Ballast
Ballast blocks for ground-mount frames
Coming soon
The weight that holds a ground-mount frame in place, sold in the numbers the maker sets for your wind.
- Per block
- 18kg or more
- Gusts over 40mph
- 2 blocks
- Gusts over 80mph
- 10 blocks
Kit care · ballast
Ballast matched to your kit's frame
Ground-mount plug-in kits arrive without ballast. The weight that holds the frame down has to follow the maker's figures and the wind at your spot, so this page sets them out kit by kit.
Ballast matrix by kit frame
| Kit | Frame | Gusts over 40mph | Gusts over 60mph | Gusts over 80mph |
|---|---|---|---|---|
| Compact 460W ground kit | Ground stand | 2 × 18kg | 5 × 18kg | 10 × 18kg |
| Duo 890W ground kit | Ground stand | 2 × 18kg | 5 × 18kg | 10 × 18kg |
| Compact 515W hybrid kit | Hybrid, on the ground | Ask us | Ask us | Ask us |
| Duo 890W hybrid kit | Hybrid, on the ground | Ask us | Ask us | Ask us |
| Plus 1030W hybrid kit | Hybrid, on the ground | Ask us | Ask us | Ask us |
| Max 1260W hybrid kit | Hybrid, on the ground | Ask us | Ask us | Ask us |
Blocks of at least 18kg each: the kit maker's figures for its ground-mount stand. The maker's table doesn't cover the hybrid stand, so we get the figure for your kit. On a wall or flat roof, the hybrid stand needs a professional assessment first, and the assessor sets the fixings.
Weight and footprint
The maker's minimum is 18kg a block, and dense concrete gives that weight in a small footprint. The blocks sit on the stand's lower plates, shared between both sides.
- Cables on top of the blocks, never trapped underneath.
- Blocks clear of the microinverter.
- Level, firm ground: a patio, a gravel bed or a flat lawn.
Ten blocks weigh 180kg or more. Plan where they'll go before delivery day.
Wind in exposed spots
The North East gets some of England's strongest gusts. During Storm Arwen in November 2021, the Met Office recorded a 98mph gust at Brizlee Wood in Northumberland.
On the coast, on open hills, or anywhere the wind funnels between houses, plan for the 60mph or 80mph column. If you're not sure which applies, go up a column.
Check the blocks after any storm, and before one when a wind warning is out.
What we won't sell for mounting
- Balcony or railing brackets. These kits aren't for balconies.
- Roof or raised frames. Raised installs need a professional assessment first.
- Cladding fixings. Kits never go on clad walls.
- Straps, cable ties or bungees. They're no way to hold a panel down.
On the list
Be told when ballast goes on sale
We're choosing a supplier for dense blocks that meet the maker's minimum. Join the list and we'll email you when you can order them.
Do I need ballast on a lawn?
Yes. Every ground-mount frame needs it, whatever's under it. The number depends on the wind, not the surface.
Which column am I in?
Think about the strongest gusts your spot sees in a bad winter. Coast and hills: over 80mph. Open ground: over 60mph. A sheltered town garden: over 40mph. If in doubt, go up a column.