If your main roof isn’t ideal for solar panels – whether due to size, orientation or shading – your garage roof could offer a practical and highly effective alternative. Across the South East, more homeowners are choosing to install a solar PV system on a garage or outbuilding to unlock extra generation potential and further reduce reliance on the gird.
A garage roof often provides underused space that can be transformed into a reliable source of clean electricity. However, as with any solar installation, there are key technical and practical considerations to assess before proceeding. This guide explains everything you need to know about installing solar panels on a garage roof and whether it’s the right option for your property.
Is a Garage Roof Suitable for Solar Panels?
From a technical perspective, installing solar panels on a garage roof follows the same principles as installing them on a house. The difference lies in access, wiring and sometimes structural condition. Before installing a solar PV system on your garage, the following factors need to be assessed.
Garage Roof Size
The available roof area determines how many solar panels can be installed. A typical UK garage measures around 5m x 3m, offering around 15 square meters of usable space. This is usually sufficient space for 8 solar panels, depending on the panel brand and wattage.
Roof Orientation and Pitch
In the UK, south facing roofs generate the highest annual solar output. That said, east- or west-facing roofs can still perform very well, particularly when combined with battery storage. Roof pitch also matters. An angle between 30° and 40° typically delivers the best year round performance in the South East climate.
Shading and Obstructions
Solar panels perform best with minimal shading. If your garage is close to your home, trees, chimneys or neighbouring buildings, these could cast shadows at certain times of day. Even partial shading can reduce system output, so a professional solar survey is essential to identify potential issues and design the most efficient layout.
Structural Condition
Solar panels generally weigh 20-25kg each, including mounting hardware. Most garage roofs can support this additional load, but older or poorly maintained structures may require reinforcement. If there’s any doubt about structural integrity, a structural assessment should be carried out before installation.
Roof Type and Materials
Garage roof construction can affect both cost and installation complexity:
- Pitched concrete tile roofs are usually the most cost effective and straightforward
- Flat roofs require angled mounting systems to optimise panel tilt
- Slate roofs need specialist fixings, increasing labour and materials cost
- Older garages need to be assessed for materials such as asbestos, which require specialised handling before work can begin
Pros and Cons of Installing Solar Panels on a Garage
Advantages
- Easier access: single storey garages are easier to reach, simplifying maintenance and often removing the need for scaffolding
- Preserves your home’s appearance: ideal for listed properties or homes within a conservation area
- Efficient system layout: garages offer a secure location for inverters and battery storage
- Better use of unused space: turns a redundant roof into a productive energy asset
Potential Drawbacks
- Shading risks from nearby buildings or trees
- Structural upgrades may be required for older garages
- Additional cabling may be needed to connect a detached garage to your home’s electrical supply, sometimes involving trenching or sub-boards
Best Garage Roof Types for Solar Panels
South-Facing Pitched Roofs
The most efficient option, delivering strong solar generation throughout the day.
East-West Pitched Roofs
Panels can be split across both sides to capture morning and afternoon sun, producing consistent daily output.
Flat Garage Roofs
Flat roofs work well when combined with angled mounting systems. allowing panels to be positioned for optimal sunlight exposure.
In practice, most structurally sound garage roofs with low shading can support solar panels. A professional installer will design a system tailored to your property.
Planning Permission for Garage Roof Solar Panels
In most cases, solar panels fall under Permitted Development Rights, meaning no planning permission is required. As of recent updates to policy, flat roof solar installations are also now covered.
Additional checks may be required if your garage is:
- In a conservation area
- Part of a listed building
- Located in and Area of Outstanding Natural Beauty
- Subject to restrictive covenants
SolarTherm UK can advice on planning requirements during your survey.
Can Solar Panels Power and Heat a Garage?
With the correct system design, solar panels can power lighting, sockets, tools, appliances and even heating.
Electric heaters or air source heat pumps are the most practical options for solar powered heating. Heating demand is higher than standard electrical use, so correct system sizing is essential.
Cost of Installing Solar Panels on a Garage Roof
Solar installation costs vary depending on system size, roof type, distance from the main property and electrical work required. At SolarTherm UK we don’t believe in a one size fits all approach to solar, each system we design is tailored to your property, usage and future energy needs. Typically, however, most residential solar installations cost under £10,000 with a payback period of 6-10 years.
Additional costs may apply for:
- Trenching and cabling
- Specialist mounting systems
- Structural reinforcement
- Battery storage
Despite the upfront investment, garage mounted solar PV systems can deliver strong, long term savings, improve energy independence and reduce carbon emissions.
Can Garage Roof Solar Panels Power Your Home?
If your garage is connected to your home’s electrical supply, electricity generated by the solar panels can power household appliances, lighting, battery storage and EV chargers – just like a roof mounted system on your house.
Thinking About Solar Panels on Your Garage Roof?
If you’re based in Essex, Kent, Suffolk or anywhere in the South East, SolarTherm UK can design and install a garage mounted solar PV system tailored to your property. Our experienced team will assess your roof, energy usage and future plans to provide clear advice and a transparent quote.
Contact SolarTherm UK today for a free, no obligation quote and design, tailored to your property, usage and future energy needs. No hard sell, just honest, expert advice.
Your home. Your energy. Your future.
