How much do house extensions cost?
The home extension costs in this article are correct as of 2022
Building an extension is a popular way for families to get the most out of their homes, giving them extra space without having to move.
Extensions vary widely, so how much it costs to extend your home depends on a few key factors:
- The size of the extension
- The quality of the build and finishing elements
We’ve spoken to some of the世界杯2022赛程时间表最新 为了得到一个准确的价格指南的扩建工作，包括一个方便的房屋扩建成本计算器。以下是你需要知道的。
Home extension cost per square metre
Extensions are complex projects that encompass a variety of different elements and trades, from laying foundations and building walls, to plastering, electrics and plumbing - and that’s before getting to decoration, or features like adding a new kitchen.
A large variety of things can affect the costs - from ease of access, to your choice of kitchen counter, but the essential costs are based on the size and quality of your build, as in the following breakdown:
| Small (3mx5m) | Medium (4mx6m) | Large (6mx8m) | |
|---|---|---|---|
| Basic | £14-£18.5k | £22-30k | £44-60k |
| Standard | £18.5-£24k | £30-£39k | £60-£77k |
| Premium | £24-£34.5k | £39-£55k | £77-£115k |
In this article, we have broken down different elements of an extension build and the different kind of costs involved, but the key underlying cost relates to the size of the extension being built.
Speaking to our experts, we have established that the basic price of building an extension is£1,300 to £1,600 per square metre. So, for a 20msq extension (4m x 5m), the cost will range from£25,500 to £32,500.
这些价格不包括20%的增值税。价格区间反映了所使用材料的差异、设计的复杂性、表面处理的质量以及你在英国居住的地方。
这个价格涵盖了建筑的基本要素，建造地基，建造墙壁，为新结构隔热，安装石膏板，增加底层，安装基本的管道和电力设备。
It will not include any of the finishing elements, such as decoration orkitchen installation, which we cover later in this article.
MyBuilder Top Tip
Twice the height, half the price? Some people suggest that adding a second storey to an extension will only cost a fraction of a single-storey build, but the世界杯2022赛程时间表最新 describe that as a myth.
关键因素是整体建筑面积，所以如果你想做大，确保你有相应的预算。
Stages of a house extension project
An extension building project goes through several stages of building, which are broken out below. Establishing individual prices for each section is difficult, as many builders will not separate costs for elements such as groundworks, which are rarely done in isolation from the rest of the project.
However, if you are having an extension built, many homeowners will agree to pay their tradespeople in stages, typically after some of the following elements are competed.
Home extension design costs
You may choose to have an architect or architectural technician draw up plans for the builders to follow, rather than hire a firm to design and build your extension. Architectural drawings may come in around £500 to £1,000 depending on the scale and complexity of the work - for more information, read our guide on how much an architect costs.
Home extension planning costs
Planning permission is not always necessary for an extension project, but in some cases you may need permission from your local authority, which can be around £200 depending on your circumstances, such as if you live in a conservation area. Check out ourguide on planning permission.
Building regulationsare the standards to which all construction projects must adhere and are essential for all building projects in the UK. Building Regulations are designed to ensure buildings are safe, structurally sound, and water and energy efficient.
The cost will vary depending on the size of the build and the type of work being carried out, but will typically be between £300 and £500.
Home extension groundwork costs
The preparing of the site and digging of foundations is essential to making sure the extension is built safely and with structural integrity.
虽然这一阶段的成本很难区分，但如果在这一阶段出现了并发症，例如必须移动下水道或处理树根，它会减慢过程，增加成本。
Home extension construction costs
This is where the main building takes place, building the basic structure with either brick and block or a timber frame.
A roof is built, and interior elements such as plasterboard and a subfloor are added to ensure a watertight structure.
Costs here are typically related to the size of the build.
如今，砖和砌块或木结构的扩建都处于类似的价格点，所以虽然它们在某些情况下可能有各种优点和缺点，但对于一般的扩建工作，主要建筑材料的选择不应该考虑太多的成本。
Home extension fitting costs
Fitting out the extension with features like skirting boards, doors, electrical sockets and switches, as well as necessities like radiators. T
所有这些的成本将取决于你是否想要购买高端材料。
Sliding or bifold doors can cost thousands of pounds per metre, while simple French doors will cost much less.
Home extension finishing costs
There is no upper limit to what you can spend when finishing the extension - every individual element will have a wildly different cost, from cheap carpet that is a few pounds per square metre, to imported marble tiles that will costs hundreds of pounds to cover the same space.
Costs will also increase significantly if you are adding a new kitchen or bathroom to the extended space. As a benchmark, a newkitchencould cost between £8,000 and £29,000, while abathroomcould cost between £3,500 and £11,500.
How long do home extensions take to complete?
The length of time it takes to build an extension will obviously depend on the scale of the build, without even including any time spent drawing up plans and obtaining planning permission (which can take several months in and of themselves).
大概需要三到四个月的时间，从项目开始——清理空间、挖地基、进行最后的润色，以及处理你遇到的任何障碍。
Delays are common, and are often due to bad weather, changes in the plans, and hold-ups in materials being delivered.
With multiple trades working on an extension, backlogs can also occur; for example, plastering can only be done after the electrics and plumbing are in place, so a delay to one will create a knock-on effect for other work to be finished.
Get a home extension quote
We can help you meet professional extension builders near you to get real quotes today.
How do different home extension types vary in cost?
虽然每米的价格是粗略计算扩建成本的最佳方法，但有许多不同类型的扩建可能会对最终成本产生一些影响。
Side extension vs rear extension costs
As the main calculation for pricing an extension is based on floorspace, whether an extension is to the rear or side of a property will not have a large impact on the overall cost of the build.
There will be other factors that affect pricing depending on the design of the extension though, such as how integrated with the original building it is and what structural implications this has, how many windows and doors it has, if a new kitchen or bathroom will be in the extension, or how difficult access is.
Double vs single storey extension costs
Many sources claim that a second storey will be priced at only half or two thirds of the cost of the first floor (so if the single storey extension is 20msq and costs £25,000, the second floor could be an additional £12,500, for a total of £37,500).
However, tradespeople we have spoken with tend to disagree, and say that the majority of世界杯2022赛程时间表最新 will price a job based on the total square meterage - so a two-storey extension with both floors of 20msq floor space will be £50,500.
While it may seem intuitive that the ground floor is the more labour intensive element because of the groundwork and foundations that must be completed, there are a number of additional costs involved in a second storey that are not applicable to a single storey project.
Using scaffolding, working at height, increased structural integration with the original building, changing the roof - all of these factors serve to ultimately balance out the cost.
Masonry vs timber frame extension costs
Masonry, or “brick and block” construction has been the most common way of home-building in the UK for nearly a century, but timber frame projects are becoming more and more common.
Masonry construction sees the structural element built from blocks, with brick or another form of exterior cladding added around it, whereas timber frame uses wood to construct core panels that are assembled on site.
就建设速度和结构效益而言，这两种方法各有利弊，但就成本而言，如上所述，这两种方法是相当相当的。
Bathroom and kitchen extension costs
The two biggest additional factors that can impact the overall cost of an extension is if you plan to install a kitchen or bathroom in the new space.
The price of new kitchens and bathrooms vary widely depending on your requirements and the quality of the products you choose to buy.
As mentioned earlier, the typical price range for fitting a bathroom may range from £3,500 to £11,500, while a kitchen could cost anywhere from £8,000 to more than £29,000.
For more detailed pricing for kitchens and bathrooms, take a look at our pricing guide for kitchens and bathrooms.
Garden room extension costs
Garden room style extensions tend to be very design-focussed, typically single storey with an emphasis on large windows or bifold doors that allows the house to flow out into the garden.
Although you can still use the basic calculation of price per square metre, there are a number of complicating factors that will impact the final price of a garden room project, such as the materials used and the desired features, such as what kind of doors will be used.
Bungalow extensions costs
As above, the main calculation for extension pricing is based on cost per square metre of floor space, so the cost for a bungalow extension can simply be considered along these lines.
How to keep your home extension costs under control
It is important that you only embark on any major project, like building an extension, when you are fully aware of scale of the job and the costs involved.
Set a budget and get several quotations for the work. Allowing yourself a contingency is always a wise move, to help you cover any extra expenses that could arise as a result of delays or issues with materials.
There are ways to save money on a project like an extension build, but it is worth remembering that in order to save the money, it will require you investing more time and effort into it.
For example, you could choose to carry out some of the jobs yourself, such as the final decorating, if you are happy that you would be satisfied with the finish and wanted to spend the time doing so.
You could also source materials, such as tiles and flooring yourself, though a tradesperson may be able to help you with this, and may actually save you money via a trade discount.
The best way to ensure the job is done to budget and with no extraneous costs, is to hire good tradespeople you trust to do the job well. A
good team, who work well together and stick to a timetable, and ensure different phases are ready for other elements of the work to begin, will be the best guarantee of not encountering unexpected bills.世界杯2022赛程时间表最新 .
