What is the average price guide for building in Perth?

In Perth, the average costs for various building services can vary significantly based on the type of project. Here’s a breakdown of typical prices for 2026:

## House Extensions A typical house extension in Perth can range between £1,200 and £2,000 per square metre. This means if you’re looking to add a 20 square metre extension, you would be looking at an expense of £24,000 to £40,000. Considerations such as design, materials, and the complexity of the project will influence the final price.

## Loft Conversions Loft conversions generally cost around £30,000 to £50,000, depending on the level of finish and space you want to create. This often includes structural work, insulation, and electrical installations, which should be carried out by certified professionals, preferably those registered with NICEIC for electrical works.

## Garage Conversions For garage conversions, expect to spend between £10,000 and £20,000, contingent on your desired outcome and whether you need planning permission. Always ensure your builder is certified with Trade Associations to guarantee quality workmanship.

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