Your guide - internal renovation

An internal renovation is a great way to transform your home without having to extend. Whether it's remodelling the entire space or simply replacing the kitchen or bathroom, you can dramatically change the appearance of your home and make the most out of your living space. 

Read our handy guide to help get you started!


Do I need planning permission?

Most internal renovations don’t require planning permission and are considered to be within the permitted development. This includes work such as replacing a kitchen, bathroom or knocking down walls. 

Small works such as replacing the windows don't normally require permission however there are some instances that may do, such as if you live in a listed building or a conservation area. 

We recommend that you check on your local authority website for any restrictions.

What about building regulations?

Even though you may not require planning permission, you always need to ensure that your internal renovation is fully compliant with building regulations. This is to ensure your extension meets health and safety requirements.

Building regulations checks will include:

  • The new structure including supporting walls
  • The fire resistance
  • The insulation and ventilation

If you hire a trades-person who is registered under the competent person scheme then they will self certify their work complies with the Building Regulations instead of having to submit a building notice. Many kinds of work can be self certified such as replacing windows or replacing the boiler.


If the work being carried out can't be self-certified then a structural engineer can prepare the drawings for building regulations approval. They will often submit the building regulation plans for you but do make sure they are covering this off. The site will be inspected to confirm the extension has passed. You should get a completion certificate 8 weeks after completion - do make sure you get this.

For more information, read our article your guide - building regulations.


Are there any other certificates I should look out for?

If you are having any electrical installations or alterations, then you should be issued with an Electrical Installation Certificate (EIC) which provides you with a declaration that the installation, alteration or addition was safe to use at the time it was put to service.

If you are hiring a gas engineer, make sure they are on the gas safe register and that they register the installation of a gas heat producing appliance with building regulations.

For all self certifying any work (such as replacing windows), make sure you have the paperwork and your trades-person registers it with the relevant body.

Who will be involved?


1. Architect

If you are simply redecorating or fitting a new kitchen or new bathroom then you don't need to pay for an architect. Or if you have a clear idea on your new layout then you won't need the design help of an architect.

However, if you need help with a new layout then a qualified architect (RIBA) can help kick off your project. An architect (RIBA) is the best route if you need design inspiration on your internal renovation. This can be extremely useful if you need help with the flow of your home and make it work better. 


2. Structural Engineer

A structural engineer will be responsible for producing the structural drawings and calculations that are required for building regulations. Unless the work can be self certified by your builder, structural engineers will be involved in your renovation. 

If you have a clear design brief then an experienced structural engineer may be the only contact you need apart from your builder.


3. Surveyor

If you are carrying a large renovation on a run down property it is worthwhile appointing a surveyor at the outset to identify any issues that you may otherwise overlook. A surveyor will also be able to help with other issues including the Party Wall Act (England and Wales only).


4. Builder

Unless you are an expert yourself then you will need to appoint a builder. You can either choose a builder who can do everything and employs specialists (such as plumbers and electricians) or you can employ individuals and project manage the process. 

Be aware that project managing various tradesmen that haven’t previously worked together might be challenging.

Read our article how to choose the best builder for your renovation if you need more help!


How much will it cost to renovate my home?

Anything from several thousands for a new bathroom to in excess of £100,000 if you are remodelling your entire home. Make sure you budget accordingly and the investment in your property is worthwhile. Knocking down supporting walls and changing the internal layout can be costly so draw up a detailed budget before you begin!



Published: May 25, 2018

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