In Balance Energy

Solar & Electrical | Services & Systems

Home Services Systems About Contact


Solar PV: Safety and The Building Regulations

Installing a Solar Photovoltaic System presents a unique combination of challenges. In addition to the risks associated with dealing with live electricity (you can't turn solar PV panels off!). The installer is also faced with the dangers of handling potentially large and heavy equipment at height as well as ensuring that the installation of a solar PV system does not have a negative impact on the strength and integrity of the buildings structure (often a roof) where the system is to be mounted.

Back to Articles

Solar PV Array Warning Label


This short article is not meant to be a complete guide to the building regulations in relation to installing photovoltaics. Our intention in writing this article is to provide a focus on solar photovoltaics, an area where specific guidance is hard to find and highlight potential discussion points between the client and the installer in order to ensure that PV installations are safe and compliant. We reference the Building Regulations and other relevant legislation in this article and have provided supporting links and documentation for further review at the end.


The Building Regulations cover aspects of building such as fuel conservation and the accessability and usability of buildings but their overriding concern is for people's safety. In law, responsibilty for compliance with the building regulations lies firmly with the person carrying out the work. But let's take a step back, we are talking about people's safety, could being able to blame someone else in court for non compliance in any way compensate for a serious accident or a death?

It is important for both clients and installers to know what the building regulations are, what they are used for, the protections they offer and how to ensure that the installer and the installation is compliant and subsequently safe. Any good installer will welcome discussions with an educated and interested client and will have a professional interest in delivering the safest possible installation in compliance with the Building Regulations.

The Building Regulations

The Building Regulations 2000 were made under the Building Act 1984 and are applicable in England & Wales. The requirements of the Building Regulations (Scotland) 2004 apply in Scotland. The Building Regulations (Northern Ireland) 2000 (as amended) apply in Northern Ireland. Although from now on we only reference the Building Regulations for England and Wales we hope the points and examples highlighted are relevant to anyone installing a solar photovoltaic system wherever they may be located.

Building Control & Local Authorities

Local authorities are responsible for compliance with the Building Regulations and most will have a dedicated building control department. There is some confusion as to whether a solar PV installation needs to be notified to the local authority and different authorities do have different approaches.

To clarify, what is certain is that nearly all domestic electrical work is notifiable under Part P of the Building Regulations (see below) and a solar PV installation is nearly always notifiable electrical work. Notification can be carried out either by your installer after the work has been carried out if they are recognised as a competent person under Part P (look for membership of a competent persons scheme such as NICEIC, NAPIT, ELECSA). If your installer isn't registered as a competent person or you are carrying out the installation yourself you will need to inform building control in advance by filing a building notice.

The confusion comes in as a solar PV installation is often much more than electrical work, for example some installations involve major roofing work and other structural changes especially when integrating photovoltaics into a building's fabric. This work goes beyond Part P and electrical installations, we are now talking about building work.

Wether this building work has to be notified is dependent on the nature of the work and the preference of the local authority, in our experience it is in everyone's interest to notify or at least clarify in advance if there is any doubt. The costs involved in filing a building notice are small when compared to the cost of a system and in our experience solar PV applications are welcomed and treated positively.

The benefits of involving building control include; a record of the building work will be kept with the local authority for review by any prospective house purchaser via a local authority search, avoiding any potential difficulties when selling a property in the future. Paperwork, certifications and equipment will be double checked by an independent third party and everyone will have the comfort of knowing the installation has been carried out correctly, safely and in compliance of the Building Regulations.

The Regulations

The Building Regulations 2000 are split into 14 parts A-P, depending on the nature of the PV installation the following parts may be applicable and should be addressed early at the system design stage:

Part (Click to download) Examples

Approved Document A - Structure

  • Strength of roof e.g. increased weight loading
  • Effect of wind lift on solar PV panels & roof supports
  • Depth of wall chases
  • Sizes of holes and notches used for cables
  • Use of certified and correctly applied materials and equipment

Approved Document B1 - Fire Safety (Domestic)

Approved Document B2 - Fire Safety

  • PV installations in relation to fire risk e.g short circuits, overloaded cables.
  • Fire resistance of roof coverings esp roof integrated PV panels, PV tiles & PV slates
  • Cable penetrations through walls, ceilings and floors must not assist the spread of fire
  • Adequate ventilation of heat producing equipment e.g inverters, PV modules and PV Cables.
  • Use of certified and correctly applied materials
Approved Document C - Moisture
  • Cable penetrations through external walls and prevention of moisture ingress.
  • Moisture ingress through roof coverings
  • Correct choice, use and application of moisture prevention e.g. roof flashings, waterproofing
Approved Document E - Sound
  • Sound passage through cable penetrations should be minimised and gaps sealed.
Approved Document F - Ventilation
  • Correct positioning and ventilation of heat emiting equipment such as inverters, solar panels and cables.
Approved Document K - Protection from Falling
  • Safe installation of solar PV systems at height
  • Safe maintenance of solar PV systems at height
  • Correct selection, construction and use of access equipment such as scaffolding
Approved Document M - Access & Use of Buildings
  • Accessable placement of equipment e.g. Inverters, monitors, fuse boxes, isolators
Approved Document P - Electrical Safety (Domestic)
  • Correct usage, sizing and positioning of cables
  • Labelling and warning signs
  • Adequate earthing and bonding (if required)
  • Protection from damage, dust, water and people (esp fingers) of electrical equipment and cables.
  • Test certificates, manuals and safety instructions
  • Isolation arrangements (how to disconnect parts or all of the system)
  • Correct selection and use of protective devices such as RCDs, fuses and isolators

Official guidance to the different parts of the Building Regulations can be downloaded by clicking the links to the Approved Documents above. Your Local Authorities website or building control department may also have further information and guidance.

Other free documentation that may be useful for clients and installers in relation to installating solar photovoltaics safely and in compliance with the Building Regulations can be downloaded below.

Top of page

Professional Solar PV System Design & Planning

The success of any renewable energy project is always in the quality and robustness of the system design, our experienced in-house design team has been designing innovative and ground breaking solar PV and other renewable energy systems since 2007.

Solar PV System Design
We take a collaborative and open approach and often find the very best systems are those where the system owner/developer has taken an active involvement with the design.

We can help prepare cost effective designs, roof layouts and documentation for all types and size of solar PV project; including drawings, bills of materials and detailed custom installation/owners manuals. We work with installers and developers as well as private clients and businesses, so if you need any technical information prepared then contact us, we have specialist knowledge and experience at your disposal, you will find us easy to work with and happy to help.

Solar PV System Design & Planning

Solar PV Equipment and Installation Kits

If we are supplying systems and equipment to Solar PV installers or for DIY solar installations, we are always happy to include system designs, testing and bespoke documentation as part of the package.

Solar PV Equipment Suppliers
This can include:
  • System Performance Statements
  • Line Drawings and Schematics
  • Roof Layouts
  • Grid Connection Documents
  • Solar Panel Testing and Records

Solar PV Systems & Equipment



Further reading and calculators related to designing, installing, repairing and maintaining solar photovoltaic and electrical systems:

Engineering Recommendation G98

Grid Connections for Micro-Generators including Solar PV Systems and Elecricity Storage Systems in the UK. Under 16Amps Per Phase, grid synchronised.

Types of Solar Photovoltaic (PV) System

Introduction to the different types of Photovoltaic (PV) System available including Grid Tied, Off-Grid, Hybrid and Batteryless solar PV systems.

Solar PV System Components

Overview of the basic components needed to install a complete solar PV system. Introduction to solar PV panels. power inverters, AC & DC isolators and mounting systems.

Free Solar PV Calculators

A list of free solar PV calculators, solar design tools and software, Use to calculate solar yields and the Return on Investment (ROI) for solar PV systems.

Evaluating Solar PV Panels - Which panels to buy?

What to look for when evaluating and selecting solar PV panels for UK installations. Electrical characteristics of solar PV arrays and the safety factors used for selecting BoS equipment, also mounting options.

Solar Panels - PV Array Calculator

Solar Panels: Solar PV System sizing and power yield calculator. Use to work out roof layouts, PV array sizes, No. of panels and power yields. Based on SAP 2009.

Solar PV: Smart Export Guarantee

Interesting times ... The Smart Export Guarantee came into affect in January 2020. The Smart Export Guarantee is an obligation set by the government for licensed electricity suppliers to offer a tariff and to pay small-scale low carbon Generators and Micro-generators for any electricity that they export to the National Grid.

Flat Roof Solar PV Array Spacing / Shade Calculator

The minimum required space between parallel rows to avoid shading is decided by the height of the array immediately in front, the slope of the roof and the lattitude of the installation site. This table illustrates the different row spacings required for optimum positioning in different locations.

Solar Electricity - Frequently Asked Questions (FAQs)

How to size a system?, What is kWp?, What is the difference between a kilowatt (kW) and a kilowatt hour ( kWh)?, How does a solar PV system work? Can I add more solar panels to my system? How do I know if my solar panels are working?

Preparing for a Solar Panel Installation

As with any construction project the success and efficiency of a solar PV panel installation comes down to good planning. Some advice for potential system owners preparing for a new solar panel installation.

Planning Permission for Solar Photovoltaic (PV) Systems

A solar PV installation can be classed as 'permitted development' subject to conditions and when not located within a conservation area, AONB or world heritage site.

Safely Retrofitting Solar PV Roof Mounts

The things to consider before installing a retrofited solar PV system on a roof and an introduction to the type of equipment used to secure an on-roof solar PV system.

Smart Switching / Solar PV Power Switching

Available as an addition to existing solar PV systems or installed as a package alongside a new system, Smart switching puts full control of a solar PV system's power output firmly in the hands of the system owner.

Solar Photovoltaic (PV) & Electrical Glossary of Terms

An alphabetical list of many of the industry and technical terms you are likely to come across when installing a solar PV system. The glossary also defines terms that are used in roofing and electrical work as well as in solar PV installation and solar manufacturing.

Mains Power Supplies & Earthing Systems

Mains Supply and Earthing Systems: Location & accessability, supply systems, earthing, bonding, labelling, installing RCDs.

Electrical Warning Signs & Labelling

A quick overview of some common electrical warning signs and labels that you might find attached to electrical equipment.

ABB / Power One Aurora Inverter Faults and Repairs

Power One, at one point were the second ranked inverter manufacturer in the world and there are many Power One Aurora Inverters installed in the UK. The most popular models being the Uno PVI-3.0-TL-OUTD and the Uno PVI-3.6-TL-OUTD.

Fronius IG / IG Plus Inverter Faults and Repairs

Fronius IG and IG Plus series inverters have LCD displays on the front of the chassis that providing it's working, will highlight any errors with the inverter or the solar PV system that it runs.

Mastervolt Inverter Faults and Repairs

Mastervolt Sunmaster and the smaller Soladin ranges of inverters were widely installed in the UK between 2011 and 2014. Popular Sunmaster models being the Sunmaster XS2000, Sunmaster XS3200 and the Sunmaster XS4300.

SMA Sunnyboy Inverter Faults and Repairs

SMA Sunnyboy Inverters have been widely installed in the UK, some of the most popular being the SB1200, SB2000 and SB3000. High frequency models include the SB2000HF, SB2500HF, and SB3000HF. Transformerless models include the SB3000TL and the SB3600TL.

SolarEdge Inverter and Optimser Faults and Repairs

The SolarEdge system is unique and in our opinion unrivalled in terms of it's ability to monitor system performance down to panel level. This is achieved through the installation of a small unit called an optimiser.

Sonnen Macht Inverter Faults and Repairs

The problem we often find with these inverters are damaged relays, the tell tale sign of a relay failure is an Error 19: Relay or Error 19: Relay Fault warning displayed on the inverter's display.

Top of page

Areas Served:

Swindon: Abingdon, Aldbourne, Andover, Banbury, Basingstoke, Bath, Berkshire, Bicester, Blunsdon, Box, Bracknell, Bradford on Avon, Bristol, Burford, Calne, Camberley, Carterton, Cheltenham, Chippenham, Chipping Norton, Chipping Sodbury, Cirencester, Corsham, Cricklade, Devizes, Didcot, Evesham, Faringdon, Fleet, Gloucester, Gloucestershire, Hampshire, Henley-on-Thames, Highclere, Highworth, Hook, Hungerford, Keynsham, Kingsclere, Lambourn, Lechlade, Lyneham, Maidenhead, Malmesbury, Marlborough, Marshfield, Melksham, Minety, Newbury, Oxford, Oxfordshire, Pewsey, Purton, Ramsbury, Royal Wootton Bassett, Salisbury, Shalbourne, Slough, Stow, Swindon, Tewkesbury, Thatcham, Trowbridge, Wanborough, Wantage, Warminster, Wiltshire, Winchester, Windsor, Witney, Wokingham, Worcester, Wroughton and Yate.

Residential - Commercial - Agricultural - Industrial

©2007 - 2021 In Balance Energy