How much does a garage conversion cost? This is what experts say you can expect to pay and how to keep costs low

A garage conversion can be the perfect way to gain extra space within your home without extending its footprint. Utilising what is often wasted space, used not, as originally intended, for housing a vehicle or two, but for dumping all kinds of things no-one quite knows what to do with, this is a structure that holds so much potential.

Converting a garage comes with other benefits too. Very often no planning permission is required to carry out the project, they cause little in the way of disruption to everyday life and they have the potential to boost the value of your home too.

Of course of all this does come at a price and that is where our guide comes in. We explain how much to budget as well as the areas where you can make some savings.

How much does a garage conversion cost?

Predicting what any type of home extension or improvement will cost is never going to be an exact science – there are just so many variables that can influence this. In short, the garage conversion ideas that you are hoping to create are unlikely to come in at exactly the same price as someone else's.

'Costs of converting a garage into a usable living space will vary depending on the size, complexity and and level of polish required to make it look good,' explains Alexandra Hull, managing director of Back to Front Exterior Design. 'The nuts and bolts will typically cost between £15,000 and £25,000.

'Core expenses include insulation, electrics, heating, windows, flooring, and labour,' continues Alexandra. 'If plumbing or structural changes are required, expect higher costs.'

Alexandra Hull

Back to Front Exterior Design are specialists in remodelling ugly houses into beautiful family homes. MD and principal designer Alexandra Hull is the daughter of founders Yolande and George Hess and grew up on building sites, learning from her parents at a young age. Over the years Alex has been involved in remodelling and refurbishing hundreds of high-end residential properties, undertaken developments and has taken a very hands-on, DIY approach to her own projects.

What elements make up the cost of a garage conversion?

Just as when building an extension, when calculating what your garage conversion project is likely to cost, it is useful to understand the individual elements that go towards these overall figures. In this way, you are more likely to be able to see where savings could be made, as well as avoiding any nasty surprises.

In general, according to Paula Higgins, CEO of HomeOwners Alliance, the cost of a garage conversion will be made up of the following:

• Professional services, such as architect or designer fees.
• Planning permission or building regulation approval fees.
• Structural engineer services, if necessary.
• Structural reinforcement (if needed) of walls and roof.
• Upgrading the floor: levelling, damp-proofing, and insulating.
• Infilling the garage door, often by bricking it up.
• Wall and roof insulation.
• New windows and external doors.
• Installing or upgrading heating and electrical systems.
• New plumbing.
• Decoration.

Paula Higgins

After spending 15 years reforming housing policy in government, enough was enough. Homeowners needed a voice and HomeOwners Alliance was born.

What factors affect the cost of a garage conversion?

While it is possible to estimate what a standard garage conversion will cost, it is useful to understand the decisions you will be faced with that could affect these figures.

In some cases, lower costs than those stated above can be achieved, according to Paula Higgins.

'The average cost to convert a garage ranges from £5,000 to £7,000, according to the builders and architects we spoke to,' says Paula. 'However, this cost can rise depending on whether there are any structural alterations needed for adding plumbing and utilities (for example if you are planning a bathroom to be added into the space.) The condition of the current garage also plays a role in the overall cost.

'Additionally, if it’s a detached garage rather than integrated into the house, this will cause costs to rise,' continues Paula. 'A detached garage will require a change of use application from the local planning authority. In addition it may need new or reinforced foundations and additional costs for bringing electricity and plumbing to the building.

'Other factors that increase costs include its condition and the type of structure and whether or not repairs to walls, floors or roofs are required,' adds Paula. 'If it’s in particularly poor condition, it may be cheaper to demolish and rebuild.'

How can you reduce the cost of a garage conversion?

If these figures were a little higher than you had budgeted for, fear not – there are ways to shrink them a little.

'Work within the existing structure to avoid major alterations as much as possible,' advises Alexandra Hull, who goes on to make some more cost-cutting suggestions.

'Tackle easy DIY projects, such as painting or decorating, yourself,' she says. 'And always get multiple quotes, clarifying exactly what’s included.

'Early planning and realistic expectations are also key,' continues Alexandra. 'Even a basic cost breakdown can help steer your project in the right direction – without blowing the budget.'

Will a garage conversion add more value than it costs?

If you are going to the trouble and expense of converting your garage, you are probably going to want some reassurance that the new addition will add value to you home as well as extra space.

According to HomeOwners Alliance, you can expect an uplift of around 20% in value after carrying out a well-designed and properly constructed garage conversion, making this a very worthwhile project.

'Converting a garage into a liveable room can be a relatively low-cost way to expand your home's usable space,' points out Paula Higgins. 'Unlike an extension, a garage conversion often doesn't require new foundations or external walls, and many garages already have power supply in place.'

FAQs

How long does a garage conversion take?

Even if you have weighed up garage conversion and extension costs and decided that converting your garage is the best way to get the additional space you need for the budget you have available, you will most likely still be keen to know how long this project is going to take, from start to finish.

According to Checkatrade, the average garage conversion takes between three to six weeks, although this will obviously very much depend on the condition of your existing garage, what you intend on using the new space for and the kind of specification you are aiming for.

If you plan on carrying out a large proportion of the work on a DIY basis, this will usually mean longer timescales too.

If, on reflection, you decide that a garage conversion isn't quite right for you, take some time to consider a few loft conversion ideas – the extra space you crave might just be lurking in your attic.