Key Takeaway
A wave of government planning reforms is reshaping what's possible for homeowners across Hampshire, Surrey, Hertfordshire, Berkshire, Wiltshire, Oxfordshire and Buckinghamshire. If you've been thinking about extending, 2026 could be the most important year to act.
How do project costs and planning routes compare?
Extensions add to the building, while loft and garage conversions work with existing space; each has different structural and planning considerations. The route depends on the property, so these comparisons are not an individual planning decision or quotation.
| Project | Typically needs planning? | Main cost factors | Typical design route |
|---|---|---|---|
| Single-storey extension | May qualify for permitted development if all conditions apply | Footprint, foundations and specification | Survey, layout, planning check and technical drawings |
| Two-storey extension | Depends on the design and permitted development limits | Structure, roof design and specification | Survey, planning check and coordinated structural information |
| Loft conversion | Some roof works may qualify, subject to restrictions | Roof type, stairs and structural work | Roof and layout assessment, planning check and Building Regulations |
| Garage conversion | Often possible without a planning application, but exceptions apply | Insulation, structure and services | Survey, planning check and Building Regulations design |
If you've been thinking about extending your home, 2026 could be the most important year to act. A wave of government planning reforms is reshaping what's possible — and for homeowners across Hampshire, Surrey, Hertfordshire, Berkshire, Wiltshire, Oxfordshire and Buckinghamshire, the window of opportunity is wide open right now.
Have a project in mind? Start with a few details about your home.
Check your planning routeThe Planning System Is Changing — Here's What You Need to Know
The UK government has made no secret of its ambition to reform planning. With a housing crisis to address and a manifesto commitment to build 1.5 million new homes, ministers have introduced sweeping changes that affect not just developers and housebuilders — but ordinary homeowners wanting to extend.
Three changes in particular are worth understanding if you're considering a rear extension, loft conversion, side return, or garden room in the near future.
1. Grey Belt & Green Belt Reviews — A Once-in-a-Generation Opportunity
If you live in a Green Belt area and have previously been told an extension isn't possible — or were put off even trying — it's time to look again.
The government has released £14.8 + VAT million of funding to local authorities with Green Belt land, triggering a fresh round of Green Belt reviews across England. These reviews are identifying so-called "Grey Belt" land — under-performing Green Belt parcels that no longer justify their protected status — and releasing them for development.
For homeowners, this matters. Local planning policies that were once used to refuse householder applications in Green Belt areas are being reconsidered. Councils in Surrey, Hampshire and Berkshire — all counties where Hampshire Build operates — are among those affected.
If your home sits within or adjacent to Green Belt land, it is worth getting proper advice before assuming the answer is no. The rules may have changed since you last asked.
2. Local Plan Chaos — Why an Experienced Team Matters More Than Ever
Here's something that surprises many homeowners: planning decisions aren't just governed by national rules. They're also shaped by each council's Local Plan — a document that sets out local policies on design, density, extensions and more.
Right now, the Local Plan landscape is in turmoil.
East Hampshire District Council recently announced it is abandoning its Local Plan submission entirely, with its leader stating that repeated government interventions have made the work "pointless and unjustifiable." They are far from alone. Councils across the South of England are pausing, rewriting or delaying their Local Plans in response to the same wave of national reforms.
What does this mean for you? When a council lacks an up-to-date Local Plan, planning decisions become less predictable and more open to challenge. Applications that might have been straightforward can hit unexpected hurdles — and applications that might once have been refused can now succeed with the right approach.
This is exactly the environment where working with a practice that knows the local planning landscape pays dividends. Hampshire Build understands how each local authority thinks, what their officers look for, and how to present an application clearly.
3. Permitted Development Rights — Bigger Changes Are Coming
Permitted Development (PD) rights allow homeowners to extend their properties without submitting a full planning application — and they are about to get more generous.
A Permitted Development Rights (Extension) Bill is currently making its way through Parliament, with proposals to expand what homeowners can build without planning permission. The changes would allow larger extensions, more loft conversions and greater flexibility for outbuildings — provided building regulations are met.
Ready to apply these ideas to your own home?
Explore your planning optionsThe government has also been reviewing the 2024 consultation on PD reforms, with results expected to feed through into legislation during 2026 and 2027.
What this means in practice: homeowners who previously assumed they needed full planning permission for their project may soon discover they don't. But — and this is important — permitted development does not mean unregulated. Building regulations still apply in full. Structural calculations are still required. And for many projects, a Lawful Development Certificate is strongly advisable to protect your position when you come to sell.
In short: the planning hurdle may get lower, but the technical and building control work remains just as important.
What Should You Do Right Now?
The honest answer is: don't wait.
Planning reforms create opportunity — but they also create uncertainty. Councils are reviewing policies. Local Plans are being rewritten. What is straightforward today may become more complex tomorrow as new design codes and biodiversity net gain requirements bed in.
Buckinghamshire, for example, is due to publish its new Local Plan in summer 2026 — a plan that will set tighter design requirements for all new development in the county. Homeowners in Buckinghamshire who have been considering an extension would be wise to get their application submitted before those new rules take effect.
The same logic applies across our patch. Whether you're in Winchester or Woking, St Albans or Salisbury, Henley or High Wycombe — 2026 is a year to move forward, not sit on the fence.
How Hampshire Build Can Help
Hampshire Build is a fixed-fee residential design practice covering Hampshire, Surrey, Hertfordshire, Berkshire, Wiltshire, Oxfordshire and Buckinghamshire. Our packages include planning drawings and building regulation drawings prepared for Building Notice submission, with required structural calculations prepared by an independent qualified structural engineer. Premium adds defined contractor tender support.
All three packages include a measured survey, planning drawings and application submission, building regulation drawings prepared for Building Notice submission, and structural calculations prepared by an independent qualified structural engineer. Premium adds defined contractor tender support; Premium Plus also includes a staged programme and specified notices. Construction-phase services are not included.
The packages set out defined design and pre-construction services, with contractor involvement limited to the selected tender scope.
Ready to find out what's possible? Book a complimentary 30-minute call with Mark Eden, Founder of Hampshire Build, at calendly.com/mark-hampshirebuild/30min or call us on 01722 548911.
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