A UK roof is suitable for solar when it has enough usable light and space, can support the mounting system, remains serviceable for the installation's life, and can be connected within planning and network rules. South-facing roofs are productive, but east- and west-facing arrays can also be useful and may spread generation across the day.
The correct sequence is property survey, design, planning and consent checks, DNO route, installation, commissioning, and handover.
Direction and pitch
Solar PV uses daylight rather than heat. Direction and pitch affect how much sunlight reaches the panels and when production occurs.
South-facing roofs generally maximise annual output in the UK. East-facing panels generate earlier, west-facing panels later, and split arrays can align better with household use. North-facing roofs usually produce less and need careful modelling rather than an automatic rejection.
Ask for the annual and monthly yield for each roof face.
Shading
Chimneys, trees, dormers, neighbouring buildings, aerials, and roof geometry can cast changing shade. Winter shading can differ sharply because the sun is lower.
The survey should identify shade by time and season. Optimisers or microinverters can reduce some electrical mismatch, but they cannot create sunlight and they add equipment to the roof.
Tree growth, protected trees, neighbour ownership, and future development also deserve attention.
Roof condition and structure
Panels may remain for decades. Inspect tiles, slates, membrane, battens, rafters, previous repairs, moisture, and remaining roof life before covering the area.
Fragile materials, asbestos, non-standard tiles, shallow roofs, flat roofs, and structural concerns require specialist design. An installer should explain mounting penetrations, weatherproofing, wind loads, edge distances, fire access, and responsibility for damage.
Complete a likely re-roof first. Removing and reinstalling panels later adds cost and risk.
Space, access, and equipment location
Usable roof area is smaller than the visible rectangle because of edges, obstacles, access, and mounting requirements. Panel dimensions and orientation affect layout.
Plan safe scaffolding, cable routes, inverter location, isolators, consumer-unit access, and any battery. Inverters need a suitable environment and service access. Long or exposed cable runs may increase loss and installation complexity.
Do not approve a layout based only on an aerial image when the roof has not been adequately assessed.
Planning permission
In England, rooftop solar on houses is often permitted development under Part 14 conditions. Panels generally should minimise visual impact, remain below the roof's highest point, and satisfy projection and location limits. Flat-roof and stand-alone systems have their own rules.
Scotland, Wales, and Northern Ireland have separate planning frameworks. Listed buildings, their curtilage, conservation areas, World Heritage Sites, National Landscapes, Article 4 directions, and properties with removed permitted-development rights need specific checks.
Ask the local planning authority when uncertain. A lawful development certificate can provide formal confirmation in relevant cases.
Ownership and third-party consent
Leaseholders may need consent from the freeholder or management company. Mortgage terms, restrictive covenants, estate rules, shared roofs, party structures, and landlord arrangements can also affect permission.
For flats, roof ownership and electricity allocation make a domestic installation more complex. Obtain written consent before committing to non-refundable work.
Planning permission does not replace private consent, and private consent does not replace planning compliance.
Building regulations and electrical work
Solar work must comply with applicable building and electrical requirements. Structural loading, weather resistance, fire considerations, electrical safety, and notification need competent handling.
The MCS framework provides installation and product standards but does not replace statutory duties. Read MCS certification for solar and confirm who handles electrical certification and building-control requirements.
The DNO step
The DNO operates the local distribution network. Solar and battery inverters must follow the appropriate connection process, commonly G98 or G99.
Some smaller type-tested installations can follow an install-and-notify route. Larger or more complex proposals require application and permission before connection. Export limitation can sometimes enable a system that would otherwise exceed local capacity, but it must use an acceptable design.
Read the UK DNO application guide for the distinction.
Metering and SEG readiness
The import meter may need replacement or configuration to measure exported electricity. A Smart Export Guarantee account usually needs an export-capable meter, export MPAN, MCS evidence, and supplier application.
Metering is not a substitute for DNO notification. These are separate processes involving different organisations.
Review the Smart Export Guarantee before commissioning so the handover evidence is complete.
Survey questions to ask
- Which roof faces are used and why?
- What shade has been modelled by season?
- Is the roof condition suitable for the expected system life?
- Is structural verification required?
- Which planning rules and private permissions apply?
- What scaffolding and access are included?
- Where will inverter, isolators, cables, and battery go?
- Is the DNO route G98, G99, or another arrangement?
- Is export limited, and how does that affect generation and SEG income?
- Which certificates and drawings will be handed over?
Warning signs
Be cautious when a salesperson guarantees planning status without checking the property, ignores obvious shade, cannot identify the DNO route, treats a failing roof as irrelevant, or refuses to itemise access and electrical work.
A robust survey may reduce the headline array size. That is often better than installing panels in persistently shaded areas or creating avoidable roof work.
The best UK solar roof is the one that supports a durable, documented system whose annual output matches the household's needs and connection conditions.