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Architect Tips

Why have build costs increased?

Why Have Build Costs Increased?

One of the biggest questions we often hear from homeowners is “How much does it cost to do an extension?” In short, most home extensions can cost around £1,850-£2,750 (m2). So, for a 30m2 single storey extension, you could be looking at between £55,500-£82,500 (shell finish), plus, VAT at 20%.

However, we find ourselves having to further explain, although this price has been quoted in most construction magazines, there are still many variables to consider as part of this question.

For example; where’s the site located, what size and volume will the extension be (single or two storey), what type of materials to be used, down to whether the existing windows and external doors will be retained as part of the scheme or be replaced with new to meet current standards (all whilst increasing the home’s kerbside appeal) etc – which can all add up on a project’s final price.

In the current market, because of Brexit, Covid and other world events, we have a perfect storm – sending both construction material costs soaring, as well as huge material shortages – both of which add uncertainty to a build.

The supply problem is particularly acute, especially on lead times for materials (timber, tiles, concrete, bricks, steels etc), not to mention product shortages (windows, doors, sanitaryware, kitchen carcases to name a few), and things having to be sourced from abroad, as many UK manufacturers have struggled to catch up to demand or many items not being locally made.

There are ways to deal with this through the build; making decisions early and procuring things with long lead times as early as possible so you can secure things well in advance of when they will be needed.

Also be mindful, that with costs increasing, if your build team is tied into fixed costs and running multiple projects you may find that to cover shortfalls on price increases, they are moving money from one job to another – this is a route to disaster and increasingly we are starting to see small scale builders go into liquidation.

To protect yourself only pay for work that has been completed – this is standard practice and if you are told otherwise be wary. Construction contracts do not require deposits to be paid upfront and so you are protected on monies being paid relating to works that have been done.