T-Frame Solar Canopy

What Is a T-Frame Solar Canopy?

A T-frame canopy gets its name from the T-shaped cross-section of the structure. A central column supports a horizontal ridge beam (the top of the T), from which two rafters slope downward in opposite directions — one on each side of the drive aisle.

This design allows a single column row to cover two parallel rows of cars (plus the drive aisle between them), maximising coverage efficiency and minimising the number of column foundations required.

Why Choose a T-Frame?

T-frame canopies are particularly well-suited to:

East-west oriented car parks: Where vehicles park nose-to-nose with a drive aisle between them, a T-frame covers both rows from a single central column spine. Panels face both east and west — the east side captures morning sun, the west side captures afternoon sun. Daily generation profile is flatter than mono-pitch but total output is 92-95% of a south-facing mono-pitch.

Symmetrical aesthetics: The T-frame presents the same profile in both directions — useful on sites where the canopy is visible from multiple public aspects.

Limited column positions: Where the car park layout restricts where columns can be placed (due to service runs, drainage, parking tolerances), the T-frame's central column approach often works where perimeter columns would not.

Structural Design

Standard T-frame specification:

Panel Configuration

T-frame canopies typically use monofacial panels (bifacial panels gain less relative benefit than on cantilever structures). A standard 10m span T-frame covering 2 x 5m bays accommodates:

• 4 panels per rafter at 2.1m x 1.1m (standard 420 Wp)
• 2 rafters per column bay (10m rafter spacing = 1 column per 10m of bay length)
• Approximately 3.2-3.6 kWp per car bay covered

Performance vs Mono-Pitch

In a standard UK setting, a T-frame covering equal numbers of bays generates approximately 92-95% of what a south-facing mono-pitch produces. The 5-8% yield difference reflects the compromise between east and west panel faces versus an optimal south pitch.

For most businesses, this is an acceptable trade-off given the T-frame's structural efficiency advantage (fewer columns, larger clear spans, one set of foundations serving two rows of bays).

Planning

T-frame canopies typically have a lower ridge height than mono-pitch for equivalent bay coverage (the ridge is over the drive aisle rather than at the perimeter). In England a T-frame over a non-domestic car park can use Class OA permitted development, provided no part exceeds 4 metres above ground level and the prior approval application — on siting, design, appearance and glare — succeeds; our planning guide for car park canopies sets out the full limits. The symmetric, enclosed profile is often easier to present in planning contexts than an asymmetric mono-pitch.

Get a T-Frame Feasibility

We design T-frame canopies for UK commercial car parks of all sizes. Free desk-based feasibility within 5 working days includes structural scheme design, PVSyst yield model, and 25-year financial DCF.