EPISODE: 032 - APPROVED DOCUMENT P - ELECTRICAL SAFETY - DWELLINGS

BYTNAR - TALKS

EPISODE 032 - APPROVED DOCUMENT P - ELECTRICAL SAFETY - DWELLINGS

This episode is for people who want to know more about Approved Document Part P – Electrical Safety.

You should like this episode if you ask yourself questions like:

• What is Approved Document P and how does it promote electrical safety in dwellings?

• What standards must electrical installations follow according to Part P of the Building Regulations?

• What types of electrical work require building control approval under Part P?

• Are there specific requirements for the design and installation of low and extra-low voltage systems?

• How do existing electrical installations need to be evaluated during upgrades or extensions?

• What is the process for inspecting and certifying electrical installations under BS 7671?

• Can homeowners self-certify their electrical work, and if so, what are the qualifications needed?

• What are the consequences of non-compliance with Part P of the Building Regulations?

• Are there any exceptions in Part P for certain types of buildings or electrical installations?

LET'S TALK ABOUT YOUR PROJECT

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This is Bytnar Talks: The Engineer Takes on Construction – Episode 32

Hi, I'm Piotr Bytnar.Each day, I help my clients plan and design building projects through Bytnar Limited – a consulting Chartered Structural Engineers practice.

My biggest passion, and the cornerstone on which I've built my business, is finding clever solutions for construction projects.

I am a Chartered Structural Engineer and a budding software developer, so you can rest assured that I will strive to talk about the best practices and the use of new technologies in the industry. And if you're embarking on a construction project, or are involved in planning, designing, and building the world around us, you'll find this podcast useful.

Approved Document P: Electrical Safety – Dwellings

Hi guys, and welcome to Bytnar Talks – your favorite podcast on all matters of architecture, engineering, and construction.It is Thursday, the 24th of October 2024, and I'm back with you with the 32nd episode and information on Approved Document P: Electrical Safety.

It is now official – we've reached the time of the year when days are too short to care, and the air feels musty.On the other hand, Guinness tastes better, and steak dinners feel particularly good – not to mention a cheeky mincet pie here and there.

It is the time to start planning your projects starting in spring, especially if you need to go through the regime of planning permission.As ever, let's start with a small recap of the last episode before we move to today's.

In the last episode, I talked about Approved Document O: Overheating.In Section 0 of that document – per usual – which covers the introduction, we found out that the document covers what? Overheating, right?The prevention of overheating in new residential buildings, including homes, flats, care homes, and school accommodation.It addresses communal spaces and mixed-use areas, in coordination with building control, ensuring a balance between safety, ventilation, and heat management, while considering other building regulations.So it doesn't work on its own – you've got to take into consideration other aspects too.

In Section 1, we are taken through a simplified method of dealing with that requirement, which offers a checklist contained within Appendix B of that document.The checklist leads us to reduce overheating in our property, focusing on the location of it and the type of ventilation.

It uses strategies like glazing restrictions, shading, and window openings help limit solar gain and manage heat within the building.This method is best for standard buildings but may not suit those with high heat loads coming from the services of that building.

Section 2 deals with dynamic thermal modeling, which follows the CIBSE TM59 methodology and allows for more detailed evaluation – flexible analysis, if you like.Particularly for well-insulated or airtight buildings, it may be better to use this method than go with the simplified one.It emphasizes passive measures like shading and natural ventilation, with mechanical systems used only if necessary.

Section 3 leads us to additional considerations for buildings where the simplified method isn't suitable.Additional factors – like noise, air quality, security, and window safety – must also be considered.This includes secure ventilation options and protections to prevent accidents or security risks.

Section 4 tells us about the information we need to provide to the homeowner, which must be non-technical – in the form of a non-technical manual explaining the overheating mitigation strategy for the building.This should be part of the home user guide and should offer clear instructions on operation, maintenance, and how to keep cool during hot weather.

In this episode, I will move to Approved Document P: Electrical Safety in Dwellings.So without further ado, let's dive straight into this.

In this episode, I'll talk about the statutory guidance contained within Approved Document P: Electrical Safety – Dwellings.The document covers the requirements of Part P, and it is contained within three sections.It also references the requirement of notification of works under Regulation 12.6(a).

The general play of the game is: go get yourself an electrician who will be able to work to the British Standard 7671: Requirements for Electrical Installations – right now in its 18th edition.

But listen up to find out a little bit more. So let's get into the nitty-gritty of the approved document.

All right guys, starting with the text of the legislation: Part P – Electrical Safety: Design and Installation Requirement (P1)

Reasonable provision shall be made in the design and installation of electrical installations in order to protect persons operating, maintaining, or altering the installations from fire or injury.

The requirements of this Part apply only to electrical installations that are intended to operate at low or extra-low voltage and are:A) in or attached to a dwelling;B) in the common parts of buildings that contain one or more dwellings (excluding power supplies to lifts);C) in a building that receives its electricity from a source located within, or shared with, a dwelling; orD) in a garden, or in or on land associated with a building, where the electricity is from a source located within or shared with a dwelling.

Simple: make sure buildings don’t burn and people are not electrocuted.And you are bound by the regulations. The Secretary of State thinks just that.

As long as the low-voltage and extra-low-voltage electrical installations are designed and installed so they cannot be easily damaged—mechanically or thermally—and are not hazardous in terms of fire and electric shock, the installation is compliant.

Extra-low voltage is considered to be not exceeding 50 volts alternating current (AC) or 120 volts ripple-free direct current (DC) between conductors, or between conductors and earth.

Low-voltage installations are considered to be up to 1000 volts AC or 1500 volts DC between conductors, or 600 volts and 900 volts respectively between conductors and earth.

Straight up, in Section 1, which deals with design and installation, we are told that:

• Design and installation must be in line with BS 7671,

• Sufficient information about the installation must be provided to allow people to operate, maintain, and alter it reasonably safely.

What to include is listed in the British Standard, but should include:

• An installation certificate giving details of the installation and the work carried out,

• Permanent labels on connections and bonding points,

• Electrical equipment like the consumer unit and residual current devices (RCDs),

• Operating instructions, a log book, and detailed plans (but only for unusually large or complex installations).

It should be noted: it’s all about safety here—not about functionality.

For new dwellings, the position of wall-mounted socket outlets, switches, and consumer units should be easy to reach, in line with Part M of the Building Regulations.That's roughly 450 to 1200 mm above floor level for general outlets, and 1350 to 1450 mm above floor level for the consumer unit.

A material change of use will require an assessment of the existing installation and will likely lead to the necessity to bring it up to speed with current standards.As long as it is safe, the existing installation can remain in place, even if the color codes do not match current standards.

When we alter the existing installation or add to it, as long as the old installation is of sufficient quality and capacity, we may not need to upgrade it—but it does need to be assessed.

The assessment will include:

• The rating and condition of existing equipment,

• The consumer unit and electrical distribution gear,

• Ensuring it has the capacity to carry the increased load,

• Confirming adequate protection measures are in place,

• And that earthing and equipotential bonding arrangements are satisfactory.

Now, Section 2 deals with the application of Part P, and it sets out:

• The types of buildings and electrical installations within the scope of these requirements,

• And the type of electrical work that is notifiable and must be certified as complying with Building Regulations.

So, for application, think:

• Inside and outside of a dwelling house,

• Flats, sheds, detached garages, and greenhouses,

• Common access areas and shared amenities,

• But also business premises (other than agricultural buildings) connected to the same meter as the installation of the dwelling.

However, Part P does not apply to businesses metered separately from the dwelling.Power to lifts in blocks of flats is also excluded from consideration.However, a single dwelling lift will likely use the meter of the dwelling house—so will fall under consideration.

In gist: if it is connected to the meter of the dwelling, it is considered under Part P.

The notifiable work is dealt with under Regulation 12.6A, which says—and I’ll read its content now:

Regulation 12.6A:A person intending to carry out building work in relation to which Part P of Schedule 1 imposes a requirement is required to give a building notice or an application for building control approval with full plans, where the work consists of:

A) the installation of a new circuit,B) the replacement of a consumer unit

C) any addition or alteration to existing circuits in a special location.

Now, Point 9 of Regulation 12 tells us what that special location is, and it says:

In this regulation, “special location” means:

A) Within a room containing a bath or shower —The space surrounding a bathtub or shower head, where the space extends:

• i) Vertically, from the finished floor level to:

  • (aa) a height of 2.25 m, or

  • (bb) the position of the shower head where it is attached to a wall or ceiling at a point higher than 2.25 m;

• ii) Horizontally:

  • (aa) where there is a bathtub or shower tray: from the edge of the bathtub or shower tray to a distance of 0.6 m;

  • (bb) where there is no bathtub or shower tray: from the centre point of the shower head (where it is attached to the wall or ceiling) to a distance of 1.2 m.

B) A room containing a swimming pool or sauna heater.

It’s self-explanatory really, isn’t it?And you can view a diagram that shows a standard bathroom with the zones illustrated in the document.

Naturally, the zones where the work will be notifiable will differ depending on whether there's a shower tray or bathtub, and whether the shower head is higher than 2.25 metres above the floor level — so keep that in mind.

So, all other work to the installation is not notifiable.That includes things like:

• Additions and alterations to existing installations outside of special locations,

• Replacements, repairs, and maintenance anywhere.

However — just because the work is not notifiable does not mean it does not fall under Part P.Just mind that when adding things to your circuits — if the circuit cannot operate safely, you cannot connect or extend it.Simple.Even if it’s just connected by a plug with a standard fuse — that still counts as an extension of the circuit.

Section 3 deals with certification, inspection, and testing.

To discharge the duties under Requirement P, we can either:

• Self-certify if we are a registered competent person,

• Use a third-party certifier, or

• Let the building control body certify the work for us.

In any case, the installation must be inspected and tested to procedures within BS 7671.Electrical inspection and testing forms should be given to the person ordering the work, and certificates must be issued to the occupier.

So, in the case of self-certification:

• The installer’s registration body must, within 30 days of the completion of work:

  • Provide a Building Regulations Compliance Certificate to the occupier, and

  • Send the certificate or its details to the building control body.

In the case of third-party certification:

• The person doing the work has 5 days to inform the third-party certifier,

• The certifier should inspect and test the installation,

• If the installation is satisfactory, the person ordering the work should receive an Electrical Installation Condition Report,

• Then, the certifier’s registered body should:

  • Provide the Building Regulations Compliance Certificate to the occupier, and

  • Send the certificate or its details to the building control body.

When building control is the one giving certification:

• The installer needs to notify the building control body before the work begins,

• The building control body will assess the extent of inspection and testing required,

• It may choose to have the work carried out by a specialist contractor, who will provide an Installation Condition Report instead of handling it internally.

Naturally, the contracted work will need to follow:

• The British Standard, and

• The requirements of reporting.

When the building control body is satisfied that the work meets the code, it will issue the occupier with a Completion Certificate (or a final certificate, if you will).

Non-notifiable work should meet the same standards of BS 7671 as notifiable work.And if it does not, the building authority can take enforcement action.

So, keep that in mind — and be a good boy or a girl

So this is it, folks – Approved Document P: Electrical Safety.

Let’s sum it up section by section:

Part P of the Building Regulations focuses on electrical safety, ensuring that electrical installations are designed and installed to prevent fire or injury to users.

It applies to low and extra-low voltage installations in dwellings and associated structures, including common areas and gardens connected to dwellings.

Section One deals with design and installation:

• Installations must adhere to BS 7671 standards to ensure safety – not functionality,

• They should be designed to prevent mechanical and thermal damage,

• Adequate information must be provided for safe operation, maintenance, and alteration.

Special attention is given to accessibility requirements for new dwellings, and existing installations need assessment during upgrades or alterations.

Section Two deals with the application of Part P.

It applies in dwellings, including outbuildings and shared areas, but not to separately metered business premises or lifts in flats.

Notifiable work—such as:

• New circuits,

• Consumer unit replacements,

• And work in special locations like bathrooms—

requires building control approval, while non-notifiable work must still comply with safety standards.

Section Three tells us about certification, inspection, and testing.

Installations must be inspected and tested under BS 7671, and certification is required.

• Competent persons can self-certify,

• Or a third-party certifier or building control body can verify the works.

Even non-notifiable work must meet the same safety standards, and enforcement action can be taken for non-compliance.

In the next episode, we will move to Approved Document Q: Security in Dwellings.

I hope you enjoyed this episode, and that the considerations around Approved Document P: Electrical Safety are a bit clearer for you now.

No doubt I’ll be back to talk more—and in-depth—about BS 7671 in future episodes.

If you have any questions, reach out to me on LinkedIn or send me an email. I’m more than happy to help you out.

At Bytnar, we deal with planning, designing, and managing your projects, and we are always glad to facilitate a free initial consultation to steer you in the right direction.

Visit www.bytnar.co.uk and reach out to us—Whether your question is:

“Can you help me with my project?”or“What should I do?”

—we’ll be able to give you a piece of non-obligatory advice.

At Bytnar, we help our clients design and execute their dream homes or investment projects.

If your building is falling apart, though, we can also help investigate the reasons behind it, and provide you with an appropriate strategy, design, and specifications for the repair.

Thank you again for listening.Please voice up your opinions—I'm waiting for you on LinkedIn, and I want to hear from you.

See you next week.Bytnar Designs the World Around You.Toodloo! 👋

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Piotr Bytnar BEng (Hons) MSc CEng MIStructE

Chartered Structural Engineer who deals with the Architecture of buildings. His Master's Studies led him to an in-depth understanding of risk and contract arrangements in construction as well as specialist knowledge in soil mechanics.

He and his team help homeowners and property developers to design and deliver construction projects reducing waste in time and the cost. He believes that the construction project is an iterative process that can be well managed and it is best managed if all the aspects of the project definition and management are dealt with in-house or coordinated by one organisation. His team works to all stages of RIBA and ISTRUCTE stages of work and enables contractors to deliver projects on-site providing risk evaluations, methodologies for execution of works and temporary works designs.

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