garage conversion a good idea

Is Garage Conversion A Good Idea?

There may come a time when you look around your home and realise it would be perfect if it just had a bit more room. Maybe you could use a playroom for your young children or a rec room for your teenage gamers. 

Maybe you’d like a home office or a workout room. Whatever the need, one way to get additional space is to convert a non-functional area of your home into usable square footage.

While an unfinished basement or attic has been the traditional choice for homeowners, garage conversions are becoming more popular. But is losing the parking and storage worth the additional space? Here are some important factors to consider.  

FAQs About Garage Renovation

A garage conversion could add up to 20 per cent to the value of your home, while you'll gain valuable extra living space that's less prone to planning complications. So if the cost of the project is less than the extra value added to your property, this works out as a cost-effective way to add more space.

A detached garage conversion is a great way to add space to your home, especially now that most of us work from home. Since it is separated from the main house, you have the freedom to make as many changes as possible without disrupting your family's routine.

Convert your garage. If you have off-road parking and depending on where you live, you may find converting a garage can significantly increase your home's value – by as much as between 10 and 15 per cent.

A single-car garage conversion can take anywhere from one week to one month, depending on the scale and scope of the conversion. If multiple tradespeople from different firms are contracted, make sure they'll be available when they're needed during the conversion.

Planning permission is not usually required to convert your garage into additional living space for your home, providing the work is internal and does not involve enlarging the building.

Pros, Cons, Costs And Design Advice

Is a garage conversion a good idea? For many homeowners, the answer is yes. The trade-off of covered, off-road parking and storage against actual living space is worth it for many homes where extra room is in short supply. 

What's more, it's likely to be cheaper, quicker and easier than building an extension from scratch, meaning that while it won't be a cheap project, you can expect it to be one of the more affordable ways to add some square meterage to your home. 

If you're wondering if a garage conversion is right for you, we've got you covered. Our experts have pulled together all the most important considerations when converting a garage so that you have all the information you need at hand. 

From planning permission and Building Regs to how the process works, how much it costs and how you'll need to improve the fabric of your garage to make it suitable for a conversion, you'll find it all in our ultimate guide. 

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Should I Convert My Garage

It doesn't matter whether your home’s garage is integral or detached. Converting it into habitable accommodation is one of the quickest routes to increasing living space. 

You’ll be gaining extra room from the existing footprint of the garage without actually building an extension from scratch, as you would for an extension. Plus, a garage conversion won’t use up precious garden space.

A garage is also a good size for many uses. There are plenty of garage conversion ideas to explore — from an extra bedroom or a utility room to spaces like games rooms and home gyms. 

This type of project is often received more favourably by the planners, too, as they usually involve fewer alterations to the house's exterior. As you’re working with the existing structure, you won’t necessarily need to dig out new footings. 

It is always worth getting the existing footings checked out, though, especially if you want to build a second storey on top of the garage later.

“If you’re working with an attached garage, removing the dividing walls can add a significant amount of space to the most lived-in areas of your home,” says Sabatino Torchitti, head of quality in Building Regulations at architectural practice Resi.

Carrying out a garage conversion makes good sense if you’re undertaking a larger house remodel at the same time. You can rejig the floorplan to establish a layout that flows from one zone to the next. 

Be aware, though, that tapping a wall and hearing a hollow sound isn’t necessarily proof that it’s not load-bearing. If you’re unsure, it’s worth bringing in a structural engineer to check.

Is My Garage Suitable for Conversion?

Before moving ahead, there are still numerous considerations to factor in, especially if the scheme is to deliver the results you want. “You’ll need to consider how the garage is constructed and what you want to use it for,” says Jude Tugman, managing director at Architect Your Home. “These criteria will impact the cost of the conversion.”

Do you want more light, a quiet study, a utility area or an extra bedroom? Additionally, if you’re doing away with your main storage space for bikes and tools, you’ll need to work out where these items can be moved.

Whilst a garage conversion is, in the majority of cases, a brilliant way to add space and value to your home, there are certain instances where it might not be a viable option or might cause more problems than it is worth. Consider whether this project is right for you by thinking about the following: 

  • Will the work mean one or more existing rooms will frequently be rendered unusable by building work?
  • Remember that you will be held responsible for the legality of work done on your property. Time and energy will be required to supervise work, being present to allow tradespeople access and make design and other decisions.
  • Will planning permission be granted? Is the house listed or in a designated area? 
  • Might the cost of reinforcing foundations, a new roof etc., mean you are paying more than expected?

If on inspection, you see that water is lying in pools on the flat roof, this can cause problems in the new space beneath. The roof will need repairing, and the underlying fabric of the structure checking for damage.

Occasionally it is necessary to replace the entire roof. This is sometimes a welcome discovery — swapping a flat roof for a pitched design can help tie the new space in with the rest of the house aesthetically, although you may require planning permission.

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Do Garage Conversions Need Planning Permission?

Do I Need Planning Permission? The short answer is: probably not. 

Most integral garage conversions will usually fall under Permitted Development, meaning planning permission is not required. However, it is still best to check with your local authority. Resi estimates that only 10% of garage conversions will require planning permission. 

If you live in a conservation area or a listed building, you will almost certainly need planning permission. It is also worth checking for any planning conditions attached to the house or garage when constructed (i.e., the garage must remain as parking) before beginning works. An application will need to be submitted to remove the conditions.

In some areas, especially Conservation Areas, PD rights for garage conversions have also been removed. This may also apply to areas where on-road parking is an issue. 

If the conversion falls under Permitted Development, applying for a Lawful Development Certificate (LDC) is a good idea, particularly if you aim to re-mortgage or sell the house.

Even if Permitted Development rights have been removed, you may still be able to convert a garage, but you'll need to make a householder planning application. 

If you are converting a separate, stand-alone garage as opposed to an integral one, then you may have to apply for a change of use.


How Much Does a Garage Conversion Cost?

At the very least, you will need around $1,000/m2 for a garage conversion. This price includes construction, design, planning, Building Regs and a structural engineer’s costs, but not finishes and furniture. This could easily rise to between $1,500 and $2,000/m2 depending on the level of work and the finish you choose.

“For a single garage conversion, you’ll need to budget around $20,000, with some variation due to your choice of materials and fittings,” says Rob Wood, managing director at Simply Extend. “For a double garage, that figure would be more like $30,000.”

Of course, there are caveats for all these prices. Project costs will vary depending on structural changes, utilities and plumbing, which can push prices up (and if your project is in London, you should always expect to pay at the top end of the range). 

It's also worth noting that construction material shortages are causing a spike in many building materials, from timber and steel to plaster. Some estimates suggest that building quotes have increased 10% year on year to factor in these increases, as well as an increased workload for builders overwhelmed with new demand and less available labour. 

You should expect to wait several months before a contractor can start your garage conversion at present — you may find there's a good reason a builder has immediate availability and that they're a company to avoid. 

Other factors will affect the overall cost of your conversion, from the condition of the existing structure to the fit-out spec and level of finish. If the foundations, walls or roof are in questionable condition before work gets started, the cost of putting them right could potentially result in a bigger outlay than you budgeted for.

A final tailored quote would also take into account waterproofing, insulation and the integration of the conversion with the rest of your property.

Before you begin work, be sure to familiarise yourself with the factors that are likely to affect the cost of your garage conversion, including:

  • the foundations need reinforcing
  • the walls, floors or roof are in dubious condition
  • the ceiling height needs to be raised (you need around 2.2-2.4m of headroom once the floor has been raised to 15cm above the external ground level)
  • design fees
  • planning applications
  • The services of a structural engineer.

You could also use a recommended builder — most good builders will be able to take on a garage conversion.

Another option is to use a garage conversion specialist. These companies usually have a wealth of experience, but, as with all of the above options, view completed projects and speak to past clients first. 

A garage conversion specialist should have plenty of experience in terms of dealing with any planning issues surrounding garage conversions, as well as building regulations.


Do I Need an Architect For a Garage Conversion?

Whether you decide to use an architect, another house design professional or come up with designs yourself is a personal decision that should be based on the scale and complexity of the project. 

Using an architect, an architectural technologist, or another design professional will mean expert design input and ideas that you might not have thought of. A design professional will also have useful trade contacts and experience dealing with Building Control.

When it comes to architect costs, expect to pay from as little as $1,200 right up to $3,000 for design fees, depending on the complexity of the design.

Some people choose to come up with a design themselves and carry out a DIY garage conversion — a good option for those with limited funds and the spare time to get stuck in.

Can I Make a Garage into a Two-storey Extension?

When converting an integral, single-storey garage into living space, it is worth considering the space above it — could adding a storey above be an option? 

This is well worth thinking about as a way of gaining extra first-floor space without increasing the overall footprint of the house.

Creating a double-storey extension means more work and expense, but the end value of the house should make it worthwhile. 

The existing foundations will almost certainly need to be checked and upgraded, and there will be further Building Regulations to consider. For example, the garage ceiling and new floor in the upstairs space will have to achieve a minimum of 30 minutes of fire resistance.

Additionally, there will be thermal and sound insulating considerations to consider.

How do I Make a Garage Conversion Look Seamless?

Ideally, you want to make your garage conversion look like part of the rest of your house, as opposed to a converted garage. This should be something you can work on with your chosen designer.

One exception is in the case of partial garage conversions. This is where the front of the garage remains unchanged both internally and externally, while the rear section of the garage is incorporated into the house. This allows you to retain some storage space while gaining a little extra living space — perfect for those after a utility room, a little extra kitchen space or a playroom.

Ensuring the materials used for the cladding and roof (where there is one) match or tie in with those on the main house ensures a seamless finish, matching the window and door style.

Alternatively, you might wish to adopt a contemporary take on the design and highlight the garage as a new element of the house, choosing a modern cladding or render.

A new cladding will overcome any issues sur- rounding how the old opening for the garage door is concealed — a badly bricked-up opening is a definite no-no.

Building Regulations

Do I Need Building Regulations For a Garage Conversion?

A garage conversion will most certainly need Building Regs approval. 

You or your builder must stick to the Building Regulations when converting an attached garage into a habitable space. Regulations apply to various aspects of the construction, including:

  • thermal performance
  • acoustics
  • fire safety
  • ventilation.

The LABC website is a good starting point for information regarding the Regulations surrounding garage conversions in England and Wales.

A building notice or full plans application will need to be submitted to building control as part of this process. Your local building control department will then register the conversion and carry out inspections throughout the project, then issue the final certificate on completion.

Do All Garage Conversions Need Windows?

Garages don't always open onto hallways, and if this is the case for your build, you may be required to install a window that acts as a fire escape route under Building Regulations. This window is subject to certain criteria, including its height from the floor, how it opens and the size of the openable section:

  • Width and height no less than 450mm
  • Maximum 1100mm from the floor level
  • The openable area of 0.33m2 at the bottom of the window 
  • Generally, side hung windows are required

If your garage conversion opens directly onto a hallway providing a direct protected route to an external door or has access to the exterior from within the garage, the window won't be required. 

Bear in mind, windows within garage conversions under Permitted Development are largely only allowed in the section replacing the garage door. Any new windows added to the side of your home may require a planning application.

Key Works Of A Garage Conversion

Making a garage into a liveable space isn't just a case of moving your furniture into it. Here's the basic process you can expect for jobs required during a garage conversion. 

  • Level, insulate and damp-proof the floor. 
  • Infill the garage door to create a solid wall if required
  • Insulate the walls and the roof 
  • Plasterboard and plaster 
  • Decorate 

Can I Brick Up My Garage Door?

The existing garage door is one element that needs addressing in your design. The most common route would be to infill this using walling that matches the building or using blocks before using house cladding or house rendering to unify the new wall with the existing structure. 

It may also be possible to retain a door or use glazing in the infill to bring natural light into the space, reducing the additional load on the existing foundations. 


Do Garage Conversions Need Foundations? 

One of the key elements of converting a garage is blocking up the existing garage door opening (with an infill wall) — perhaps adding a new window or entry door.

To add an infill wall, you’ll need to establish whether the garage foundations were continued beneath this opening and the concrete slab is adequate to support the new wall. This may involve digging a small trial hole in front of the concrete slab to check.

If the existing concrete slab is 200mm or over, this is generally adequate to extend straight up with new brickwork.

"If the existing slab is not adequate, there are typically two options," says Stuart Letts. "Either a 1m footing will have to be dug and filled with concrete, or a 140mm x 100mm concrete lintel can be added into the wall on both sides below ground level. The new infill wall can then be built on top of that."

It will also be important to test foundation strength when extending over a garage, as this greatly increases the load exerting pressure on your foundations. 

Speak with your designer, builder or structural engineer to ascertain the suitability of your foundations. 


With housing costs so high in so much of the country, it can be easier to buy a smaller property and instead invest in expanding its living space over time. One place to start: Converting a garage into something other than a parking spot. 

But there are many factors to consider about such a project, including the impact on a home's resale value and the total price tag (which may be more than you bargained for). If you've been contemplating a conversion, here's what real estate, home design, and insurance professionals think you should know first.

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