Many homes have a volume of unused space above the living area. These largely stays empty except for storing old suitcases and Christmas decorations. What a waste!
You might have a growing family or elderly parents that need looking after. If so, many householders choose to convert their loft into a living area or bedroom. This is a large investment and may need a lot of structural re-organising. But, the cost of a loft conversion is much less than building an extension or finding a larger house. Not only that, but the finished project will certainly add value to your property.
Converting your loft or attic into a new living space is so common that many building companies specialise in this type of work. They’ll take on the entire job, from working out an estimate, organising architectural plans and local authority approvals to building the conversion and giving the rooms a final lick of paint. However, you must remember that altering the timbers in a roof needs the input from a structural engineer to ensure that the roof doesn’t collapse. So, get the work done properly.
Loft conversion cost estimates
Before you start thinking about building, you’ll need an estimate of the approximate costs involved. Believe it or not, typical loft conversion prices vary hugely depending on the size of your property, what type of loft extension you require, the method of construction of your existing roof and many more factors.
- Type of loft conversion. There are many different types available and it’s up to you to find out which will be approved in your neighbourhood. Furthermore, you’ll want to know which types are feasible and come within your budget and which types you actually want. Probably, the simplest is called “Room in loft”. This just means that you build a room inside the existing boundaries of the loft. There are regulations in force that you must follow to build one of these. The most important involves the amount of available headroom. For example, there must be at least 2.2m between the ridge timber and the top of the ceiling joists. After this, it’s just a case of adding a staircase, strengthening floor joists, adding windows and insulation.
- Single storey conversions are the most common and easiest to build.
- Double-storey conversions might require improved house foundations because of the increased weight. Also, you’ll find that local authorities might not approve these as it’ll make the height of your home very different from those around you. Obviously, this is something they’re very strict about.
- Window style and roof shape will be at the discretion of the local authority and will vary depending on the area in which you live. Windows can vary from dormer style to roof light. Additionally, Roof shapes vary too, from a flat roof, mansard, hip and valley, gable and many more. Your architect will know which windows and roof styles are most likely to be approved.
- Loft conversion costs. We know that every loft conversion project is unique, so the only way to compare and contrast is to look at the costs per area (m2). The following table shows a typical cost per m2 for each project element and gives an idea of the percentage of the total project cost.
||Cost / m2
||% of the total project cost
|Site set-up and project management
|Strengthen floor joists
|Change roof structure
|Carpentry & joinery
- Average Price. It won’t come as a surprise that the typical loft extension costs vary depending on the style. Bear in mind that any of the following styles can be installed in bungalows and houses, so are worth considering no matter which type of home you have.
- A simple room in loft conversion usually ranges from £15,000 to $20,000.
- Dormer conversions are another cheap style for your home. They range in price between £30,000 and £60,000. However, the average is usually around £45,000.
- Hip to gable conversions are quite a complex structure and this is reflected in the price. They start around £40,000 and can reach £65,000. But, a typical average is about £55,000.
- Mansard loft conversions are extremely complex and might even require the existing roof to be replaced. Therefore, they are the most expensive option and range from £45,000 to £70,000. On average, a typical mansard will set you back around £60,000.
Remember that builders and loft conversion companies usually give their quotations without VAT, so make sure you understand whether this tax has been included or not. At the time of writing this article, the standard VAT rate is 20%, so you can see it significantly increases the price.
There’s another thing that will make the project more expensive, although this will be built into the quotation. Your geographical location in the country will alter the average amounts, with London and Home Counties being the most expensive.
Hiring professionals to plan and inspect the work is vitally important. An architect will be able to draw up suitable plans for submission to the local authority. Even if you don’t think you need permission, it’s worthwhile checking this out and discussing your plans with them. Furthermore, you’ll also need input from a structural engineer. This is because of the changes to supporting structural joists, rafters, and the increased weight on foundations when the conversion is complete.
- Your local authority has the responsibility of ensuring that your loft conversion doesn’t upset the local residents and complies with local planning regulations. The planning department always has the ultimate decision as to whether you can convert your home, and the methods used. There’s also usually a fee for submitting a planning application. The Planning Portal contains online calculator tools to help you calculate the costs but you must always notify your local authority in case special circumstances and different rates apply.
- The building control department of your local authority enforces the Building Regulations and ensures that the design, construction methods and materials of every building meets minimum standards. Some professional contractors, such as electricians, heating engineers and plumbers have special training. They can self certify their own work to be in accordance with the Building Regulations. Otherwise, you’ll need a Building Control inspector to check the work is up to the required standard. Building Control sets their own fees depending on how much work they have to do. So, contact their office to agree on a set price.
- If your conversion affects a shared wall with your neighbour (such as a terraced or semi-detached house), you’ll have to know about the Party Wall Act 1996. This statute prevents the structural integrity of neighbouring properties from being undermined by your building work. The cost of a Party Wall Notice will vary depending on the nature and complexity of the work. Consult an RICS accredited surveyor for an accurate quote.
Why you should consider converting your loft
So, let’s just review why we might need to convert our loft, shall we?
- Adds value to your home. You have an extra room, often with the same floor area as your house.
- It’s cost-effective. In most cases, the house’s structural foundations are perfectly adequate for the extra weight of a loft conversion. You, therefore, won’t need to dig down and underpin them. You also don’t normally need to build extra walls and you certainly won’t need to extend the footprint of your house.
- The conversion is flexible. You can add a loft conversion to most houses and make the extra room larger or smaller depending on your budget.
- Because the outside shell of your home is unaffected, adding a new loft conversion is relatively simple. Usually, the only breaks in the weatherproofing are to install windows and extend the roof. Everything else takes place indoors.
Adding a bathroom in a loft conversion
Many people use their new loft conversion as an extra bedroom. If you’re having the upheaval of building works in your loft, then it makes sense to include an en-suite bathroom and toilet into the project. If you decide on this extra work, you’ll have the additional tasks of supplying hot and cold water, ventilation and drainage to the new room. Additionally, you’ll connect these to the plumbing and drainage services serving the remainder of the house.
Adding an additional bathroom will increase the value of your property and make it more attractive to possible buyers in the future. Having said that, its also an added bonus for existing occupiers of the new bedroom. Using an en-suite is so much more convenient than having to walk downstairs to the family bathroom. You can have your own personal items set out as required and can use it whenever you want without disturbance by other family members.
Do loft conversions add value to a house?
Many surveys come to the conclusion that a loft conversion is the best way to add value to your home. The Nationwide Building Society has recently said that the work can increase the house value by 20% (source).
Do you need planning permission for a loft conversion?
If the loft conversion complies with certain conditions, it’s classed as a ‘permitted development’. In this case, the work doesn’t need planning permission. Having said that, it’s always worthwhile discussing your plans with the local authority to ensure you are within the law.
How about Building regulations?
Your new loft conversion must comply with the UK Building Regulations. The ‘approved documents’ provide guidance on how to comply. Specifically, the following sections refer to a loft conversion:
- Part B deals with fire safety in and around buildings. In the case of the loft conversion, this relates to the standard of fire retardance of materials, ventilation, fire detection and methods of escape.
- Part P deals with electrical safety. Basically, this states that you must use only recommended electrical fittings. It also specifies who is qualified to install electrical works and check the system before use.
- Fuel and power conservation require guidance as set out in Part L. This deals with insulation, heating, lighting, ventilation and air conditioning.
- Part K deals with protection from falling, collision, and impact. It includes guidance on windows, stairs, balusters and positioning of doors.
How long does a loft conversion take?
Loft conversion with a typical floor space of about 40m2, complying with all relevant Building Regulations will take about 11 weeks to complete. Smaller and simpler projects can take about 6 weeks. The duration will vary depending on the complexity of work, ease of access, and available manpower.
Get loft conversion quotes
From this article, you can see that a loft conversion is worth every penny spent on it. However, it isn’t something for the weekend DIY enthusiast to attempt. Not only do you need skilled and experienced professionals to do the work, but you also need someone who understands the building regulations and how they are applied.
It’s always worth requesting two or three different quotations from reputable building companies before you choose who’ll do the work. This isn’t always an easy job to do, as most people don’t know good builders from those trying to rip you off. On our website, all you do is simply complete a form and you’ll receive three quotes from experienced loft converters in your area. Then it’s up to you to follow them up.