House Extension Plans In London & South East

Extending your property is a cost-effective way of expanding your living space and increasing the value of your home. We have vast experience of carrying out extension drawings to a variety of classic and modern buildings. From your initial appointment, we will use your ideas to design a house extension optimising space and appearance of your home.

1. Design

Whether your family is growing, and you need an extra bedroom, or you want a new bright modern open plan living; we can help find a solution to maximise your space. Here at Detailed Planning, we have a team of trained designers that are specialised in creating amazing spaces for all types of briefs. We understand the cost of developing a property, so we’re sensitive to our costs and guidance. We aim to help you stretch your money enough to get the best results!

2. Get approved


Now it’s time to get that Planning Application sorted. Once the drawings have finalised they’ll head off to your local council. This can take up to 8 weeks for a decision and throughout we’ll be making sure everything is done to make it a smooth decision. You’ll be kept updated every step of the way... As we find out news, you will too! As you’ll have some spare time on your hands, why not check out some design inspiration for whatever your building? We have many examples of our work on our website if you’re stuck!

3. Technical

This is the stage where the detailed technical drawings are carried out by our design team. We believe in providing extra detail so your builder construction your project with the quality it deserves. Remember, in order for a project to go accordingly, having a good, detailed set of drawings is crucial.

4. Ready, Set, GO

At last! Your dream home is now ready to go under construction! This is all very exciting and you now have all the relevant drawings to hand. At this point of the project, we provide a continued support service, so feel free to call us whenever you like. All that’s left to do now is grab a cup of tea and relax!

Want to see a case study for one of our house extension projects? Click here


House Extension Plan Fees

For guidance only, for a single storey rear extension to a small property, our fees start from:

  • Design and Planning Application: £900+VAT
  • Technical Building Reg Drawings: £700+VAT
  • Site Measure (If required): £220+VAT


Read our blog posts 

Extension: A Beginner's Guide

Why Should You Extend Your Home? Building an extension to a house is an increasingly popular choice for homeowners seeking to maximize the potential from their property...

How To Chose A Builder

How to Choose a Builder... You’ve never had experience in the building trade and never developed a home. Even worse, you’ve watched too many programmes...

Have any questions? Read our FAQs below!
A Homeowners Guide and FAQs to Your Detailed Planning Project


Why Choose Us?

  • Affordable Prices
  • Fixed Fees
  • Quick Turnaround
  • Honest Advice From Your Dedicated Designer
  • Identifying Constraints & Design Opportunities

What Our Clients Say?

"We have worked with Detailed Planning on hundreds of projects and have always found them to be professional, reliable and the quality of their work is extremely high. This helps us greatly when undertaking the structural design work on their projects. I would highly recommend Detailed Planning to any clients who are looking for assistance with Architectural services."

Chris Porthouse - Porthouse Dean
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