Budgeting For Your House Extension: A Comprehensive Guide
Home improvement works and extensions can have significant benefits, but they can also come with significant costs. Whilst it is impossible to give a definitive cost for your house extension without using a quantity surveyor or collecting detailed quotes from contractors, this blog will help you to formulate a ballpark budget.
Single Storey Extensions
Adding a single storey extension is one of the most popular ways to add space to your home. With a single storey extension you can add an additional room/s or add extra space to an existing room.
The cost of adding a single storey extension will depend on where the property is located, how big the extension is and whether you are planning on having any alterations made at the same time.
A basic single storey extension with uPVC windows and doors can cost between £2,000-£3,000 per m2. If the extension includes a new kitchen, you should expect to pay an additional £15,000 to £40,000. £15,000 will typically cover a low to mid-range design complete with units and some appliances.
Double Storey Extensions
Adding an extra storey to your home will save costs on groundwork but you’ll need to evaluate the existing structure. You may need to have structural calculations or a survey carried out before you can continue with your plans.
The cost of adding an additional storey will vary depending on the size and type of property, but you should expect to pay minimum £2,200 – £3,400 per m2.
Structural Opening – Steel Frame
If you are looking at adding a new opening to your home on a structural wall then you will need to consider the cost of a steel frame. The steel frame is necessary to provide stability and support for the new opening.
It is estimated that with all costs included, the steel frame will cost between £3,000 – £10,000 depending on the size of your property.
Loft Conversion
Loft conversions are a cost effective way of adding extra space to your home – loft spaces can be used in a huge variety of ways from home offices, extra bedrooms to craft rooms & home cinema.
The cost of a loft conversion is dependent on the roof structure and end result required. Sometimes, removal of the roof is recommended which can add significantly to the cost.
For loft conversions, we recommend budgeting between £1,800 – £2,800 per m2.
Basement (under house)
If your property allows it then adding a basement to your home can be another option of adding extra living areas.
There are two ways in which you can go about doing this, either by digging out the ground under your house or by using an excavation company to dig a hole underneath your home. Both methods have their own merits, with digging out being cheaper but potentially more difficult and excavation being easier but costing more.
Depending on the method you choose we would suggest budgeting between £2,500 – £3,500 per m2.
Basement (under garden)
A basement can be created under gardens or driveways, these have grown in popularity in recent years especially in city areas where space is limited.
Your architect will consider soil type, the height of your water table and drainage & sewers when designing your garden basement.
A good guide on costs is £3,000 – £4,000 per m2.
Chimney Removal
Removal of an unused chimney can create extra space. If the chimney is load bearing, you will need to consider if removal will affect the structural integrity of your building.
Chimney Removal costs vary between £6,000 – £10,000 – height, access and the type of construction of your home will all have an impact on your quotation.
Internal Refurbishments
Cosmetic refurbishments include decorating, painting and carpentry. You may also need to include electrical & plumbing costs. As these works don’t involve any structural alterations they are cheaper than many of the other jobs involved in home improvements.
We advise budgeting £30,00 – £40,000 for cosmetic improvements and £60,000 – £80,000 for electrical & plumbing contractors fees.
Additional Costs to Consider
Once building work is completed, it is important to think about the costs of new kitchens and bathrooms. You will also need to think about how to cover costs of new appliances, furniture and fixtures when budgeting.
Depending on whether you opt for low, mid or high end specifications you can expect costs to range between £6,000 and upwards of £50,000 for higher end bespoke sanitary ware & cabinetry.
It is worth noting that materials and labour will differ depending on where you are located so please use this blog as a starting point for your project. All the above are ball park figures and are exclusive VAT and subject to materials and finishes etc. We always recommend that you work with an architect right from the start of the process. Architects can help you get the maximum value from your budget and ensure that any potential problems can be flagged before they become costly mistakes at a later date.
If you need any help or advice with your construction plans please contact us and we will arrange a free online consultation here we can discuss your goals and how we can help you to achieve a stress free plan for your dream space.