All prices listed on this site are based on real figures that an individual could actually be quoted. We do not use guesses that are look to made precise numbers. This page tells you where our estimates come from, how we check them and what they don’t cover so you know exactly how much you can rely on them when planning your garage conversion cost.
Where Our Numbers Come From
We don’t just check our prices against one source. All price ranges on this site are calculated from a number of up to date UK sources. These include known quoting and trading platforms, contractor cost guides and publicly available pricing data. We look at the numbers and we narrow it down to a range that represents the market, not just the number that comes up the most.
For anything related to planning permission or building regulations, we use the original legal or government source where possible. This includes Planning Portal, GOV.UK, GOV.WALES and legislation.gov.uk. We do not simply rely to the rules as some other website explains them. Some elements of planning legislation are less simple, for example the rules relating to permitted development and existing detached garages. When there is real uncertainty, we explain it instead of giving a definitive answer.
How We Cross-Check Figures
When we set or update a cost range, we look at multiple separate sources for the same type of job. We refrain from taking one guide’s figure and turn it into fact. When we see similar numbers from multiple sources, that agreement helps us shape our published range. If the figures are very different we look at the reason why. The difference may be the region, the specification or work included. Sometimes one of the sources simply is out of date or based on limited information.
We also take very close looks at sources that seem to be copied or machine-generated. We do not regard multiple different websites using almost the same text and figures as their own independent sources. This is one of the things we take into consideration when deciding how much weight to give to a figure.
How Often We Update Our Prices
Construction and material costs vary over time. We don’t just publish a figure and leave it, we evaluate prices across the site with current market data. Where a page specifies a year or period, the figures are calculated based on the market data verified for that year.
What Our Estimates Don’t Include
A published range of costs is a just a starting point to help you budget for the conversion project. This is not an actual contractor quote substitute. Our figures do not include:
- The specific condition of your garage, which can change the price significantly
- Local labour rates, which can vary even within the same town
- Problems that only become clear when a builder visits the property, such as poor access, damp or hidden structural issues
- VAT and payment terms that are specific to an individual contractor
The calculator and quote tools on this platform are meant to provide you a more personalised estimate and help you get actual quotes from local contractors. These will consistently be more reliable for an individual project than a generic published price range.
Editorial Independence
We’re not owned by a contractor or construction company and we’re not accepting money from a specific contractor to distort the numbers we publish. Our quote matching service helps you find vetted local contractors but the cost data provided on this site is researched and maintained independently from the contractors that you may be matched with.
Spotted an Error?
If you see a figure on this site that looks out of date or wrong or you’ve had a real quote that is wildly different compared to one of our published figures, we want to hear about it. We take feedback from real quotes seriously. It’s probably one of the most effective ways to keep our data accurate and useful.