System Types
T-Frame Solar Canopy
The T-frame canopy uses a central column spine with panels sloping in both directions — ideal for east-west oriented car parks or where a symmetrical appearance is required. One structure covers two rows of vehicles.
Get a T-frame designIn short: T-frame canopies cover two rows of bays from one central column line — the best kWp density per pound on large flat car parks, at ~92–95% of mono-pitch yield.
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:
| Element | Specification |
|---|---|
| Central column | 200x200 SHS or 250x250 SHS, hot-dip galvanised |
| Ridge beam | RHS 200x100 or I-section, structural S355 |
| Rafters | IPE 160-200, welded to ridge beam |
| Purlins | Galvanised Z-section at 900mm |
| Foundation | Twin concrete pile (one per column, deeper for moment loads) |
| Clear height | 2.4m at eaves (perimeter) |
| Span | Typically 10-13m centre-to-centre (5-6.5m each side) |
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). Standard T-frames comply with Class J PD criteria. 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.