Loft Conversion Or Extension – All You Need To Know | Checkatrade
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Loft conversion or extension?

If you’re looking to create more living space in your home, and are contemplating a loft conversion or extension then this article is for you. When it comes to making the decision, you want to make sure the solution for more living space is the right fit for you and your home – whether you decide on an extension or loft conversion.

If you’re looking to create more living space in your home, and are contemplating a loft conversion or extension then this article is for you. When it comes to making the decision, you need to make sure that the solution you choose for more living space is the right fit for you and your home.

In this guide, we highlight the differences between a loft conversion and an extension, including which is cheaper and which adds more value to your home.

Top 4 tips for choosing an extension or loft conversion

When you’re trying to weigh up the options of an extension or loft conversion, there are a number of key factors you’ll want to consider to help you make the decision.

1. Be clear about what the space is for

One of the first things you need to be clear on is what you’re planning to use your loft conversion or extension for. If you need an additional bedroom, then a loft conversion is a great option. But, if you’re looking for more general living space for day-to-day use then a general extension is more often a more suitable choice.

2. Consider the disruption

Large loft conversion bedroom with en suite bathroomA big home improvement job, like an extension or loft conversion, will inadvertently cause some disruption in your home – but not to the same degree. A big rear extension, for example, might mean a big chunk of your house needs to be vacated during the construction. And, in some cases, you might have to move out of your house altogether. With a loft conversion, the disruption is generally a lot more manageable.

3. Figure out the costs

One key factor in your decision will be your budget. To understand how much your extension or loft conversion project is going to cost, speak to a local architect or designer who’s carried out similar projects before. They should be able to give you a rough idea of costs and timelines, as well as an idea of any planning permission or building regulations you’ll need to consider.

4. Find out what value you’ll add

If you want to make sure you’re making a good investment in upgrading your home, instead of moving to a larger property, you’ll want to find out how much value you’ll be adding with your extension or loft conversion. Start by speaking with a reputable local estate agent or surveyor and getting them to assess your planned project to see what value-add they estimate. Take a look at our guide to see how much value a loft conversion could add to your home and how much value an extension could add to your home.

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What is cheaper… a loft conversion or an extension?

One of the key questions we get asked all the time: is a loft conversion cheaper than an extension? And the answer is… it depends. Helpful, right? Don’t worry, we’re not going to leave you hanging. The average house extension cost in the UK ranges from around £25,000 – £112,500, while the average loft conversion cost ranges from about £27,500 – £75,000. 

Side house extension with kitchen

From those figures, you can see that there’s a big range for the cost. The total price you pay will come down to the size, shape and complexity of the design for the space you’re building, as well as the standard of finish you go for.

Want to know more about costs? Check out our range of useful cost guides to help you plan your budget:

What adds more value, an extension or loft conversion?

Depending on the size and scope of your project, both extensions and loft conversions have the potential for adding up to 15-20% to the value of your property. The exact increase in value will depend on the specification, quality of finish and type of living space that’s been added to your home.

Adding bedrooms and bathrooms tend to be the highest earners in terms of adding value. That said, if you’re adding bedrooms you also need to make sure the living space in your home is sufficient for the number of people living in the property.


Is a loft conversion classed as an extension?

As long as your loft conversion isn’t altering the dimensions of your property’s existing roof space, then it won’t be classed as an extension. And, as such, you won’t need to worry about planning permission for your loft conversion as it will be covered under permitted development rights – as long as the new loft space is not more than 40m3 for a terrace, or 50m3 for a detached house.

Is it worth getting a loft conversion?

Loft conversions are increasingly popular with British homeowners looking for added space at home for a number of reasons. Depending on what you’re looking to achieve, here are some of the main benefits of a loft conversion:

    • Increase the value of your home by up to 20%
  • Make use of dead space in the roof
  • Cheaper per square metre than a house extension
  • No need for planning permission (as long as you adhere to permitted development rules)
  • Loft conversions can often improve a home’s energy efficiency and reduce energy bills

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