House Extensions

Experts In Adding Space & Value To Your Home

If you're thinking about getting an extension done, then getting a professional to do it should be the first thing on your list! Over the years we've worked on side, rear single and double extensions in South Wales, and one thing we can't stress enough is that if you don't use professional builders, you're going to see problems further down the road. So contact us today to get a full design and building service by our team to make your extension process as easy as possible.

Single, Double

Single, Double & Multi-Storey House Extensions beyond your expectations.

Side Return Extension

Create space in places you had written off.

Rear Extension

More room for the family.

Wrap Around

Make the most of you property and create added value.


Add some much needed light with a bespoke conservator/sunroom.

Porch Extension

Create some sophistication with an added entrance space.

Make An Enquiry Today

See the type of extension you want? Conact us today to
get your dream extension started!

Get a quote today
house extension and custom kitchen

Cardiff & South Wales House Extensions

The best house extension company in Cardiff & South Wales - contact us today to get your project underway. Still not convinced that you want an extension? Here's a few reasons just why you might!

  • Extensions add on average up to 20% more value to your property - as reported by Nationwide

  • Most of the time you don't need planning permission

  • Cheaper than moving home

  • More space for family & friends

Why You Should Choose Colsons Group For House Extensions

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We take immense pride in the work that we do and have always ensured that the work we've carried out is to the highest standard. Our previous work is enough to convince even the toughest of clients that we are the correct company to use for house extensions in Cardiff and South Wales.

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Throughout the construction phase we will consistently keep you up to date with the progress of the project. If you ever have any queries as to the development or if you need to make changes, our friendly team are always on hand to help.

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We work with you from beginning to end, this ensures that there's no unwanted surprises throughout the project and that you get the dream extension you deserve.

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No matter the design, we'll be able to create your desired space. We've worked on a range of extensions all within different material requirements and environmental needs and have always built the desired outcome.

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Built to last! Once work is completed you have our full guarantee on the build, giving you peace of mind in the knowledge that you're extension is there to stay - and with no unwanted dangers.

House Extension FAQ's

House Extensions, for a lot of people, take a lot of deliberation. From working out your budget, to figuring out the style and design you want - everybody is different in what they need/want. To make your life a little bit easier, we've created a section of FAQ's that we generally see when undertaking this work, just so you can be better equipped and understand the process that little bit easier.

Can All Properties Be Extended?

Whilst most properties can be extended, there are also a lot of other factors that come in to play and need to be considered. The main factor is space, and the amount you have of it available. It also comes down to the space along your house or in your garden. Then you need to consider your local regulatins from the council if they apply (in some cases you can go out and up to a certain distance. All of this can be looked at by our site surveyor who can figure out all of the restrictions (if any) that you may have.

What Can I Expect From Colsons Building House Extensions?

Expect proffesionality and proficiency. We've been doing this for decades and have dealt with every issue that could face us. We have a fully intergrated team that can plan, design and construct your house extension to your desired requirements. One of our directors is a RICS qualified QS who can fully cost and plan your project to make sure you have a clear understanding of the project from start to finish.

What Types Of House Extensions Are There?

There are a lot of house extensions you can get and we have the experience and expertise to meet all requirements. Each extension will be different and will depend on the layout, size and type of house you have. During our exploration meeting, we'll go through all the pros and cons with you of what would best fit your house. The main types of extensions can be found at the top of this page, they are; single,double and multi storey, side return, rear, wrap around and porch extension.

Do I Need Planning Permission?

Planning permission is typically not needed for house extensions as they come under 'permitted development rights'. This doesn't mean though that you can go ahead and built anything and everything you want as you'll need to submit plans as well as structural calculations all that will need to be submitted and need approval from local building control. Don't worry if this sounds intimidating, we can help you with every step of this process.

Do My Neighbours Need To Know?

If you have a party wall connecting your properties, then yes you'll need to let them know of the planned extension you're having. If they have an issue with this then you'll need to get a party wall surveyor to resolve the issue (we promise this isn't as complicated as it sounds and is typically resolved easily).

Do Colsons Have Any Accreditation?

Absolutely, we are proud membrs of RICS.

Do You Only Carry Out House Extensions In Cardiff?

Cardiff is where our head office and where typically most of our work comes from but we've worked hard over the years and are able to provide customers with a mobile fleet of profesional builders who can not only provide construction in Cardiff, but South Wales and the rest of the UK if the project is a good fit.

Contact Us For A House Extension Today

If you see a house extension service that you're in need of, feel free to fill out the below enquiry form for one of the Colsons Group team to get back to you ASAP. Whilst we're a Cardiff construction based company, we only use this as our head office area. In fact we'll take on building work across all of South Wales and the UK. We have a highly skilled workforce who are keen to meet new clients and take on any project. You can contact us by either calling or emailing us using the buttons below, or filling out an enquiry form further down to receive a quote within 24 hours.

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