Duncan Thompson Extensions are specialist designers and builders of quality home extensions. Only a specialist extension company knows what your extension will cost to build and how long it will take to complete.

Custom Design

Design by definition is “The art or practice of designing and constructing buildings.” Importantly it is the style in which a building is designed or constructed, especially with regard to a specific period, place, or culture. There has and always will be good design and not so good. This is the same for house extension design.

Dedicated to great design

At Duncan Thompson Extensions we ensure our design not only delivers on your expectations, but also complements your home, with total consideration for your home’s period, place and culture.

Do I need an Designer to Design my Extension?

You do not need an Designer to design your home extension. An designer will design your extension based on your needs and wants, but they won’t know whether their design is accurate to your budget. They are not estimators. Because of this, an extension designed by an independent designer may exceed your budget dramatically, but you won’t know this until you’ve already paid all the designer fees and go searching for a builder. At Duncan Thompson Extensions you will have a accurate designs and a quote within weeks of the very first meeting.

Who do you talk to and where do you find the right people?

Anyone who’s built a house before understands that home builders have their own display homes for you to visit to get an idea of what they offer. Extension builders are different. An extension builder is a specialist at what they do, they build extensions, not houses. There are no places to go to see a range of different extensions on display. All their work is now a part of someone’s home, it’s attached. This can make choosing an extension builder a little more difficult.

Two important steps when planning a home extension


Only use a specialist extension builder

Only they have the experience required to properly and professionally build your extension. Only they have the people with the appropriate skills to build your extension. Their designers only design extensions. Their estimator only estimates extensions. Their trades people only build extensions. An designer doesn’t estimate or build and a builder without a design can’t estimate and build.


Only use a specialist extension builderOnly use a design & construction builder

Only deal with an extension builder that can design and construct home extensions. This is the only way to get value for money. All the necessary qualified people are situated within Duncan Thompson Extensions. You have no need to go anywhere else.