Solar Panels on East and West Facing Roofs: A Practical Guide

East and west facing roofs are genuinely suitable for solar panels. A single east or west facing roof typically produces around 80 to 85% of what a south-facing equivalent would generate over a year, and a home with panels on both the east and west pitch can perform excellently, particularly for households that consume electricity throughout the day rather than just at midday.

How East and West Facing Roofs Compare to South Facing

A south-facing roof in the UK catches the sun from late morning through early afternoon, producing a strong peak of generation around solar noon. That peak is useful, but it does not always align with when people actually use electricity at home. Many households are at work or school during the hours when a south-facing system is generating most of its power.

East facing panels generate more in the morning, from sunrise through to roughly midday. West facing panels pick up from midday through to early evening. Neither orientation matches the midday peak of a south-facing roof, but both orientations align more naturally with typical household activity: breakfast routines in the morning, and cooking or appliance use in the evening.

On an annual basis, an east or west facing roof at a 30 to 35 degree pitch will generate approximately 80 to 85% of the yield of an equivalent south-facing system. The exact figure depends on your roof pitch, your location in the UK, and local shading. Properties in southern England will see higher overall generation than those in Scotland, regardless of orientation.

The Case for an East-West Split System

If your property has both an east-facing and a west-facing pitch, splitting the array across both sides of the roof is worth serious consideration. The total annual generation will be close to, or in some cases comparable with, a south-facing array, but the profile of generation throughout the day is fundamentally different.

Rather than a single sharp peak at midday, an east-west system produces a broader, flatter generation curve from morning through to early evening. For households where someone is at home during the day, this flatter profile means more of the generated electricity is used directly rather than exported to the grid. Self-consumption is the key metric here: electricity you use directly is worth considerably more than electricity you export at the Smart Export Guarantee rate.

Installers sometimes refer to this as "load matching". A household that runs a washing machine at 8am, charges devices through the day, and cooks at 6pm will naturally consume more of the output from an east-west system than from a south-facing one. If you add battery storage, this advantage is reduced, because a battery can store the midday surplus from a south-facing system for use in the evening regardless.

Inverter Considerations for East-West Arrays

A standard string inverter is designed to work with panels that all face the same direction. Connecting east and west facing panels to a single string causes problems, because the panels generate at different times and the inverter struggles to optimise for both sides simultaneously. For an east-west split system, you have two main options.

• A dual-MPPT inverter: many modern hybrid and string inverters include two separate Maximum Power Point Trackers, which allows one MPPT to handle the east-facing string and a second to handle the west-facing string. This is the most common and cost-effective solution.
• Microinverters: a microinverter is fitted to each individual panel, so every panel optimises independently. This is more expensive but eliminates the string mismatch problem entirely and makes monitoring easier.
• DC optimisers: similar in principle to microinverters, optimisers are fitted to each panel and allow individual panel-level MPPT tracking before feeding into a central inverter.

Your installer will recommend the right setup for your roof. A reputable, MCS-certified installer will carry out a detailed shading analysis and size both strings appropriately for your property.

Is a South Facing Roof Really Necessary?

South-facing roofs are the textbook ideal, and they do deliver the highest annual yield for a single-pitch array. However, a south-facing roof is not a strict requirement for a viable solar installation. The financial case for solar does not rely on achieving maximum possible output: it relies on achieving a return that justifies the upfront cost over the system lifetime.

An east or west facing system generating 80 to 85% of south-facing output will still produce meaningful savings on energy bills, still qualify for the Smart Export Guarantee, and still have a reasonable payback period. The difference in yield between orientations matters less than the quality of the installation, the size of the system relative to your consumption, and the electricity tariff you are on.

To understand your specific roof, check which way your roof faces using our free tool. Enter your postcode and get an instant read on orientation and indicative solar potential, which you can then discuss with installers.

Shading and Obstructions

Shading has a bigger practical impact on east and west facing systems than orientation alone does. An east-facing roof that is shaded by a neighbouring building until 10am will lose a significant proportion of its morning generation. A west-facing roof shaded by trees from 4pm onwards will similarly underperform in the afternoon.

Before committing to an installation, ask your installer to carry out a site survey that includes a shading assessment at different times of year. Shading in winter, when the sun is low, can affect panels that are completely clear of shade in summer. This is particularly relevant for east and west facing roofs where the sun is already at a lower angle relative to the panels compared to a south-facing installation.

Roof Pitch and Its Effect on Yield

For a south-facing roof, the optimal pitch in the UK is typically 30 to 35 degrees. For east or west facing roofs, a similar pitch still performs well, though the angle affects how much morning or evening sun is captured. Steeper pitches on east-facing roofs can help capture low morning sun; shallower pitches on west-facing roofs can help retain some output into late afternoon.

Most UK homes have pitches in the 30 to 45 degree range, which is workable for any orientation. Very shallow pitches, below about 15 degrees, can cause self-shading as panels closer to the roof peak cast shadows on lower panels, and can also lead to dirt accumulation that reduces output over time.