Solar Mounting Systems

On-roof

The standard approach: anchors fixed to the rafters, rails across the anchors, panels clamped to the rails, covering reinstated and sealed. It suits tile and slate, which covers most of the clay and concrete tile, London stock slate, and a lot of flat and butterfly roofs behind parapets found across London.

In-roof

The array sits within the roof plane in place of the covering, flush rather than proud. It looks considerably better and is often preferred on new builds, re-roofs and conservation-sensitive properties, but it is more involved and the weatherproofing detail has to be right.

Flat roofs

Ballasted or tilted frames sit on the roof surface, usually without penetrating it, angled to improve output. Ballast weight and wind loading both need calculating against what the roof structure will carry.

Metal and standing seam

Clamp systems fix to the seam itself with no penetration at all. Neat where the roof suits it.

Ground mount

Where there is land and the roof will not work. Rarely relevant on a typical London plot, but worth knowing exists.