Know your boundaries: navigating legal property issues in new developments

8 July 2025

5 min read

Understanding site boundaries is a critical component of property development. Whether you're planning a residential estate, commercial hub or infrastructure project, clearly defined boundaries are essential — not only for design and construction but also for avoiding legal disputes and ensuring smooth sales to purchasers and their lenders.

Below, Lisa Robotham and Amelia Hayden from our housing team set out what developers need to know about boundary issues — from spotting problems early to resolving disputes — so you can keep your project moving and stay legally compliant.

Why boundaries matter

Before you buy land or apply for planning permission, it’s crucial to understand the exact limits of your site. Overlooking boundary issues can cause costly delays, legal complications and even put future sales at risk. A well-defined boundary helps make sure you can build as planned and that your plots are mortgageable and ready for market.

How boundaries are identified in property law

In England and Wales, property boundaries are generally assumed to follow the red line shown on the title plan registered with HM Land Registry (HMLR). However, these plans are governed by the General Boundaries Rule, meaning the red line shown is indicative — not precise. Physical features like fences or hedges may not align perfectly with legal boundaries and encroachments from neighbouring properties may have occurred over time. The physical boundaries may therefore be quite different from those shown on the title plan.

Under section 60 of the Land Registration Act 2002, boundaries are not exact unless formally determined[1]. HMLR provides a process for applying for a boundary to be a “determined boundary” which may be appropriate if the neighbouring owner agrees to the boundary position, or to rely on a jointly appointed expert’s decision as to the boundary position. However, if neighbouring owners cannot agree the position of the boundary or the neighbouring owner’s land is unregistered, the process can be expensive and lengthy.

In some cases, established legal presumptions can help determine the position of a boundary where it isn’t clear from the deeds. For example, where two properties are divided by a hedge and a ditch or a bank and a ditch, there is a presumption that the boundary is along the opposite edge of the ditch from the hedge or bank. However, these legal presumptions can be rebutted, as was the case in Parmar and others v Upton [2015] EWCA Civ 795.

Practical steps for developers

Inspect the site: Before acquisition, inspect the site thoroughly and compare the boundaries to those shown on the title plan. Take photographs, note any discrepancies, and consider GPS mapping to overlay your proposed site plan with the title plan.
Instruct a surveyor: If acquiring part of a title or developing an estate, commission a qualified surveyor to produce an accurate plan. Ensure the surveyor has the title plan. A good surveyor will flag potential boundary issues early.
Get legal advice: Advise your solicitor immediately of any inconsistencies between physical boundaries and the “red line” title boundary. Ask your solicitor to conduct a SIM (Search of the Index Map) at HMLR. This reveals all registered titles within your proposed site and highlights any overlaps or encroachments.

Risks of ignoring boundary issues

Failing to address boundary discrepancies can have serious consequences:

Delays to sales: Purchasers’ solicitors may uncover issues that prevent completion. Lenders won’t finance plots with unresolved boundary concerns.
Planning and infrastructure complications: Your planning application may include land that is not in your legal ownership. Roads and sewers intended for adoption must lie within your title — encroachment could lead to redesigns or negotiations with neighbouring landowners.
Legal complications: On a purchase, registration of ownership will be suspended until the boundary issue is resolved. For development of new estates, HMLR estate layout approvals may be withheld or subsequently withdrawn resulting in delayed plots sales and inability to register plot transfers and mortgages. Boundary disputes can arise quickly and litigation for disputes can result in escalating costs.

Resolving boundary disputes

If you suspect a boundary issue:

Speak to a lawyer: Provide site photos and details. Your solicitor can run a SIM search and review title deeds for clarity.
Define your goal: Decide whether you want to reclaim land, adjust plans or negotiate with neighbours.
Consider practical solutions:
- Redraw plans: For minor encroachments, pursuing action may not be cost effective and adjusting your layout may be more appropriate.
- Sell or acquire land: If your land has been encroached upon, consider selling the affected strip to the neighbour. If you’re encroaching on the neighbour’, explore adverse possession claims or negotiate a boundary agreement.
- Boundary agreements: These can formalise arrangements and, as shown in White v Alder[2], bind future owners — even if they weren’t aware of the agreement.

Boundary issues are often complex and expensive to resolve. But tackling them early — with a mix of careful examination of boundaries on a site inspection, legal checks, and other expert input — can prevent problems down the line.

Know your boundaries, and you’ll give your development the best chance of success — from planning to completion