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A Guide To Attic Conversion Costs

If you're looking to increase the value of your home for sale or looking to increase your living space without lengthy and costly planning permission delays, there are few better options than an attic conversion. Turning the unused space in your home into a whole new living area can revitalise a house and increase the sell-on value by an average of 15-20%.

There are a lot of possibilities to consider when planning your attic conversion and the costs involved are highly variable. That's why we've put together this handy guide on what you can expect to pay, based on the type of conversion and the size of the project.

4 August 2020
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Eugene Kim

Table of Contents

Types Of Attic Conversion

Different styles of loft conversion London require different levels of work to the property and have a big impact on cost. Let’s have a look at the different options from the cheapest to the most advanced.

Velux Conversion

A velux conversion, or skylight conversion, is the cheapest form of attic conversion as it uses the existing shape of the roof. You can think of this as essentially adding windows, a floor, and stairs to your existing attic. Typical costs range from as low as £13,000 up to £27,000. In terms of space, this would work out to roughly £1000 – £1300 per square metre (plus VAT).

For those who are looking to convert their current home, it’s also worth noting that a Velux conversion will cause the least disruption and generally be quicker to complete than other projects, taking around 4-6 weeks on average.

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Dormer Conversion

A dormer attic conversion offers different configurations for the shape of the finished room, meaning that costs are more variable depending on the project. Dormer conversions build out the existing roof, creating more space in the room and giving the property a different look. Typical options include L-shaped, gable-fronted, small and full conversions.

Dormer attic conversion costs can range from £23,000 to £37,000 for an average project or up to £52,000 for a larger London based conversion. Due to the increased space offered by a dormer conversion, per square metre costs stay relatively reasonable at around £1100 to £1400.

Hip To Gable Conversion

A hip to gable conversion extends the roofline of a sloping roof so it is in line with the edge of the property. This creates a lot of extra space but only works on sloping roofs. Detached properties with sloping roofs can extend both sides to create an even larger space. Hip to gable conversions cost around £28,000 to £37,000 on average. Similar in scope to a dormer conversion, these projects take typically around 6-8 weeks to complete.

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Mansard Roof Conversion

The most advanced type of conversion, a Mansard roof conversion essentially rebuilds the top floor of the home, offering vastly increased space and customisable design. These conversions involve the most work, costing on average £40,000 to £45,000 and taking around 8-10 weeks to complete.

To find out more about attic conversion costs, contact expert architects in London at Extension Architecture now.

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Eugene Kim

Eugene Kim, Founder and Managing Director of Extension Architecture, has led the firm for over 14 years, consistently delivering quality solutions. His dedication has been key to the company's growth and success.

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