Building service providers, specialising in renovation & domestic extensions

Cost of an extension

Cost of an extension

We always get asked the this question first when we meet with customers.

How much will an extension cost?”


The answer is never straightforward for two reasons.

You should really have a budget in mind and have the strength to stick to it.

 How much do you actually want to sepnd? Be realistic!


How can we you be sure you can do both of these things, here are some top tips to help you!



The devil is in the detail

From the beginning, decide what it is you want the extension to do for your home. Yes, make it bigger….. but for what reason? Are you looking to extend both downstairs and upstairs and gain an extra room or are you just looking additional living space in the kitchen area? It is advisable to have some firm ideas before you speak with any planners and builders, and if you are stuck, they might be able to help you through this phase?


Create a breakdown of extension costs


Create a list of each of the elements and provide a figure next to it.

Don’t forget to add additional costs like, legal fees, landscaping, decorating etc. These can easily be forgotten.

Creating spreadsheet for this kind of project is advisable so you know from the et go, what price brackets you are working with and that if there is contingency pot allocation, that could be wise use of an additional money you have available.

The internet is a great way to research and get an idea of costs, but be mindful that they can sometimes be inaccurate and you missout on the additional accesories you my need to complete the work.


Assess your finances


You might be considering an extension and not be sure how you will fund the project, there are a number of ways you can consider.

If the project is around the £30,000 mark you could take out a personal loan, this does require a secure repayment plan to be in place and to take into consideration any interest payments to be included.

Another option is to remortgage on your existing mortgage. This will allow you to pay off the original mortgage and, in theory, leave you with enough cash to finance your extension. It is definitely worth speaking with your mortgage or financial advisor to find out the best way to apply for any mortgage products as you may finding switch providers or creating a stage mortgage plan can free up the cash you need.


Research, research, research


The worldwide web has opened up your home to endless possibilities and the majority of the information you need to get outline costs is already out there, you just have to go and take a look. Understanding what a range of prices for products and services are, will help you to make an informed decision when asking for quotes, getting prices and taking on a service provider.

Personal recommendation can be a good start as you would hope friends and family would guide you to quality trades and services. Alternatively, there are a number of professional directories and associations which genuinely recommend services and companies based on their recommendations.

We are lucky enough to be one of the few building firms supported by The Which Trusted Trader organisation, part of the Which magazine group. This is their independent assessment of our services and work provided. We don’t pay to be part of this.


Think to the future


So, you have your finances in place, you have your spreadsheet, what is next?

It’s time to start briefing, maybe starting with a chat with your local planning officer is permission is required and we would always advise getting professional advice from an architect, we can help you with this.

We price our projects fully and take a lot of care an attention to make the quote is fully broken down and comprehensible. Once everyone is happy, we will draw up a contract so everyone is clear of what it expected, and when work will commence.


And finally – Stick to your plan


Every budget can be challenged with unknown issues popping up, this is where your contingency can help, but don’t be swayed into other mini projects in your existing home, - stay focused.

Enjoy your extensions planning and don’t forget we are here to help anyway we can.


Get in touch with us here, if you would like to find out more. Call us on 01423 360622 or drop us a line at


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