10 Things to Check Before Buying a Building Plot

There's a particular kind of excitement that comes with finding "the plot", that patch of land where you can already picture the morning light hitting the kitchen, the way the garden might slope down towards the trees, the life you'll build there. We understand that feeling completely. It's the reason we do what we do.

But before you let yourself fall in love with a plot, there's groundwork to be done, literally and figuratively. A building plot is not just soil and boundaries; it's planning history, drainage, access rights, and a dozen quieter details that determine whether your dream home is a straightforward build or a five-year headache. Here's what we always tell people to check first.

1. Planning Status: What's Actually Been Approved?

A plot advertised as having "potential for development" is very different from one with detailed planning permission already granted. Check whether permission is outline or full, what conditions are attached, and whether it's still valid. Permissions typically lapse after three years if work hasn't started. Your local planning portal will have the full history, including any past refusals worth understanding. (For more on how planning works before you buy, see our [landowner's guide to garden development and Grey Belt policy].)

2. CIL and Developer Contributions

Before you get much further and commit to buying a building plot, check whether the Community Infrastructure Levy (CIL) applies to your local authority, and if so, what the rate is for your plot's location and size. This is a charge payable on most new dwellings, calculated per square metre, and it can run into tens of thousands of pounds (sometimes even hundreds of thousands) depending on the area. You may also be asked to make a Section 106 contribution towards local infrastructure such as schools or roads, particularly on larger sites. Self-builders can often claim a CIL exemption, but the paperwork must be submitted and approved before you start work, not after, so this is worth understanding early rather than discovering it as a surprise bill later.

3. Access Rights

Can you actually get to the plot, legally, not just physically? Check for a registered right of way if the plot doesn't front a public road, and confirm there are no restrictive covenants limiting how or when you can use an access route. A beautiful plot with no secured access is not a plot you can build on.

4. Services and Utilities

Is mains water, electricity, gas, and drainage already connected nearby, or will you need to bring services in from some distance away? This affects your budget significantly, sometimes by tens of thousands of pounds. Ask for utility company quotes before you commit, not after.

5. Ground Conditions

Soil type, contamination history, flood risk, and slope all shape your foundation costs and design options. A site survey and ground investigation report might feel like an unnecessary expense at this stage, but it's far cheaper than discovering unstable ground once you've exchanged contracts.

6. Flood Risk and Drainage

Check the Environment Agency's flood maps and ask about historic surface water issues on or near the site. Good drainage design is also central to biophilic, wellbeing-led building; a plot that manages water thoughtfully tends to make for a healthier, more resilient home.

7. Trees, Protected Features and Ecology

Mature trees are often part of what makes a plot beautiful, but they may come with Tree Preservation Orders, and the site itself might sit within a conservation area with its own design restrictions. This isn't necessarily a barrier; some of our favourite projects have been built around an existing tree rather than in spite of it, but it needs to be factored into your design from day one. Increasingly, plots also require a biodiversity net gain assessment, and protected species surveys for bats, newts, or nesting birds can affect timing and design. Building with nature rather than against it isn't just good practice for us at Millen; it's often now a planning requirement, so it's worth understanding early.

8. Boundaries and Ownership

Confirm the exact boundaries match what's registered with the Land Registry, and check for any shared ownership, easements, or ransom strips that could affect your plans. Boundary disputes are one of the most common, and most avoidable, sources of delay and cost.

9. Local Plan and Future Development

Look at your local authority's Local Plan to understand what's proposed for the surrounding area. A quiet field today could sit next to a new road or housing estate in five years. Understanding the wider context protects both your investment and your daily quality of life.

10. The True Cost of Buying a Building Plot

Finally, price the plot honestly against everything above: site preparation, utility connections, planning and professional fees, CIL and any developer contributions, and a contingency for the unexpected. The purchase price is only ever the starting figure. The real cost of a self-build only becomes clear once you've checked everything on this list.

We Do the Checking For You

The truth is, working through this list plot by plot can feel like a full-time job on top of everything else you're managing. It's exactly why we exist. We often have a selection of self-build plots available that have already been through this process, with planning status, access, ground conditions, and CIL liability all considered as part of how we bring them to market.

Take a look at our latest opportunities, or register your interest with us and we'll let you know as new plots come available.

A plot is the foundation of everything that follows, not just structurally, but for the way you'll live in the home you build on it. Taking the time to check these details properly isn't about slowing your dream down. It's about protecting it.

If you're weighing up a plot and want a second opinion, we're always happy to talk it through with you say hello@wearemillen.com