, good headroom |
| 5 m³ | 5 × 1 × 1 m = 5 m³ | Low headroom, long narrow space |
| 10 m³ | 2 × 2 × 2.5 m = 10 m³ | Compact layout |
| 10 m³ | 5 × 2 × 1 m = 10 m³ | Low headroom |
| 20 m³ | 4 × 2 × 2.5 m = 20 m³ | Compact layout |
| 20 m³ | 5 × 2 × 2 m = 20 m³ | Medium headroom |
| 50 m³ | 5 × 4 × 2.5 m = 50 m³ | Compact layout |
| 50 m³ | 5 × 5 × 2 m = 50 m³ | Square footprint, medium height |
| 100 m³ | 8 × 5 × 2.5 m = 100 m³ | Large footprint |
| 100 m³ | 10 × 5 × 2 m = 100 m³ | Wide, low space |
| 100 m³ | 5 × 5 × 4 m = 100 m³ | High-ceiling plant room |
These sizes are examples and show nominal gross volume. Usable water volume is somewhat lower because of the air space above the overflow, and the external footprint grows slightly with corner profiles, external bracing, the steel skid and ladders. Exact dimensions and net volume are confirmed at the quotation stage.
How much space does a 10 m³ tank need?
A 10 m³ (10,000-litre) sectional tank is 216 × 216 × 216 cm in steel; in GRP it can be, for example, 2 × 2 × 2.5 m, or 5 × 2 × 1 m where headroom is limited. To check the room, add 50 cm on every side and at least 50 cm above the tank (pp. 9, 16).
| Tank | Tank size (W × L × H) | Minimum floor area | Minimum headroom* |
|---|---|---|---|
| 5 m³ steel | 2.16 × 2.16 × 1.08 m | 3.16 × 3.16 m | 1.58 m |
| 5 m³ GRP | 2 × 1 × 2.5 m | 3 × 2 m | 3 m |
| 10 m³ steel | 2.16 × 2.16 × 2.16 m | 3.16 × 3.16 m | 2.66 m |
| 10 m³ GRP | 2 × 2 × 2.5 m | 3 × 3 m | 3 m |
| 10 m³ GRP (low) | 5 × 2 × 1 m | 6 × 3 m | 1.5 m |
| 20 m³ steel | 4.32 × 2.16 × 2.16 m | 5.32 × 3.16 m | 2.66 m |
| 20 m³ GRP | 5 × 2 × 2 m | 6 × 3 m | 2.5 m |
* Excluding the concrete base and steel skid, which are added per project. Use the same rule when drawing the tank into your plans: tank size + 50 cm clearance on every side + base.
Large tanks: 100 m³ and above
A 100 m³ GRP tank can be built as 10 × 5 × 2 m, 8 × 5 × 2.5 m or 5 × 5 × 4 m. The standard steel chart stops at 90 m³ (648 × 432 × 324 cm); above that, steel tank sizes are worked out per project under the catalogue note that intermediate sizes and special capacities are made to order (p. 15). GRP tanks use the same panel family from small to very large projects, and the catalogue's GRP connection table covers tanks of 501 m³ and above (pp. 11, 13).
The footprint does not have to be a rectangle: GRP tanks can be built in L and U shapes and around columns (p. 9). If you need two separate stores, such as drinking water and fire water, one tank with a partition panel uses the floor better, because separate tanks need 1 m between them for maintenance. In the catalogue example, two separate tanks hold 12 m³ in total, while a partitioned tank on the same area holds 16 m³ (p. 13).
Clearances, access and the concrete base
Leave at least 500 mm between a sectional tank and any wall, column or ceiling; the catalogue gives the same clearance for GRP and steel tanks (pp. 9, 16).
- Wall and column clearance: 500 mm minimum
- Ceiling clearance: 500 mm minimum
- Between two separate tanks: 1 m for maintenance (p. 13)
- Concrete base for GRP tanks: compressive strength of at least 180 kg/cm², levelling mortar no thicker than 20 mm (p. 13)
The tank sits on a steel support grid over a concrete base that is prepared on site to suit the tank size (pp. 9, 10). Because the tank arrives as panels, it can be carried through narrow doorways and assembled inside (p. 4), so measure the access opening as well as the room. When checking headroom, add the height of the concrete base and steel skid to the tank height and the 500 mm top clearance; that height is set per project. Read more in our installation guide.
Standard connection sizes by capacity
Connection sizes grow with tank capacity: in the catalogue's standard table, a 1–10 m³ tank has a DN 25 inlet and DN 50 outlet, while a tank of 501 m³ or more has a DN 125 inlet and DN 150 outlet (p. 13). Our installation guide lists the standard inlet, outlet, overflow and drain sizes for every capacity band from the GRP section of the catalogue.
Connections are supplied flanged or threaded, and sizes can be changed to suit the project. Pipework must be supported separately so that it puts no load on the tank (p. 13).
What we need to size your tank
To propose the right tank size and layout, we need the details listed in the catalogue (p. 23):
- Required capacity (m³)
- Tank type: GRP, galvanized or stainless steel
- Width, length and ceiling height of the room
- Width of the door or opening the panels will pass through
- Location: indoors, rooftop or outdoors
- Use: drinking, fire, utility or process water
- Whether thermal insulation is needed
Send them through our quote form and we will reply with a recommended size and layout.
Frequently Asked Questions
What size is a 10,000-litre sectional water tank?
In steel, the catalogue size for 10 m³ is 216 × 216 × 216 cm (p. 15). In GRP, a 2 × 2 × 2.5 m tank gives 10 m³, or 5 × 2 × 1 m where headroom is limited. Add at least 50 cm clearance on every side and above the tank.
What are standard GRP panel tank dimensions?
GRP panels are 1,000 × 1,000 mm, with a 1,000 × 500 mm half wall panel (p. 11). Width and length follow the 1,000 mm panel module, and height is chosen from 1.0 to 5.0 m in 0.5 m steps (catalogue pp. 5, 8, 11). The catalogue's partitioned-tank example also shows 2 × 1.5 × 2 m tanks (p. 13), so half-metre plan dimensions may be possible; confirm the exact footprint for your project with us. For example, a 2 × 2 × 2.5 m GRP tank has a gross volume of 10 m³.
How heavy is a full 10 m³ water tank?
The water alone weighs about 10,000 kg, since one cubic metre of water is roughly one tonne. The empty weight depends on material and layout and is not listed in the catalogue. GRP has a density of 1.8 kg/dm³ against 7.85 kg/dm³ for steel, so a given volume of GRP weighs about a quarter as much (pp. 5, 8). Plan the base for the full weight of tank and water.
How much clearance does a sectional tank need?
At least 500 mm to walls, columns and the ceiling, for both GRP and steel tanks, and 1 m between two separate tanks for maintenance (pp. 9, 13, 16). Also measure the door or opening the panels will pass through: the tank arrives as panels and is assembled inside, which is how it can pass through narrow doorways (pp. 4, 23).
What is the smallest sectional water tank?
The smallest size in the catalogue's standard steel chart is 1.26 m³: a 108 × 108 × 108 cm cube, one panel on each side (p. 15). The next standard size is 2.50 m³ (108 × 216 × 108 or 108 × 108 × 216 cm). The catalogue gives no minimum capacity for GRP; panels are 1 × 1 m, the lowest tank height is 1.0 m and each tank is sized per project (pp. 8, 11).
Get a quote for your project
Share the required capacity (m³), application and location; our engineers will reply with a recommended panel type, size and material.