Product

Water ballast solar mounting system

A ballasted racking system for flat roofs in which the ballast and the support are the same component: a sealed HDPE tank, filled with water on site.

Specifications

Material: HDPE, blow-moulded, one piece
Empty weight: approx. 6.3 kg
Dimensions (L × W × H): 1450 × 410 × 200 / 310 mm
Ballast per unit, filled: approx. 120 kg of water
Cavity volume: approx. 0.16 m³ per unit
Stacked volume, 2 units: approx. 0.32 m³
Ballast medium: Clean water only

Module orientation: Portrait
Mounting tilt: approx. 5°
Bracket position: Under the seam between modules
Units per row: Modules in row + 1
Clamp sets: Middle + end, by frame thickness
End clamps = units × 2
Tested wind uplift: 0.55 kN/m² (PASS)
≈ 30 m/s / 108 km/h
Design life: HDPE body with UV stabiliser

A unit filled to capacity carries about 120 kg of water. Whether your site needs full fill, partial fill or additional units depends on the design wind pressure — we issue that calculation per project.

Single water ballast bracket carrying one solar module at 5 degree tilt — Unit with module fitted, 5° tilt

Rows of ballast tanks positioned on an industrial roof before modules — Units positioned, module rows ready

Completed ballasted solar array on a factory roof — Completed array on an existing roof

System components

Four parts, no rails, no purlins, no anchors.

Component	Function
Tank (body)	Sealed HDPE box. Acts as ballast once filled and as the support for the module frames. Ribbed side walls, moulded fill port.
Middle clamp	Clamps the adjacent frames of two neighbouring modules onto the tank below them.
End clamp	Clamps the outer frame of the first and last module in each row.
Bolt	Connects clamp to tank. Single bolt, hand-tightened with a spanner — no torque wrench required on the roof.

Installation

Four steps, two people, one row at a time.

No drilling, no cutting, no welding on site. The sequence is the same for a 20 kW roof and a 1 MW roof, it just repeats.

Position tanksLay out along the row at module pitch. Empty units are moved by hand.

Place modulesPortrait, dropped onto the seams between tanks.

ClampMiddle clamps at seams, end clamps at row edges, one bolt each.

Fill with waterSite tap or bowser. Fill level per our ballast calculation.

CommissionDC strings, inverter, as normal. Membrane never touched.

0

Holes in the roof structure

0

Cranes or hoists required

2

Workers per row

Testing and compliance

Test	Condition	Result
UV ageing	1000 h, UVA-340 GB/T 16422.3-2022	8 h light at 60 °C / 4 h condensation at 50 °C × 84 cycles. No cracking, no chalking, no significant discolouration.
Cold exposure	−40 °C × 168 h	No damage, no cracking.
Dry heat	105 °C × 200 h	No significant surface defects.
Thermal cycling	−40 ↔ +85 °C, 200 cycles IEC 61215-2:2016 MQT 11	No significant surface defects.
Wind uplift / pull-out	0.55 kN/m² (≈ 30 m/s, 108 km/h)	No tearing or failure at the clamp. PASS. Report JTTR-PZ-A-04-003.
Third-party verification	Tianjin Bailun, CMA/CNAS	Report BL9B936C52, issued 2026-10-12, conclusion PASS.

Wind resistance

0.55 kN/m² in wind-speed terms

Tested pressure converted at standard air density (ρ = 1.225 kg/m³, 15 °C, sea level) using q = 0.5ρv².

Wind speed	Dynamic pressure	Beaufort	Against tested 0.55 kN/m²
20 m/s (72 km/h)	0.245 kN/m²	8	Within tested range
25 m/s (90 km/h)	0.383 kN/m²	10	Within tested range
30 m/s (108 km/h)	0.551 kN/m²	11	At the tested limit
35 m/s (126 km/h)	0.750 kN/m²	12	Above tested range — ask us
40 m/s (144 km/h)	0.980 kN/m²	12+	Above tested range — ask us

Check the design wind speed or design pressure your local code requires for the building. If it falls inside the tested range, the system fits mechanically. Above it, talk to us about extra units or a different configuration. The final ballast calculation is issued per project.

Downloads

Documents for your tender file.

Technical datasheet

Two-page A4 summary: dimensions, weights, loading, testing. Suitable for printing or attaching to a submittal.

Open datasheet →

Product brochure · PDF, 6 pages ↓

Test report & patent

CMA/CNAS report BL9B936C52 and patent certificate 202630294473.0 are sent on request against your project details.

Request copies →

Layout & unit count

Send a roof drawing and module datasheet. We return a layout drawing, unit count and ballast calculation.

Request a layout →

Not sure how many sets your roof needs?

Use the calculator for a first estimate, then send us the drawing for the exact layout.

Open the calculator