Solar & Home Energy · 9 min read · Beginner

Is My Roof Suitable for Solar Panels? Orientation, Pitch, Shade & Roof Condition

Assess the practical questions that affect a solar-PV proposal before worrying about the exact number of panels or payback.

Open the related Get Your Project Right calculator

Key points & steps

  1. Start with roof condition and expected remaining life. If the covering, battens, flashing or structure needs major near-term work, coordinate that before installing an array that would later need removal.
  2. Measure the usable roof face rather than the overall building footprint. Chimneys, rooflights, vents, hips, valleys, fire/access requirements and edge clearances can reduce usable area substantially.
  3. Note roof orientation. South-facing roofs often have strong annual yield in the UK, but east/west arrays can still produce useful generation and can spread output across morning and afternoon demand.
  4. Record roof pitch because the combination of location, orientation and inclination affects annual specific yield. Use installer/MCS/PVGIS-type modelling rather than one national kWh/kWp assumption for final estimates.
  5. Assess shading across the year, not only at midday on the day of the survey. Chimneys, trees, neighbouring buildings and roof geometry can affect modules differently as the sun moves.
  6. Check the electrical route from roof to inverter/meter and likely inverter/battery locations as part of feasibility; an attractive roof layout still needs a practical electrical installation.
  7. Have the roof structure assessed where the installer considers it necessary, particularly on unusual, aged or modified roofs. The Get Your Project Right panel-fit result is geometric only.
  8. For flat roofs, allow for mounting angle, row-to-row shading, ballast/fixings, wind loads and maintenance access rather than simply dividing roof area by panel area.
  9. Once the physical site looks viable, compare array kWp, estimated annual generation, household usage, tariff/export arrangements and installation cost together.

Practical tips

  • A non-south-facing roof is not automatically unsuitable; annual yield and usage timing matter more than a simple compass rule.
  • Trees that look harmless in summer photographs may cast very different shadows in winter, and vice versa depending on sun height and leaf cover.
  • Roof-fit calculators are useful for screening but should not be treated as a structural survey or final fire/access layout.

What you may need

  • Roof dimensions
  • Orientation/pitch information
  • Photos of obstructions/shading
  • Roof age/condition records
  • Recent electricity use

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