Welcome to Part 2 of our series on the building regulations.

Yesterday we had a brief look at the purpose of the regs. Today we’re going to look, in more depth at exactly what they’re about

Below is a list of the Building Regulations, along with a brief description of the things they cover and common examples of how they may come into play in a typical extension. It’s not intended to be an exhaustive exposition of the building regs, more a brief overview to give you some idea of what each one is about.


Part A – Structure

I don’t think that the Building Regulations were necessarily arranged in order of importance, in fact I’m quite certain they weren’t, BUT I do think it’s appropriate that the first one is Structure.

Part A, deals with the physical structure of the building, the bits of the building that hold it up and make sure it stays stood up. Ultimately, it doesn’t matter how good a building is at anything else, if the structure is faulty then it’s simply not fit for purpose.

Anything that has any bearing on the structural stability of a building will be covered here, such as foundations, load bearing walls, steelwork, roofs all that sort of thing.

Typically, you will need to employ a Structural Engineer to design the main structural elements of the building. They’re calculations and designs will then be checked by Building Control.

As an example, if you’re building an extension on the back of your house, it’s quite likely that part or all of the existing wall will need to be removed and replaced with a steel beam of some kind. This steel will need to be designed so that it complies with part A


Part B – Fire Safety

Another very important one to get right. Part B seeks to ensure that the chances of a fire starting in a building are a low as they possibly can be but more than that, it also deals with what happens if a fire does start. So, on one hand it deals with things like materials that can and can’t be used to limit the likelihood of fire breaking out, but then, it deals with things like fire alarm systems and escape routes, so that if the worst should happen, then anyone inside the building has time to get out safely.

In a typical extension, one thing that usually has to be done is that a mains powered, interlinked fire alarm system must be installed


Part C – Site Preparation and Resistance to Contaminants and Moisture

Part C is concerned with ensuring anything that should stay outside of the building should, such as harmful gasses from the ground, and water.

In some areas Radon is present in the ground and it must be ensured that this cannot make its way into the building. In all areas in the UK moisture is present, and again, it is vitally important that it cannot be allowed to make its way into the fabric of the building.

As a practical example, your extension will need to be made as watertight as possible, using Damp Proof Membranes and the correct roof coverings. Part C will deal with this.


Part D Toxic Substances

The purpose of Part D is to ensure that Toxic Substances cannot gain passage into the building. This regulation shouldn’t have a major impact on the day to day construction of your extension as it primarily seeks to deal with the materials that are used rather than the workmanship.


Part E – Resistance to the Passage of Sound

 Part E deals with how we go about stopping sound passing from one room to another, the materials used, and the levels of workmanship required to ensure that if you’re in one room, you can’t hear the conversation the people in the next room are having.

If your extension has a bedroom and a living space next to each other, then you’ll want to know the wall between the room is built so that sound can’t readily pass through.


Part F Ventilation and Condensation

We’ve already seen that Part C looks to keep moisture that is outside of the building out. Part F looks to remove moisture that is created inside of the building.

Moisture inside the building from whatever source can be incredible harmful, particularly nowadays where we heat and insulate buildings to such a degree that the formation of condensation is a real risk. So, part C deals with means of ventilation buildings so that condensation can’t form in any harmful fashion.

In your extension, any “wet” areas, such as bathroom, or Kitchens will need to be fitted with mechanical extract fans, and windows will have to have trickle ventilators


Part G – Hygeine, Hot Water Safety and Water Efficiency

Part G is concerned with the supply of hot and cold water. Its purpose is to ensure that water supply systems are both safe and efficient.

In your extension and water supplies to kitchens or bathrooms etc. will need to comply


Part H – Drainage and Waste Disposal

 Part H is concerned with ensuring that both foul water and rainwater drainage is disposed of adequately.

Any waste water from bathrooms/kitchens etc. in your extension will need to be safely transported to a mains sewerage system or suitable storage system such as a septic tank.

Rainwater will need to be diverted away from the building into a suitable system such as a soakaway or in some cases a nearby watercourse


Part J – Combustion appliances and Fuel Storage systems

Combustion devices are any appliances that burn fuel for heating, cooking, water heating or similar. Part H ensures that these types of appliances are installed safely and are fit for purpose and that any waste gases or fumes are dealt with properly.

For example, if your proposed works include fitting a new boiler then not only will it will need to be installed correctly by a suitably qualified person, but the position of any flue needs to be considered so that you don’t end up with harmful exhaust gasses making their way back into the building.

Similarly if you’re looking to install a log burner, there are rules about how and where that can be fitted and the materials used in close proximity to it.


Part K – Protection from falling, collision and impact.

Part K deals with minimising the risk of physical injury when moving around a building. Things like stairs and ramps are covered as well as guard rails where there are significant changes in level. Glazing is also covered in Part K.

If you’re looking to convert your loft and need to install a stair case then this will be covered in Part K, it covers things like the steepness of the staircase and head room over the stair. Any glazing in your extension that is near the floor will need to be toughened glass so that it can’t smash and cause injury.


Part L – Conservation of Fuel and Power

 Part L is all about limiting Co2 omissions, so it covers things like the efficiency of heating and hot water systems that run on fossil fuels and ensures that buildings are properly insulated.

Your extension will have to have sufficient insulation in the walls, roof and floor to make sure that your heating system isn’t just producing heat that leaks out of the structure.


Part M – Access to and use of buildings

Part M is primarily concerned with ensuring that buildings are accessible and usable by everybody, irrespective of age or disability. It looks at how people will access and then move around and use buildings, particularly if they have limited mobility or are confined to a wheelchair.

Part M only applies to new dwellings and non-residential buildings, meaning that building control can’t insist that your extension complies with it. That said, you may decide there are items in there that its worth working towards. For instance, Part M deals largely with making it as easy as possible for wheelchair users to get around the house. While you may not benefit from this right now, we do have an aging population, so it’s possible that at some point in the future there may be a wheelchair user living in the house in the future. Could you “future proof” the property by broadly designing the extension such that it is accessible to wheelchair users?


Part N – Glazing Safety

Part N was withdrawn in 2013 and so no longer exists in its own right. However, its contents were essentially subsumed into Part K


Part P – Electrical Safety

As its name suggests, Part P deals with ensuring any kind of electrical work is done safely and certified by an appropriate person.

I would always advise you to employ suitably qualified and experienced tradespeople for any kind of building work, this goes double for anything to do with electrics. While many of us could hang a door or change a tap if we really had to, electrics are a different ball game. If it’s anything more involved than changing a lightbulb, get a qualified electrician to do it!


Part Q – Unauthorised Access

Part Q deals with ensuring that doors and windows are fitted in such a way and with such locking mechanisms that they can’t easily be broken into by would be intruders.

Similarly, to Part M, Part Q only applies to new dwellings, and not extensions, so building control can’t make you comply with it for your extension, however, fitting the windows and doors of your extension with locks that make it harder for intruders to get in is unlikely to be a decision you regret.


Part R – Electronic communications

 Part R seeks to ensure that buildings have the infrastructure in place to allow high speed broadband to be installed and used in the property

Broadly speaking, part R is unlikely to be applicable to your extension. It only really applies to new buildings and buildings that are “subject to major renovation works”. There is some debate about what exactly constitutes “major renovation works” and it would be worth confirming this with your local building control authority, but it does seem unlikely that building control would insist on it when you are simply doing works to your own property.


7 – Materials and Workmanship

 In addition to the “lettered” regulations above, which are specific to individual areas of work, there is also a more general overarching regulation dealing broadly with materials and workmanship.

Its aim is to ensure that materials and workmanship used/employed in construction are suitable, and where necessary certified (BSI, CEN, BBA etc.)


So thats it for part 2, we’ll be back tomorrow looking at how you go about getting building regulations approval

As always, contact us to get your project off the ground! zak@laceyarchitectural.co.uk