How Much Does A Loft Conversion Cost?

Understanding the costs of a loft conversion in 2024

Are you considering a loft conversion to create extra space in your home? It’s an exciting project that can add significant value and functionality to your property. However, one of the most pressing questions on your mind is likely, “How much will it cost?”

On average, a typical UK loft conversion will cost around £50,000. However, this price tag can vary considerably depending on the size and complexity of the project. It should take approximately 6-10 weeks to complete from the start of the construction, once you’ve obtained any necessary planning permits.

Average cost of loft conversion The size and type of loft conversion you choose are the two most influential factors that will affect the final cost. Based on a 30m2 loft space: 

  • A Velux loft conversion will cost £22,500 – £30,000.
  • A shell loft conversion will be around £22,500 – £37,500.
  • A dormer loft conversion is more expensive and will cost in the region of £40,000 – £60,000.
  • At the more expensive end are hip-to-gable loft conversions, which will cost £50,000 – £70,000 on average.
  • Mansard loft conversion, costing about £50,000 – £80,000.
  • For a bungalow loft conversion of 50m2, you’ll be looking at a cost of around £62,500 – £87,500.

How much is a loft conversion in 2024

1. Initial Considerations

Before delving into specific costs, it’s essential to consider various factors that can influence the overall expense of your loft conversion:


The type of loft conversion you choose (e.g., dormer, hip-to-gable, mansard, or Velux) will significantly impact costs.


The size and complexity of your loft space, as well as any structural modifications required, will affect the overall cost.


The quality of materials and finishes you select will also play a role in determining the final expense.

2. Breakdown of Costs

While exact costs can vary depending on your location and specific requirements, here’s a general breakdown of the expenses involved in a loft conversion in the UK:


This includes architect fees, planning permission (if required), and building regulation approval. Expect to pay anywhere from £1,500 to £3,000 for this stage.


This involves reinforcing the floor, adding structural beams, and ensuring the loft can support the additional weight. Structural work typically ranges from £15,000 to £20,000.


Installing windows (such as Velux roof windows) and modifying the roof structure can cost between £3,000 to £6,000.


Proper insulation is crucial for energy efficiency. Budget around £1,000 to £2,000 for insulation, and consider additional costs for heating installation.


Wiring, lighting, and plumbing will need to be installed or modified to accommodate the new space. Budget £2,000 to £4,000 for these services.


This includes plastering, painting, flooring, and any additional interior features. Costs can vary widely depending on your preferences but typically range from £5,000 to £10,000.


The location of the property also plays a role in determining loft conversion costs. Labour rates, material prices, and accessibility to skilled professionals can vary depending on the region, influencing overall project expenses.

3. Additional Considerations


It’s wise to set aside a contingency fund of around 10% to 15% of your total budget to cover any unexpected expenses or changes during the project.


Remember to factor in Value Added Tax (VAT), which is currently set at 20% for most building work in the UK.

4. Conclusion

Loft conversion costs in the UK can vary widely depending on factors such as the type of conversion, size, complexity, location, and desired finishes. While it’s essential to set a realistic budget and explore cost-saving options where possible, compromising on quality or safety is not advisable. Consulting with experienced designers and builders can help homeowners accurately estimate costs and navigate the complexities of loft conversion projects.

While loft conversion costs can seem daunting, they are ultimately an investment in your home’s future. By carefully planning and budgeting for each stage of the project, you can create a beautiful, functional space that adds value to your property and enhances your quality of life.

Loft Conversion

Do I need planning permission for a loft conversion?

Not necessarily. In most cases, a straightforward loft conversion is considered ‘Permitted Development’, which means it shouldn’t need planning permission. That said, if you’re planning on extending beyond the specified conditions of Permitted Development, you live in a conservation area, or you have a listed property, then you will need to apply for planning permission. Also, if you’re planning to alter the shape or height of your roof structure then you’ll also need planning permission.

That includes any windows or structural changes that will sit outside of the current dimensions of your roof. To ensure your loft conversion project complies with all permissions and regulations, we recommend always checking with your local planning office before you begin the project.

Interior of a house, loft conversion bedroom seen across stair banister
Interior of a house, loft conversion bedroom seen across stair banister

Loft conversion building planning regulations loft conversions will need official building regulations approval

That means you need to get a registered building control surveyor to inspect your conversion at various stages of the project. They will also issue you a completion certificate following a final inspection once the conversion is complete. If you live in a semi-detached or terraced property, you’ll need to notify your neighbours before you start any planned building work under the requirements of the Party Wall Act 1996.

Loft conversion

Useful loft conversion checklist:

 ·       Plan, plan, plan. Loft conversions can be complicated, so it’s important to be in control throughout the whole project.

·       Calculate your budget as a starting point and plan from there. Remember to include all potential additional costs.

·       Factor in contingency for changes and extra costs during the conversion.

·       Decide what you need the space for and research your options. Contact your local planning office to confirm if you’ll need planning permission or not.

·       When hiring a professional always choose registered competent tradespeople with qualifications and accreditations such as the Chartered Institute of Architectural Technologists and Federation of Master Builders such as us.

To find out more please book a free consultation. We would be happy to help!



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