Bush Builders

The Price of a House Extension in Essex for 2018


Wondering just how much a 2018 home extension will cost? Our guide is all you need to get a price estimate for your property extension before you seek out quotes.

Make sure you know what to expect going into your house extension quote to avoid any hidden surprises.

A beautiful renovation completed by Bush Builders in Brentwood Essex
A single storey extension by Bush Builders



House extensions are an increasingly popular way to improve your home, and it’s not hard to see why. When it comes to choosing between moving or renovating, building an extension is often the more economically efficient option. Alternatively, you may be considering a loft conversion for which we have a cost guide also.

House extensions can:

• Add space and increase functionality
• Add value to your property
• Provide an alternative solution to the stress of buying and moving
• However, it’s important to get a proper understanding of the current rules, regulations and costs involved in a home extension before you get planning.

Of course, the overall cost will vary depending on a number of other factors, such as:

• Extension size
• Geographical location
• Soil type
• Standard of specification
• How much glazing you plan to use
• What the extension will be used for
• Accessibility and condition of the existing building

Generally speaking, it is likely that your budget will be split roughly 50/50 in terms of construction costs and interior costs, but there are many individual expenses to consider.

The following gives a breakdown of the average costs you’ll need to account for when building a house extension.

House Extension Example
A rear extension completed by Bush Builders in Romford

Adding another storey to your house extension will not double the costs – in fact, as you have already factored in the cost of your foundations and roof, it often works out to be not much more expensive than a single-storey extension. This is important to note when balancing your costs against the added value of your extension.

As a general rule, you can expect to add around 50% (if both storeys are the same size).

So the approximate cost of a 5m x 5m double-storey house extension will be:

Basic cost: £50,000 + 50% = £75,000
+ VAT: £15,000
+ Fees: £11,250
= £101,250