How to draw a site boundary for planning permission

One of the most important steps in preparing a planning application is drawing the site boundary correctly. In simple terms, you have to show the land your application actually relates to - clearly, accurately, and in the right place.

Show the main site’s boundary with a red line

Start by identifying the full area your proposal depends on. Then draw the red line around all of it - not just the house, extension, or building footprint, but the full planning site.

This is the primary boundary, and it should include all the land needed to carry out the proposed development. That might mean more than just the building or plot itself. For example, the red line may also need to include access from the public highway, parking areas, landscaping, visibility splays, or any other land that forms part of the proposal.  

Show other land that’s relevant with a blue line

If you own neighbouring land that touches or sits close to it, draw that separately in blue - this is a way of making it easy to recognise the site, ideally by showing two named roads, or one road name and a landmark if that is not possible. This is the secondary boundary. It doesn’t replace the red line, but it helps the planning authority understand wider ownership around the site. There may be no blue line, one blue line, or several, depending on the property and the application.  

Is it important to get these lines accurate?

Yes. If the red line is too tight, misses access land, or doesn’t reflect the actual proposal, then the application can be delayed or marked invalid. A planning boundary is there to show the true extent of the development site, not just the part that feels most obvious. Local authority validation checklists regularly flag missing or inconsistent red and blue lines as a common problem.  

If you want to make that process easier, then our MapShop can help you get the right planning map in the first place - and it provides easy-to-use drawing tools to mark those maps clearly and correctly.

How Emapsite can help

If you can't find exactly what you need, we can also help you choose the right mapping data solution for your project via email, chat or over the phone.

For more information, reach out to our Customer Support team.