House extensions Costs

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Average House extensions cost

The regular cost of House extensions are £52,063 in your area. Costs vary based upon the materials and the company picked. The upper price range can be as high as £76,938. The material costs are in most cases around£10,500.

Average price per House extensions job in 2024

Avg. price low

Avg. price low
£28,438

Avg. price

Avg. price
£52,063

Avg. price high

Avg. price high
£76,938

£77500

£58125

£38750

£19375

£0

Prices based on actual House extensions costs for your area, as reported by local LeadsDoWork members.

House extensions installation cost in your area 2024

Labour cost £27,000
Material cost £10,500
Waste removal £2,500
Time frame: 10-14 weeks

Advantages for House extensions

  • Create additional usable space within in your home
  • Create more room upstairs, additional bathroom or bedrooms
  • Increases the value of your home
  • As your family grows it means you can stay in the same home for longer

Disadvantages for House extensions

  • Will cause a lot of disruption when the existing house wall is opened up into the extension
  • Upstairs windows should be carefully planned not to look into neighbours homes

House extensions Manufacturers

House extensions FAQs

How long do house extensions take?

If you’re about to start your house extension project and wondering how long it’ll take to complete, you’re not alone! This is one of the most common questions that’s asked by homeowners in the UK and across the globe. However, there’s no single precise answer for this as there are multiple factors that’ll affect the length of time it’ll take to complete your home extension. These factors include the size of the construction work as well as whether you’re planning to live in the house after completion or otherwise.

For a single extension, the length of time it’ll take to complete the home extension is normally up to 3 months. So let’s break this down:

As you would have expected, the first step to be taken is the preparation of the site. You start by digging out the footing and preparing the foundation which should take about 2 weeks. This is then followed by the damp course installation as well as the fitting of any drains needed around the extension which will also take a further 2 weeks.

The 5th week will be for the construction of the external walls as well as putting the blockwork in place for the provision of the cavity wall insulation. A further 2 weeks after this, will be dedicated to the installation of the roof structure and the internal walls.

It’s at this junction that you’ll call on your weather proof installer to fit in your uPVC windows and doors. Once done, the gas fitters and electricians will have to be on site to connect power to your new extension building. Subsequently, this will be followed by internal wall plastering as well as breaking through your main house. Once the plaster is dried, decorations completed and all the required furniture and units installed, the extension is ready for use.

How to finance a house extension?

Do you want to beautify and increase the value of your home? If yes, a refurb and house extension is definitely a great option to consider. Depending on your home extension project, the value that’ll be added to your home’s resale value varies. However, the cost of completing a house extension project can be huge, so you just might want to consider your financing options. Fortunately, there are various options through which your house extension project can be funded with each having its own pros and cons. Your specific circumstances will determine the one that’s going to work best for you, so let’s take a look at some of the best options to help you fund your project.

• Home Remortgaging

The process whereby a mortgage is transferred from one provider to the other is known as remortgaging. This is usually done to generate funds for a project by entering a more lengthy repayment term commitment when switching. If you want to raise your funds in a quick manner, this process works best.

• Savings

This is a good reason to cultivate a good saving habits. If you’ve been able to save up some mega bucks then you’d probably won’t have to borrow money to finance your house extension.

• Unsecured Loans

If you do not buy into the idea of borrowing more against your property, you may just be able to apply for an unsecured loan especially if you have a good credit record. A secured loan makes use of collaterals like a car or house to serve as a cover for the lender, meanwhile an unsecured loan is based mainly on the credit managing history of the borrower.

• Credit Card

There are some great benefits that comes with financing your small or medium scale extension project with your credit card. Not only does it offer some real lifeline if problems arise during the project, but you can also avoid paying excessive interest on the investment by ensuring your deal has a 0% introductory rate.

Will my extension be expensive?

It depends on the size and type of extension. Small porches or flat roof extensions are very reasonably priced. More substantial two storey extensions can be expensive. In general, the price is roughly proportional to the amount of space you add to your home.

How much does a two storey house extension cost?

If you’re considering adding a two storey house extension, then setting a budget for this project would be a great way to get started. Similar to a rear extension, a two storey extension usually leaves the rest of the building needing some work and, due to its size, this may imply the re-development of the entire house - which is why they can be very costly. Some of the other influencing factors that can have big impact on a two storey house extension cost includes: your location, the size of the build, complexity of the design ( anything beyond the standard build will normally require more expertise and time), the glazing to be incorporated ( the more the glass used in the project, the more the material cost), as well as the team used.

Generally, when it comes to extensions, the major part of the expenses will be made on the build of the project. This is because it doesn’t only cover the material cost but also the contractor’s overhead as well as the daily rates. At this stage, the extension prices can be determined by the standard of the work that’s being done.

For a fairly average room size of about 18 square metre, the two storey extension should cost within the range of £2,500 to £3,000 per square metre - with the range being determined by the finishes incorporated. Therefore, a two storey extension of about 18 square metre should cost within the range of £45,000 to £55,000. However, this is with the assumption that there are standard window sizes, bathroom suits are modest, and without any need for any purpose joinery or glazing. If you wish to include all these extra features you’ll also have to pay more to make the total cost between £70,000 to £80,000.

How much is a double house extension?

A double house extension is basically a construction to any aspect of your house that elevates up to offer two floors of space. It can be structured to suit your existing home in two storeys or as a side wing on a taller property. If you’re considering building a double house extension, then estimating the cost is a very important task to do before commencing the project. In this article, we’ll give you an idea of the cost of a double house extension so you can estimate yours accordingly.

The double house extension cost depends on several factors that’s specific to your home as well as your design choice. These includes:

• Location of your property. Places like London and the southeast will generally cost more than the other regions due to higher demands.

• Accessibility of the site. The ease of your site’s accessibility also plays a key role in the price.

• Size of the extension. The more the extension’s size in footprint and square metres, the higher the possible costs.

• Materials used in making the roof as well as the complexity of the roof design.

• Your choice of finishing. These includes flooring window and door frames, glazing, underfloor heating and roof lights.

• Your property’s soil type. Different types of soil requires varying treatments as well as materials to develop solid foundations.

Constructing a double house extension is a quite simple build in terms of technicality when its to the side or rear of your house as this can also help you save some money. Generally, considerably expanding your home’s space by building a double house extension will cost within the range of £1,500 per m2 to about £2,800 per m2.

Can I extend the front of my house?

When it comes to extending a home, the rear of the house often comes to mind a lot more than the front. However, this doesn’t mean that you can’t extend the front of your house. This can be done either as part of a renovation project whereby the entire house is incorporated or it can also be done in isolation. It’s possible to extend the front of your house without the need to apply for a planning permission, however, there are a bunch of limitations you’d have to comply with if you wish to carry out with such a project. Sometimes, this may imply that extending to the front of your home is more tedious and tasking than extending your home’s rear. So exactly how far can you extend the front of your home without planning permission?

 

The short and simple answer to this question is 2 metres square area with a height not more than 3 metres. Generally, you do not need a planning permission to build a front porch as long as its area doesn’t go beyond 2 square metres from a public road or walkway. Also, a tiled or slated roof can be as much as 4 metres but other roofs must not go beyond 3 metres in height. If you want to extend the front of your home beyond the restrictions specified, then you’ll have to apply for a planning permission.

 

Extending the front of home can be quite costly, but this can be controlled by not building to the extension to the highest specification, not including an extension on kitchens or bathrooms and more.

What types of extension are there?

There are many different types of extension. For example, you could install an orangery, flat or pitched roof extension, over-structure extension, single or double storey extension or a glass box extension. Which one of these is most suitable will depend on your existing property.

How big can my house extension be?

The holy grail of home extensions is basically the need for additional space for living as well as leisure. However, before commencing your home extension project, you’d probably want to know just how big your new building can be. In this article, you’ll find the answer to this question which is also frequently asked by many other home or property owners in the UK.

Besides your budget, there are two other major influencing factors that can determine just how much extra room that can be added. These factors include whether you wish to carry out the extension project under Permitted Development rights which is usually for a smaller project or you’d prefer to opt for a larger project which is covered by Planning Permission.

Apart from the limitations in the size of an extension under Permitted Development, the extensions are also a lot more affordable and consumes less time when compared to the extensions under planning permission. So what exactly is the size limit for an extension under Permitted Development and the ones under Planning Permission?

For a single storey extension, the maximum size that can be constructed without having to submit an application for Planning Permission includes:

• An extension should have a maximum length of 6m, if you reside in a terraced home or a semi-detached property.

• Extensions for detached properties can have a maximum length of 8m.

• The extension built must not go beyond half your garden’s area.

• The extension should have a maximum height of 4 metres, but in the event whereby the extension is situated within 2 metres of the boundary of your property, it should not exceed a height of 3 metres.

• The extension should not be higher than the highest part of the existing house’s roof.

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