Loft Conversion Cost UK – Planning to undergo loft conversion to gain more space? Then keep reading this comprehensive guide that’ll address all your concerns related to loft conversion costs. In the urban landscape, loft conversions serve as an ultimate option for extending the home to increase the habitable area. Having a sound knowledge about the prices will help you strike a better deal. Also, knowing cost estimates will keep you rest assured that you’re paying the right money and you’re not cheated. Here we have covered every loft conversion cost aspect in detail along with loft conversion type. So, without further ado, let’s get started.
The average cost of loft conversion for a basic 20 m2 will be around £20,000 and for a bigger and more luxurious one, it comes out to be around £50,000. This is just a cost estimate, the actual cost will depend on the type of loft conversion availed and its complexity. Other main factors that may affect loft conversions costs are:
It may take around 6 to 8 weeks to complete the loft conversion construction. The construction process kick-starts once all the planning permits or other formalities are completed.
| Size of Loft Conversion (m2) | Average Cost |
| 20 | £20,000 |
| 30 | £25,000 |
| 96 | £40,000 |
The average cost of a Velux loft conversion will be less than that of a dormer and mansard. The reason is that lesser complexity is involved. In some cases, where the space is larger, Velux loft conversion would be like doing the walls, flooring, and insulating only and the area would be ready. The average cost of a Velux loft conversion starts from between £15,000 and for a small dormer loft conversion, the cost will start from £20,000 and upwards. While a hip-to-gable loft conversion that transforms a hip roof to a gable end starts from around £30,000. Mansard loft conversion is the most expensive as it reshapes the entire roof and is more like adding a storey. The average cost of Mansard loft conversion starts from £40,000 and can go up to £70,000 depending on the features you add.
| Type of Conversion | Average Cost per m2 | Average Cost |
| Velux | £1,000 | £15,000 |
| Dormer | £1,500 | £20,000 |
| Hip-to-gable | £1,200 | £30,000 |
| Mansard | £1,800 | £40,000 |
The costs stated above are just estimates.
There are multiple types of loft conversions, and each has its own benefits. Indeed, there are cost considerations as well. Adding more windows, luxurious finishes, a new staircase, installing a bathroom etc will certainly increase the cost of the loft conversion. Apart from that, there are certain factors such as the location of the project and weather conditions that also impact the cost. Unfavourable conditions adversely affect the time to completion and cost as well. Let us dig down on each type of loft conversion option and understand the detailed costs.
(A) Cost of Velux Loft Conversion: Also known as skylight or roof light loft conversion, Velux loft conversion is the simplest and most cost-effective loft conversion. Here skylights or roof light windows are added to the pitched roof. The cost varies depending on the number of windows installed, the size of the attic, flooring, insulating or other features. The average cost for a 20m2 area for Velux loft conversion is estimated to be between £15,000 and £25,000. Here is a breakdown of the expenses and services. The entire process takes around four-six weeks for completion.
| Cost Breakup | Price |
| Average Total Cost | £15,000 to £25,000 |
| Builder cost | £10,000 to £20,000 |
| Structural Engineer | £500 to £900 |
| Architect | £1,100 to £1,700 |
| Plumber/Electrician | £1,000 to £1,800 |
| Other professionals Fees | £500 to £700 |
(B) Cost of Dormer Loft Conversion: Dormer loft conversion is one of the most popular and preferred types of loft conversion in London. Here you get more headroom as the roof is extended vertically and a box structure is added to provide that extra space. There are many types of dormer loft conversion available in the market such as L-shaped, gable-fronted, flat-roof dormers, hipped roofs and more. Each has its own implications. The average cost of a dormer loft conversion starts from £20,000. It keeps on increasing according to size, complexity or if any structural modifications are required.
| Cost Breakup | Price |
| Average Total Cost | £20,000 to £38,000 |
| Builder cost | £12,000 to £24,000 |
| Structural Engineer | £600 to £1,100 |
| Architect | £1,500 to £2,500 |
| Plumber/Electrician | £2,000 to £3,000 |
| Other professionals Fees | £700 to £1,500 |
(C) Cost of Hip-to-Gable Loft Conversion: Hip-to-gable loft conversion involves converting a hipped roof to a gable wall. This provides more internal habitable space. The new space can easily be used to create a bedroom, a kid’s room or even a gym space. Hip to Gable loft conversion is ideal for properties having a hipped roof or terraced houses. The average cost for a 20 metres square hip to Gable loft conversion starts from £30,000. The final price may vary and depends upon various factors such as structural work required, size of the loft, complexity of the project and additional features.
| Cost Breakup | Price |
| Average Total Cost | £25,000 to £45,000 |
| Builder cost | £15,000 to £30,000 |
| Structural Engineer | £700 to £1,500 |
| Architect | £1,700 to £3,000 |
| Plumber/Electrician | £2,200 to £4,000 |
| Other professionals Fees | £1,000 to £2,000 |
(D) Cost of Mansard Loft Conversion: Mansard loft conversion is one of the most expensive ones as it involves altering the entire shape of your roof. A mansard roof provides you with the maximum internal space. As it involves a complex design and extensive structural alterations, the cost touches £40,000 to £70,000 with an average of £50,000 for a normal-looking mansard conversion.
| Cost Breakup | Price |
| Average Total Cost | £40,000 to £70,000 |
| Builder cost | £25,000 to £40,000 |
| Structural Engineer | £600 to £2,000 |
| Architect | £1,700 to £3,500 |
| Plumber/Electrician | £2,000 to £3,000 |
| Other professionals Fees | £700 to £1,500 |
(E) Cost of Bungalow Loft Conversion: The best way to expand and add additional space to a bungalow is by converting its loft into a habitable space. You can easily go for any type of Bungalow loft conversion that includes Velux, dormer, or mansard loft conversion. The basic cost of a bungalow loft conversion starts from £25,000 and may go up to £50,000 depending on structural requirements, property design, size of attic and type of conversion.
| Cost Breakup | Price |
| Average Total Cost | £25,000 to £50,000 |
| Builder cost | £15,000 to £30,000 |
| Structural Engineer | £700 to £1,500 |
| Architect | £1,500 to £3,500 |
| Plumber/Electrician | £2,000 to £3,000 |
| Other professionals Fees | £1,000 to £1,500 |
Loft conversion involves a lot of trades and building processes as part of construction. To get a perfect cost loft conversion idea, here is an entire cost breakdown for a loft space 30m2 for a dormer loft conversion. The space includes a dormer, and a Velux window over a new staircase. A new bedroom with ensuite is constructed with full plumbing and electrical work. Here’s the estimated cost breakdown.
| Job/ Process for Loft Conversion | Cost (for 30m2 loft) |
| Project Management – including building control costs | £9,000 |
| Internal Preparation | £1,000 |
| Roof Coverings | £6,200 |
| Alterations to Roof Structure | £4,200 |
| Steelwork to support structural changes | £3,400 |
| Joinery – excluding staircase | £3,600 |
| Electrics | £1,000 |
| Plastering | £2,400 |
| Staircase | £2,200 |
| Decoration | £1,000 |
| Total | £40,000 |
As such there is no fixed cost calculator for loft conversion, there are several factors associated with this. Let’s discuss some of the above-mentioned trades in detail.
Many other costs may be omitted by the contractor or builder such as the cost of supplying the fixtures/materials, VAT charges, decorations, Juliet balconies etc. Just be open with your loft conversion contractor about these charges. Stay vigilant before making any final decision. Apart from these, there may be certain hidden or unknown charges that may apply. These include:
Certain other factors impact the cost of the loft conversion. Have a look at them:
Let’s discuss some tips and strategies to reduce the loft conversion costs.
Loft conversion is one of the best investments of your life that will not only add habitable space but also increase the value of your property. As it is a big project you need to hire a reliable and trustworthy contractor that has a rich and diverse experience in loft conversion. TEL Constructions is one of the leading loft conversion companies in London that has converted countless lofts to multiple types of houses. Be it detached, semi-detached or terraced, speak to us regarding your choices, tastes, and concerns. Our team will happily assist and guide you through our loft conversion journey.
A professionally built loft conversion will add approximately 20% – 25% value to your existing property. Other factors that may impact property value are location, current market condition and quality of construction.
Velux loft conversion involves minimum structural changes to the loft, and you just need to perform the basic works such as installing windows, staircase, insulation, heating, decoration and plastering. This way Velux loft conversion offers the cheapest way.
Want to build a new home or renovate your property? Oh!! You are on the right platform. Just submit your details here and schedule a free visit of our experts today.
join our private members list today and get updates of special offers & new products !
