You should contact a Structural Engineer for independent advice on extensions, loft conversions, outbuildings, through-lounges, removal of chimney breasts or basement extensions.

Here are some examples of what Structural Engineers do:

Extensions – The Structural Engineer will need to design foundations, roof timbers and openings into the main house. 

Loft conversions – The Structural Engineer will need to ensure that the new loft floor is well-supported, opening created to accommodate a new flight of stairs and design the structure for the rear dormer windows.

Outbuildings – The Structural Engineer will need to design foundations.

Basements – The Structural Engineer will need to design retaining walls and underpinning of existing walls.

Experienced Structural Engineers have worked with lots of different builders and contractors so they are very well positioned to make recommendations on good builders.

You have a number of options such as:

1. A rear extension to give you more space at the back of your house. Perhaps you need a bigger living area or could do with more space in the kitchen. These rooms are usually the heart of the home so any additional space is always welcome. 
2. A side extension to give you more room at the side of your house. This can only be done if you have sufficient space at the side of your house and you aren’t going to end up blocking a shared driveway or access point. 
3. Loft conversions – these can really transform a home and add a lot of value to your property, often adding two or even three rooms to a house. It is a popular option with growing families as it doesn’t impinge on the existing garden space.
4. Outbuildings – these are becoming increasingly popular with the advent of air bnb rental options and home working during the pandemic. 
5. Basement storeys – these are popular in more built up city locations but again can add value and added space to your home if done right. 

Before embarking on any project, clearly establish your objectives. 

If it is simply additional space you require, you will need to reassess how you use your existing rooms. 

If it is to add value to your property, it is best to consult a structural engineer as sometimes the cost of the build can outstrip any additional value when you go to sell the property.

Quotes for construction vary wildly. A structural engineer can help you to make sense of any quotes you are getting and advise you on what a reasonable ballpark figure looks like.

How do you know whether you need planning permission for work on your property?

This depends on whether your work is on a single family dwelling or a flat.

In single family dwelling houses there is the concept of ‘permitted development’ where some loft conversions and rear extensions can be built without planning permission.

(Permitted development rules may be waived for houses in conservation areas so always check with your local authority(council)).

For flats, these permitted development rules do not apply and planning permission will always be required.

Depends on the character of the chimney.

Most chimneys can be removed to provide additional space, but the manner in which this is done is important. You will need to be guided by your structural engineer.

In the past, there was a practice of using Gallows Brackets (brackets shaped like gallows) to support remaining chimney stacks.

This was found to be troublesome and more recently Gallows Brackets are frowned upon and engineers will always support chimney flus on steel beams.

In short: removing a chimney could devalue your property because structurally you’re removing support for the walls of the property. However, if carried out correctly, it can actually add value to your property due to the additional space created.

Step 1: Do I need permission?

First and foremost you should decide on your budget and whether or not the loft conversion can be carried out as a permitted development or whether you require planning permission. 

This can be done by contacting your local authority – your local council. Councils usually have a webpage about planning, a helpline you can call or email address you can contact to find this out.

Step 2: How much do I need to save?

As of 2021, you should budget on a cost of £1200-1500 per m2 of usable floor area.

The average loft conversion is between £30-50,000 depending on square meterage.

Step 3: Design of loft structure.

You will need to approach an independent structural engineer to design the loft structure and carry out the associated calculations.

Step 4: Choose your builder.

Always choose a builder with a record of previously completed loft conversions and try to see those before deciding. This can be more difficult in practice, so pictures of work and references or reviews are more achievable. Ensure you agree on the scope of work and timelines before giving your builder the go-ahead. Be sure to notify your neighbours that you will be carrying out works beforehand – they will appreciate the heads up and being notified of when your work will be completed.

If you own a semi-detached or terraced property, the walls between you and your neighbours are called party walls because they divide the two “parties” either side of the wall.

These days, if your neighbour applies to the local planning department to build a rear or side extension or loft conversion, an independent party wall surveyor may contact you by letter to make you aware of your rights. 

In reality, these surveyors are opportunists who look up the houses where construction work has been approved on council websites and then contact the person living next door to offer their services.

If you are on good terms with your neighbours, there may be no need to appoint a party wall surveyor, provided your neighbour agrees to make good any damage resulting from the building work.

You should talk to your neighbour’s structural engineer who will be able to explain the scope of work to you. Damage to the neighbour’s property is actually quite rare.

My advice would be to meet with your neighbour and take photos of the party wall before the works start and a couple of weeks after they finish. This is called a condition survey and should be conducted in the company of your neighbour to verify it’s veracity.