How much does a loft conversion cost?

Cost of loft conversion full guide

Dreaming of extra living space in your home? A loft conversion might be the perfect solution! Discover how a loft conversion can increase your property's value and livability.

Curious about costs? Read on to learn about the average price and what affects loft conversion prices.

In this Price Guide we will talk about:

1. Average cost of converting a loft
2. The cost of hiring a loft conversion company
3. Different types of loft conversion and costs
4. Loft flooring and insulation costs
5. Loft conversion planning permission costs
6. Find loft conversion companies fast on MyBuilder
7. FAQ: Common questions about loft conversion costs

Average cost of converting a loft

Dreaming of more space without the hassle of moving house? A loft conversion is a brilliant, popular choice for homeowners wanting to maximise their home.

But how much does an attic conversion cost in the UK?

Here's a table of common loft conversion types and their average costs:

Type of loft conversion	Average cost range
Velux loft conversion	£22,500 to £30,000
Dormer loft conversion	£40,000 to £60,000
Hip to gable loft conversion	£50,000 to £70,000
Mansard loft conversion	£50,000 to £80,000
Modular loft conversion	£50,000

The cost of hiring a loft conversion company

Choosing the right loft conversion company turns your dream attic into reality by providing the full service.

Hiring a full-service loft conversion company is easier than managing separate architects, builders, and electricians yourself. They coordinate everything seamlessly for a stress-free project.

• Cost breakdown of a loft conversion company:

• Labour & management: 40-50% of the final cost (£15k–£30k)

• Materials: 30-40% of the final cost (£10k–£25k)

• Extras (architects, scaffolding): £800–£2,500+ ​

To get an even better idea of how much hiring a loft conversion company may cost you, it’s so simple to post your job on MyBuilder today.

Just add a couple of sentences all about your attic conversion, and then loft conversion companies in your area will reach out. It’s as simple as that.

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Different types of loft conversion and costs

Loft conversions come in various types to suit different home layouts and budgets, each offering unique space and style benefits.

Choosing the right one depends on your roof shape, property type, and desired headroom, with loft conversion costs varying widely in the UK.

Velux loft conversion costs (£22,500–£30,000 average):

Adds roof windows for light and ventilation without altering the roofline - perfect for smaller attics needing simple, budget-friendly space boosts while keeping that classic look

Dormer Loft Conversion costs (£40,000–£60,000 average):

Builds box-like extensions from the roof for headroom and floor space, ideal for larger bedrooms or offices with good views.

Hip to gable loft conversion (£50,000–£70,000 average cost):

Change your sloped roof to straight walls for loads more space. Perfect for end-terrace or semi-detached houses wanting a big upgrade.

Mansard Loft Conversion costs (£50,000–£80,000 average:

A steep, curved roof design for premium head height across the whole space, often used for luxury conversions blending style and functionality.

If you’re not sure about what loft conversion will best suit your house, it’s easy to find verified loft converters on MyBuilder. Just upload a photo of your home, or desired loft conversion, and they will be ready to help!

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Loft flooring and insulation costs

Picking the perfect flooring and insulation for your loft conversion makes all the difference for cosy comfort and lower energy bills.

Cost of attic flooring

Whether you’re hiring a flooring fitter, or installing it yourself, flooring can make a massive difference to your loft conversion.

Here’s what you can expect to pay when choosing flooring for your loft conversion:

Type of Flooring	Average Cost per m²
Vinyl	£15 to £25 per m²
Wood	£20 to £85 per m²
Carpet	£10 to £65 per m²
Tiled	£50 to £100 per m²

MyBuilder: Considering carpet for your loft conversion flooring? Visit our price guide for all carpet fitting costs.

Cost of attic insulation

It’s vital that your loft conversion is properly insulated against the elements. There are several different options when choosing insulation.

Sheet Insulation: Rigid panels for easy install.

Loose-Fill Insulation: Tiny particles fill gaps perfectly for top coverage.

Blanket Insulation: Flexible fibres that adapt to spaces.

MyBuilder Tip: For more insulation costs, visit our price guide.

Loft conversion planning permission costs

Costs associated with obtaining planning permissions and adhering to regulations can vary.

For some loft conversions, planning permissions might be required, adding up to £1,000 to the project's budget.

MyBuilder Tip: Consult with a building professional early in the planning phase to determine whether your loft conversion will require approval and to anticipate associated costs.

Find loft conversion companies fast on MyBuilder

Posting your job on MyBuilder only takes a couple of minutes, and then professional loft conversion companies in your area can respond. It’s the quick and easy way to request quotes, compare companies, and find the right conversion company for you.

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FAQ: Common Questions Readers Ask About Loft Conversions

What steps are involved in the loft conversion process?

A loft conversion typically involves several key steps to transform your attic space into a functional room.

1. Obtain planning permission or check if your project falls under permitted development rights.
2. Engage a structural engineer to assess whether your loft can support the conversion.
3. Hire an architect or designer to create detailed plans.
4. Reinforce the floor, install windows or dormers for natural light, and construct walls and ceilings.
5. Install plumbing and electrical systems if required.
6. Insulate the space, apply plaster and complete the interior fit-out.
7. Schedule a building regulation inspection to ensure compliance with safety standards.

Are there any cost-effective ways to reduce the price of a loft conversion?

There are several strategies to make a loft conversion more cost-effective. Opting for a dormer loft conversion instead of a more complex Mansard conversion can significantly reduce costs, as it involves less structural alteration. Retaining the existing roof structure and minimising changes to plumbing can also save money.

Are there any extra costs in loft conversions?

Hidden costs can add 10-20% to your loft conversion cost, catching many homeowners off guard. Common surprises include planning permissions (£300–£1,000+), structural engineering checks (£500–£1,500), and scaffolding (£1,000–£3,000).

How long does a loft conversion take?

Most UK loft conversions take 8-12 weeks once work begins, depending on the type and complexity. Velux projects wrap up in 6 - 8 weeks, while dormer or hip-to-gable styles stretch to 10 - 14 weeks due to roof changes.

How will a loft conversion change the value of my property?

A quality loft conversion boosts UK property values by 15-25%, adding £40,000 - £80,000 based on location and finishes. You can often recoup 60 - 80% of the average cost of converting a loft through higher sale prices, especially in London.