Adding space your home: Loft conversion or extension?

Adding space your home: Loft conversion or extension?

With 2019 now up and running, you may be considering adding space to your home.

Certainly it can pay off for those willing to undertake work. And more and more people are now opting to add additional space to their properties rather than move.

But where do you start? And which is better, extending your home or undertaking a loft conversion?

We've compiled everything you need to know and looked at the pros and cons of both extensions and loft conversions...


The first thing to consider before looking at an extension is whether you can add value to your home by undertaking the work.

The best place to start can be your local estate agent. They will know about other similar projects in other properties in your area and should be able to advise on how much added value your own extension could net you.

That can help with budgeting your project and, most importantly, deciding whether it is the right option for you or whether you would be better moving home to get the space you need.

If you are set on an extension, think about how best to use the space to meet your needs, as well as add value.


Planning permission is the main thing that can strike fear into someone considering a home extension.

And it's true: Obtaining planning permission and the process itself can be testing.

But did you know you can undertake some work without needing planning permission.

Under 'Permitted Development', you can provide a three-metre deep single-storey rear extension for an attached (i.e. terraced or semi-detached) property or a four-metre deep single-storey rear extension for a detached property. You can also provide a three-metre deep two-storey rear extension for a property, providing it meets additional criteria.

There are also height rules for permitted development extensions. In order to be certain what you can and can't do, it's best to do some more in-depth research or speak with your local authority's planning department.


This will depend on lots of factors, including:

  *  How much space you want to add

  *  The standard of finish you require

  *  Whether you decide to use an architect

The average cost of an extension in the UK is £1,500 per square metre, which is doubled for a two-storey extension.

Use of an architect can ease the strain of completing a larger extension, perhaps to house a striking kitchen/dining room. But architect fees can hit your pocket, so it's important to stick to your budget.

The next step is to look for tradespeople to carry out the work. Try to get at least five quotes from recommended builders and consider everything from their approach to your project and availability as well as the price. The cheapest might seem appealing, but it is not always the best option.


  *  More flexibility than a loft conversion

  *  Better design space

  *  Less disruption than a loft conversion


  *  Planning permission may be required

  *  More costly than loft conversions


Like extensions, loft conversions can add significant value to your home as well as the space you desire.

With costs associated with moving remaining high, many people opt to add space to their current homes rather than go through the process of moving.

But it's important to consider your needs and aims before undertaking a loft conversion.

If you want to go ahead, you'll need to assess your loft space to see if it is suitable for conversion. Most roof spaces are, but you should call in a trusted tradesperson to measure your loft's internal height, roof pitch and footprint.

Think about how best to use the space. Perhaps a bedroom and en-suite or home office space? Or maybe that dream home cinema!


One of the best things about loft conversions is most do not require planning permission. However, if you are looking to extend the roof space you may require permission.

It's always best to check with your local authority planning department before undertaking any work or committing to architects or builders.


As with an extension, much of the cost will depend on the space you wish to create and how you want to use it.

The average cost of a loft conversion (double bedroom and en suite) in the UK is £35,000.

Use of an architect could be an un-required additional spend given the space in your loft already exists, but architects can often squeeze every last inch of space from a loft conversion with clever design so are worth considering.

Like an extension, your biggest spend will be on a builder to undertake the work, so take your time and glean at least five quotes from trusted local tradespeople.

Weigh up what you want to achieve from your loft conversion against your maximum budget.


  *  Often don't require planning permission

  *  Quicker completion time than extension

  *  Usually less costly than an extension


  *  Dependent on existing loft space

  *  Sloped roof limits use of space

  *  Harder to achieve natural light requirements

  *  More disruption than an extension


Whether you opt for an extension or loft conversion, your project must comply with building regulations.

Ensure any tradespeople you use are able to certify their work via official trade bodies such as FENSA (windows) and Gas Safe (gas).

If they aren't, they must be able to liaise with the local authority to have their work signed off.

Failure to comply with building regulations could mean you have to take down your extension or revert your loft conversion and could affect your ability to sell your home in the future.


Building work is one of the biggest causes of neighbour disputes.

Even if you know your neighbours will be made aware of your plans to extend by the local authority planning department, it is often best to make them aware yourself in advance.


This refers to a shared wall, often between two semi-detached homes or terraced properties. However, it also includes garden walls across property boundaries.

If your extension project requires excavations and ground work close to a neighbour's property, you may require a party wall agreement. This could also be the case for a loft conversion in a semi-detached or terraced home requiring steel supports.

If you're thinking of adding space to your home but are unsure of the value it will add, get in touch with Martin & Co Camberley and one of our property experts will be able to help with advice and guidance.