A proper loft conversion: The costs and right professionals

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A proper loft conversion: The costs and right professionals

Johannes van Graan Johannes van Graan
Loft Conversion and Kitchen Renovation:  Detached home by Resi Architects in London,
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In need of some extra space in your home? Ever considered building up instead of out? In many cases, a loft is a far better option than an extension, particularly when your garden / yard size won’t accommodate an add-on structure.

But of course, like all things in life, decent planning is key to ensure proper results, and that includes budgeting. But before we take a look at some ballpark figures for loft conversions, let’s highlight one UK professional team that’s quite seasoned when it comes to lofts: Resi.

Combining technology and human engineering skills to become the UK’s first online architectural service, Resi ensures affordable design solutions for anyone considering a brand-new house, an extension, or a loft conversion. They aim to make it easier than ever for everyday homeowners to transform their property, with a clear step-by-step process that gets anyone, no matter the size or budget, ready to build with confidence. 

A range of services can be counted on when choosing Resi for your project, including home design, 3D rendering, measured surveys, and help managing both planning permission and building regulations. They'll even introduce you to the best contractors / suppliers in your area, so you're in safe hands for the rest of your project. 

1. The cost of an average loft conversion

Various factors will affect the cost of your loft conversion, including your roof structure and whether or not you require alterations to accommodate a staircase. 

For the cheapest option, consider a basic ‘room in roof’ loft design, which could start around £15,000. The following are usually included: 

• A reinforced floor

• Skylights

• Additional insulation

• A staircase

• Electrical work, lighting and heating

• Fire safety measures (like fire doors and smoke alarms) to comply with Building Regulations.


2. A dormer loft extension

Including all of the previously named elements, this loft extension also has dormer windows. This ensures extra useable floor space and more head height, giving you more options when it comes to staircase placement. 

The cost of such a design can start around £20,000. But if you plan on having a dormer loft conversion with a double bedroom and en-suite bathroom, the costs can push up to £35,000–£45,000.


3. Changing your roof

Outside View of the Kitchen Extension:  Terrace house by Resi Architects in London,
Resi Architects in London

Outside View of the Kitchen Extension

Resi Architects in London

The most costly option, as this type of conversion requires the removal and rebuilding of your house’s roof. A designer will need to be hired, and this type of project requires Planning Permission, too. 

It’s likely to cost upwards of £40,000.

4. The different types of loft conversions

Exterior of this London home:  Detached home by Resi Architects in London,
Resi Architects in London

Exterior of this London home

Resi Architects in London

• Velux: Generally the most affordable option which involves adding a window or two into the roof for more light – about £21,000-£41,000.

• Dormer: The most popular type of loft conversion in the UK, which is a small flat-roofed extension with a window – from around £31,000-£58,000 for a standard dormer and approximately £40,000-£60,000 for an L-shaped design.

• Hip to gable: This is when either one or both of the end sloping parts of the house’s roof are replaced with a gable wall – usually £42.000-£65,000.

• Mansard: A very costly option, which involves replacing one entire side of the roof to make a straight wall and flat roof. It could also mean extending both sides to make an entire new storey – costs around £45,000-£75,000.


5. The tradesmen required for a loft conversion

Exterior View of Garden and Kitchen Extension:  Terrace house by Resi Architects in London,
Resi Architects in London

Exterior View of Garden and Kitchen Extension

Resi Architects in London

To ensure proper results and a project that proceeds as smoothly as possible, various tradesmen will need to be part of your loft conversion project. These include:

• Builders to construct walls and determine what is structurally possible

• Glaziers to decide on the best type of windows

• Electricians

• Heating engineers

• Plumbers

• Joiners for the new ceiling joists and possibly bespoke storage solutions

• Plasterers to smoothen out the new walls

• Scaffolders for temporary roof support (if you choose hip to gable and mansard lofts)

• Painters (unless you opt for DIY decorations). 

Take a look at these Outstanding loft conversions for some inspiration!

Would you consider a loft conversion for your home?
Whitton Drive:  Terrace house by GK Architects Ltd,

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