House Extension in city

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.

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.

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.

If you’re planning on adding a house extension to your property, you’d probably be worried about whether or not your proposed extension would require a planing permission. Well, it may be relieving to know that not every house extension project would require a formal consent, and in fact, several extensions are covered by the permitted development rights. Not only can this save you a considerable amount of time especially at the project’s planning phase, but it’ll also save you money on the application fee. In the UK, single storey extensions to the house’s rear can be 3 metres deep for both semi detached houses and terraces or 8 metres deep for detached homes.

So how do you know when you’d require a planning permission for your home extension? Well, if your extension plan fits these criteria explained below, then your project is most likely going to be allowable as a permitted development.

• Extensions, which includes previous additions, must not go beyond half of the original house’s total surrounding land area.

• The main elevation, or side elevation where it fronts the highway, must not be extended forward.

• For single storeys, the rear additions must not extend more than the original house’s rear by more than 3 metres in both semi attached homes and terraces (4 metres for detached houses).

• Extensions to the side must be a single storey with a height not exceeding 4 metres and not going beyond 50% of the original house’s width.

• Extensions hat within 2 metres of a boundary should have a eaves height not more than 3 metres.

• Multi storey addition must not extend beyond the original house’s rear wall by a maximum of 3 metres or 7 metres of the boundary opposite the rear wall.

• Permitted development rights do not apply in listed buildings or designated areas.