Ignore these 12 red flags at your peril if you're on the hunt for the perfect plot

Let’s be honest – finding the 'perfect plot' is tough. With so few genuinely ideal sites out there, it’s no wonder self builders sometimes start looking at land that’s, well…a bit questionable.

When you’re eager to get your project moving, even a marginal plot can start to look attractive. But buying land to build on without really understanding what you’re getting into can be a serious risk. Just because a plot looks promising doesn’t mean you’ll ever get planning permission. In fact, some plots, no matter how lovely they appear, are almost certainly never going to get the green light.

To help you avoid a dead duck, here are a few major red flags that should make you pause – and probably walk away.

1. Plots without planning permission

Buying a plot without planning permission is one of the most common and costly mistakes self-builders make. Land might seem cheap, but without planning consent, you’ll have no assurances that it’ll be developable.

Sellers may offer verbal assurances that permission is ‘likely’ or a plot was granted permission nearby, but unless the land has detailed or outline planning permission confirmed, there are no guarantees.

The National Planning Policy Framework (NPPF) sets out strict criteria about what kind of development is allowed. Even if the site is an infill plot, or sits within a built-up area, there could be constraints like flood risk, or concerns that what you want to build will cause harm. Engaging with a planning professional before purchase is vital. They’ll check local planning policies, review any constraints and research previous applications to ensure an application is successful.

2. Plots with expired or expiring planning permission

A plot that once had planning permission might appear less risky, but lapsed or soon to-lapse permissions can be just as problematic. Extending a permission that’s about to expire isn’t allowed, so you’ll need to submit a brand new application. This means the plot will be exposed to whatever policy changes may have occurred since the original consent was granted.

This is especially risky for permissions that were heavily contested and only granted after an appeal. What succeeded once might not succeed again, especially if the local authority has changed their policies. A previously approved design might now be considered out of character, too dense, or unsustainable.

If the seller claims that the development has been commenced and the permission secured in perpetuity, check that this has been formally accepted by the local authority. If the work done did not meet the legal threshold, consent will have lapsed, no matter what assurances are offered.

3. Plots with restrictive covenants

Restrictive covenants are legal obligations that 'run with the land' and can severely restrict how it’s used. A covenant might prohibit residential development altogether, limit the type of buildings, or control design features like roof heights or the position of windows. Some even specify that only one dwelling may be built, which can prevent subdivision, unless the covenant is lifted.

Unlike planning conditions, covenants are not enforced by the council but by the individual or entity that benefits from them. Even if a restriction seems out of date, they can’t be ignored. The only way to remove or vary a covenant, is by agreement with the beneficiary, through a time-consuming and expensive legal process. It’s quite common for beneficiaries to use their covenant as leverage to demand a significant payment to release the restriction. So, watch out for what’s known as a 'covenant ransom.'

4. Plots with access issues

A legal right of access is fundamental to a development, but it can be overlooked when buying land. If the plot doesn’t have its own direct access to an adopted highway, you must verify that there’s a legal, right of access over any private land or shared drives. Just because there’s a physical road or track doesn’t mean you’ll have a legal right to use it.

Some plots are affected by ‘ransom strips’ – narrow pieces of land deliberately retained by previous owners that legally control access. Since the early 60’s there’s been a precedent that states that the owner of a ransom strip can claim up to a third of the plot’s enhanced value. This means the owner could demand a huge sum just to let you access your site.

Always ask a conveyancing solicitor to check access rights and make sure that these are registered on the title deeds. Also check for any third-party rights, shared drive agreements, or conditions tied to private roads that could prevent construction vehicles from gaining access to the build.

5. Plots with severe ground issues

Ground conditions can make or break a development and plots with contaminated land, poor geology, or historical industrial use can cost tens or even hundreds of thousands to clean up. A site might look lush and green but may once have been used as a petrol station or even for landfill.

Asbestos, rubbish, buried tanks, or oil spills may not be visible, but could render the site undevelopable without significant remediation. This means that invasive ground investigations are often necessary, to check for hazardous waste, and expensive specialist engineered foundations for difficult sites, like piles or rafts, might reduce the value of the land.

No matter how good the location, always make an offer conditional on completing a ground investigation. And never assume that it’s 'just grassland' without having completed a professional site investigation.

6. Plots with service connection problems

Building a home is one thing, but for most of us, making it liveable requires connection to the grid.

Plots in remote locations may not have access to essential services like water and electricity. Even in semi-urban locations, the cost of getting services to the site can be significant – especially where they need to be laid across main roads and closures are needed. Off-grid solutions like boreholes or solar-battery systems sound great, but they don’t have the appeal of a mains connection.

Never assume that services are close by and always ask for quotations, or commission utility searches, so connection costs can be fully allowed for.

7. Plots with legal disputes

Land embroiled in legal arguments is a headache and can seriously affect the future saleability of the finished home. Whether it’s a boundary dispute, contested title, or shared access issues, unresolved legal disputes can take years to resolve and may even need the courts to resolve them.

Disputes often don’t show up until late in the conveyancing process, or worse, might not be disclosed by the seller. Always ask a conveyancing solicitor to conduct full title checks, investigate any notices, and ask for the right disclosures to ensure there’s no unexpected legal complications.

8. Plots with unrealistic expectations

One of the most common traps, especially for first time self builders is buying with their heart, not their head. A rolling field with beautiful views might look amazing, but if it’s far from amenities, heavily sloped, it might be expensive to developable and therefore not viable.

Development viability is just as important as location. Construction costs are always rising, and build times often extend especially if you're not expertly organised. The danger is that you spend too much on the perfect plot, only to later find that the total cost of building a house exceeds its market value.

Always carry out a detailed financial appraisal with realistic assumptions on build costs and resale values and never buy land based on hope. Buy based on facts, policy, and proven feasibility.

9. Plots for sale on social media

The rise of unregulated marketplaces such as Facebook Marketplace or eBay, has created fertile ground for land scams.

These often feature attractive-looking plots for very low prices, with phrases like 'subject to consent' or 'perfect for development.' But, the reality is they have little to no chance of development.

Some plots are part of land banking schemes, where agricultural fields are split into small plots and marketed as investment opportunities, with next to no development potential. If the sales pitch creates artificial urgency – 'final bids by Friday,' or the seller discourages solicitor involvement, walk away – fast.

10. Plots on designated land

Building in designated areas, such as on plots within Areas of Outstanding Natural Beauty (AONBs), greenbelt land, or National Parks have strict planning controls. Even if a site contains an old barn or dilapidated building, development is not automatically permitted.

Class Q permitted development rights do not apply in AONBs or National Parks, which means barns in these areas are not eligible for agricultural-to-residential conversions.

Likewise, former dwellings that have been uninhabited for years may have lost their lawful use, especially if the building has fallen into disrepair. These become no more than follies in policy terms and can’t be redeveloped without full planning permission – which is unlikely to be granted in such sensitive locations.

11. Plots with severe risk of flood

The Environment Agency classifies land into Flood Zones 1 to 3, with Zone 3 being the highest risk. Plots in Zone 3 require a detailed Flood Risk Assessment and are often refused planning permission unless an 'Exception Test' is passed.

Building a house in a flood zone can result in complex designs like raised finished floor levels, or expensive flood resilience measures. Insurance may be costly as new homes don’t benefit from government schemes such as Flood Re.

Always check the Environment Agency’s flood maps to find out the flood designation of the land. If it’s in flood risk zone 2 or 3, then seek professional advice before going any further.

12. Plots with wayleaves or easements

Even when a plot appears clear, hidden infrastructure below ground can be the reason no one’s ever built on it.

Wayleaves or easements – which give utility providers rights to access and maintain their services – can effectively sterilise parts of the site.

Large sewers, high-pressure gas mains, or culverted watercourses are often impossible to move or prohibitively expensive to divert. You can’t build over these zones, so always request utility plans to check for infrastructure and if you find something, ask a solicitor to confirm whether its protected with a wayleave or easement.

Wondering if its time to go back to the drawing board? While heading to sites such as Plotfinder are a great way of sourcing land, check out the advice on other options to consider when finding a plot, and make sure your budget is realistic by understanding exactly what building plots cost.