Extensions Over Garage: An Ultimate Guide To Get You Through

by | Mar 24, 2022 | House Extension | 0 comments

The blessing of building or having a garage in your home is priceless. It adds space to your home, but it also provides you with an extra room. Many people consider their garage to be heaven and an extension of their home. However, the size of the garage depends on the approved land you have for building a garage. In addition, you can extend your garage by taking further permission to add more space or convert it into something exceptional. To know the aspects of extensions over garage conversion, I suggest you stick to the end of the article. We have the best guide on cost over extensions of the garage for you.

Cost To Build An Extension Over The Garage

Are you aware of What is the cost of extending over a garage? If not, then let us guide you
extension over the garage

If you are passionate about building on top of garage, then the first and the foremost important thing you should put forward is the pricing. You can make various things out of your extended garage, including a library, a bedroom, an ensuite or even a gym, but all of it need money.

If you plan to extend the garage to an already existing one, it will cost you much less than usual. You can work on already existing blueprints. You will not have to build it from scratch but continue what has already been done. Building on top of a garage might seem like a good idea, but depending on how big and solid the garage is, you may be better off rebuilding it to extend your dreams.
Extensions over garage in London cost in average between £1500 to £2500 per square metre depending on the area. Depending on how complicated the construction is, a new building built atop an existing structure could cost approximately £1000 per square metre.

Extension Over A Double Garage

In addition to adding the main bedroom and family bathroom, double garage extensions give you more living space. Depending on what you want to achieve, you can spend up to £50,000 for an extension over a single garage, but the cost can be 35% more. The prices are likely to rise significantly if the garage is underpinned. It could also be structurally problematic. If another room used to be there, you can also relocate walls or remodel a bathroom or kitchen.

Building An Extension Over A Detached Garage

Building work won’t affect your home; it may even be a less complicated project. You can certainly build an over garage extension on a detached garage. Adding a guest room or home office to a detached garage would be excellent. You must also provide a way to reach the loft space, possibly a staircase in the garage or otherwise an external staircase. Furthermore, some detached garages don’t have adequate foundations to support greater brickwork and may need structural surveys and work on the foundations to accommodate the added building work.

Planning Steps

You can add extra space to your home quickly and inexpensively by converting a garage. In addition to increasing your home’s value, a garage conversion or extension also adds value. Planning a garage extension is no different than planning any major construction project.

Hunt For An Architect

When planning your garage project, it is worth talking to an architect to gauge the amount of work required. For this, hire a certified architect and let him suggest how you can extend your garage. Consequently, you’ll have a clear idea of what you want and be able to exclude anything that isn’t feasible while also ensuring that your extension is of high quality so that it seamlessly blends in with the rest of your home.

Approval Of The Plan

Garage conversion are generally permitted if they require mostly internal work. No planning permission is needed in this situation. If you wish to make significant changes to the garage’s exterior that will change the overall appearance of your home, you might need full planning permission. It is always good to check whether planning permission is required before spending any money on an extension. You may need to inform you local council for change of use.

The Building Code

Building regulations also apply to adding a garage to a building. In complex conversion projects, complete structural plans may be required, but the mandatory 48-hour notice scheme may be sufficient depending on the complexity and nature of the project. The inspections examine damp proofing, ventilation, insulation, fire safety, and energy efficiency. It is crucial to ensure that the walls and roof are watertight before the project begins. It is impossible to do this before construction begins.

Things To Consider

Ceilings & Walls

Typically, garage walls will be constructed from plain-faced block material for the majority of the garages. The costs will be more if you do use plasterboard and paint. You need to add about 40 pounds per square metre. As for the ceiling, exposed rafters are also standard; however, if plasterboard and paint are required, this would also add to the cost.


In London, the most common materials for garages are wood, metal, and brick, all of which have advantages and disadvantages. It is significantly more expensive to build a brick garage, but the value of your home will increase right away. Furthermore, brick garages are harder to break into than open ones, and brick garages are easier to keep warm. Turning your brick garage into your fifth bedroom might even be possible.


If you plan to construct a garage, make sure your vehicle will have a parking space. As with any construction project, the size of the garage is the most crucial factor to take into account. An average modern car has a width of 1.98m, a length of 3.97m, and mirrors that measure about that size.

Is Extending Over a Garage Possible?

If the building project has been completed, the local authority should be able to prove that it has been met with a copy of the original drawings and a completion certificate. When that happens, it is dependent on the foundation and walls of the existing building. If built along with the original house, recent garages are likely to have enough foundation depth to handle the additional weight.

Is It Disadvantageous To Build An Extension?

Aside from the many benefits of extending your home, you may also experience some disadvantages.
You may lose your garden or patio if you build a rear extension. Further, if your neighbours aren’t consulted, the design or size of the extension could cause conflict between you and your neighbours.
Ensure neighbours are included in the design process to express any concerns concerning the proposed development. Before you apply for planning permission, you should sort out any problems before they file a complaint.

Can An Extension Be Avoided?

If you don’t wish to build an extension, you might consider turning an existing loft into another living space. In the same way, another option is to convert a current garage to increase your property value at a lower overall cost.

Need Of Planning Permission

Planning permission is the most critical part of any extension or building. If you do not take planning permission before starting work, it will result in the demolition of illegal property built and money loss. However, there are some exceptions when you do not need planning permission. you do not need planning permission if

  • There will be no commercial use of this property at all
  • Compared to the size of your house, the garage is half the size
  • If you live on the road, your garage won’t be in your front yard or on the side of your house
  • A height of no more than 4 metres
  • If at the rear of the house there is a road, the garage should be at least 3.5 metres away from it.

Converting the Garage

Once you know, What is the cost of extending over a garage? And factors to keep in mind are the extensions over garage; it is now time to focus on what should be made out of the extended garage and what you have to do for it. Consider the following essential points while converting a garage in any space

  • It is recommended that you replace the windows and doors
  • The damp-proofing must be assessed and, if necessary, updated.
  • Fix any wiring, plumbing, and drainage problems.
  • Walls and ceilings should be better insulated
  • Plasterboard should be used for the top and walls
Emmanuel Nwaebo

Emmanuel Nwaebo is the Managing Director at Powerpillar Ltd and has more than 25 years experience in building construction and renovations. He has a bachelor’s in Electronics and Electrical Engineering with certification in Construction Health and Safety Technician (CHST). With an experience in managing construction and renovation services for years, he is extremely passionate about property management and loves helping people find their dream property.

Get Your Quote Now


Powerpillar offers customised solutions tailored to meet the individual style preferences of its clients.

The Top 5 Benefits of Choosing a Custom Home Builder

Purchasing a home is usually one of the biggest investments for many people. There are two options when buying a new home for yourself and family. One is to buy a pre-built home, and the other is to purchase custom built house. Choose a custom home as it has many...

How a 3 Metre House Extension Creates Your Dream Cooking Space

Adding more living space to your home and increasing its value is a popular choice, and a home extension is a great way to accomplish this goal. Who wouldn't want more room to enjoy?  Are you tired of adjusting to a cramped kitchen, dreaming of a space where you can...

Top Bathroom Tile Trends in the UK for 2023

As we enter a new era of interior design, the bathroom serves as a blank canvas for expression and creativity. In the area of bathroom floor tiles, the United Kingdom experienced a stunning combination of classic beauty and nostalgic charm in 2023. This year's trends...

Integral Garage Conversion – An Ultimate Design and Cost Guide

Ever looked at your garage and thought, "Man, there should be a better use for this space?" Well, you are not alone. You have this integral garage, probably housing more dust than anything else. But hold on, there's a cool solution. You can go for an integral garage...

7 Brilliant Benefits of Glass House Extensions

Imagine sitting at a table, finding inspiration to write a new song, and amid the struggle, a bird flies by and gives you thousands of words. Imagine being a nature lover and wanting to spend time outdoors without going out. It might seem delusional at first, but let...

What size extension can i build without planning permission

Building extensions to your property can be an exciting prospect, offering additional living space, increased functionality, and potential value appreciation. However, the process of obtaining planning permission can be time-consuming and costly.  Luckily, in the UK,...

Under Garden Basement

Are you dreaming of expanding your living space without sacrificing your beautiful garden? Well, we have some exciting news for you! You can now build an under garden basement extension right under your garden! In this article, we'll walk you through the entire...

Basement Conversions in London

A basement conversion is a process of transforming the often-underutilised space beneath your property into a functional and habitable area.  This step-by-step guide explores the advantages of basement conversions, how to build a basement, all tailored to adhere to...