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in 2026 will I need planning permission for my extension Project?

Short answer: Most single-storey extensions in 2026 do not require full planning permission – as long as they meet the UK’s Permitted Development (PD) rules. But if your design is too large, too tall, in a restricted area, or connects to an older extension, you may need Prior Approval or Full Planning Permission instead.

This guide lays out the rules simply. It includes real homeowner scenarios, so you’ll know where you stand before starting your project.

1. First: How Planning Permission Actually Works in 2026

Before we dive into the rules, let’s break down the three types of permissions in the UK.

A) Permitted Development (PD)

✔ No full planning required

✔ Fastest, simplest route

✔ Works for most single-storey extensions

✔ Still requires Building Regulations

PD is what most customers use their projects.

If you stay within PD limits, you skip the planning process entirely.

B) Prior Approval (Larger Home Extension Scheme)

A halfway step between PD and full planning.

✔ Needed only when depth is:

• 6m on semis/terraces

• 8m on detached

The council checks impact on neighbours but the process is much lighter than full planning.

C) Full Planning Permission

Required when:

• You exceed PD limits.

• You live in a conservation area / AONB / listed building.

• PD rights are removed (common on new-build estates)

• You want a more complex or taller design.

• You link onto an existing extension and exceed the limits.

This is the slowest route – but sometimes is essential.

2. The Permitted Development Rules Explained (Simple + Visual)

These are the rules most homeowners fall under.

✔ How far you can extend (projection depth)

• Detached home: up to 8m (via Prior Approval)

• Semi-detached / terrace: up to 6m

Without Prior Approval:

• Detached = 4m

• Semi/terrace = 3m

Important detail most people miss:

Projection is always measured from the “original rear wall” of the house — not the current one.

This means:

• Bay windows count as part of the “original” wall.

• Previous extensions push the measurement forward.

• L-shaped houses measure from the furthest rear point.

This detail changes everything for some projects.

If the back of your house isn’t in a straight line and has “steps,” each step counts as part of the original rear wall.
This means you measure your extension from the part you are building from, as long as none of the new walls go beyond the permitted depth.

In the example below a semi-detached house can extend 3m from the original rear wall.

✔ Height rules (simple version)

• Max eaves height: 3m if within 2m of a boundary

What “Eaves Height” Actually Means (Clear Definition)

To avoid confusion, here’s the exact definition:

The eaves are the point where the wall of your extension meets the lowest part of the roof.

In even simpler terms:

👉 Eaves height = the height of the wall before the roof begins.

• Max overall height:

  • 4m (dual pitch)

  • 3m (flat roof)

• Cannot be taller than your house

The same approach is taken for flat roofs.

✔ Width and placement

• You can’t extend beyond half the width of the original house

• You cannot extend forward of the main elevation.

✔ Roof types allowed under PD

All of these can be PD:

• Glass roof = Conservatory

• Flat roof = Orangery

• Tiled roof = Extension

As long as the design stays within the PD limitations.

✔ Materials

Must be “similar in appearance” to the main house.

We achieve this with:

• Matching brickwork

• Matching render

• Same colour schemes

• Heritage detailing

This is why Precision designs look “natural” – and why they often fall comfortably under PD.

3. When You NEED Full Planning Permission

Full planning is required if:

• You live in a conservation area.

• Your home is listed.

• PD rights have been removed (common on estates built after 2010).

• Your design is too deep or too tall.

• You want to build on the side or front.

• Roof height exceeds PD.

• You’re creating a balcony or raised platform.

• You connect your new extension to an existing one and go over the combined limits..

Linking to an older extension often leads to planning issues. The council views the whole structure as one extension.

We take care of this during the design stage, so customers don’t make wrong assumptions.

4. The Most Common Misconceptions (Homeowners Get These Wrong)

This is the section that sets your guide above everyone else’s.

❌ 1. “If my neighbour objects, my project will be refused.”

False.

A neighbour objection only matters if it raises a valid planning concern, such as:

• Loss of light

• Overlooking

• Overshadowing

“I don’t like it” is NOT a planning reason. Your project can still be approved.

❌ 2. “If I change the design of my conservatory, I need planning.”

Not usually.

Changing:

• Doors

• Frame colour

• Layout

• Windows

…does not trigger planning as long as the conservatory stays within existing PD limits.

❌ 3. “Changing my conservatory roof always needs planning.”

Not always.

✔ Replacing a glass/poly roof with another?

Usually no planning.

✔ Changing to a tiled roof?

Often PD-compliant as long as:

• Height doesn’t increase

• Eaves remain compliant

This is why most tiled-roof upgrades we design do not need planning.

✔ Planning IS needed when the new roof goes outside PD limits.

👉 It’s not the fact that the roof is tiled – it’s whether the new design breaches PD.

✔ Regardless of planning, Building Regulations are ALWAYS required

This applies to every solid roof, because:

• The structure must support the extra weight

• A thermal assessment may be needed.

• Ventilation must comply.

• Structural calculations are required.

So the simple rule is:

👉 Planning depends on PD limits. Building Regulations are required every time.

❌ 4. “Orangeries need planning but conservatories don’t.”

False. The product type doesn’t matter – only the rules.

A small orangery may be PD. A tall conservatory might need planning.

❌ 5. “You can’t extend a listed building.”

You can – but you need Listed Building Consent.

Councils prefer:

• Timber

• Slimline profiles

• Heritage glass

But in 2025/2026 we are seeing more conservation departments approving aluminium when the design is sympathetic.

❌ 6. “If there was a conservatory here before, I can rebuild without planning.”

Not always.

If the old structure:

• Exceeded PD.

• Was built illegally.

• Was part of a previous extension.

• Changed the rear elevation layout.

…then you may need planning to replace it.

We check this during survey.

❌ 7. “If it’s PD, I don’t need building regulations.”

Incorrect.

Building Regulations apply to:

• Tiled roofs.

• Structural knock-throughs.

PD = removes planning

Building regs = safety & compliance

5. Does Linking to an Existing Extension Require Planning?

Often yes.

Here’s the simple rule:

✔ If your new extension connects to an old extension and the combined depth exceeds PD limits

→ Planning is needed.

✔ If the old extension already used up your PD rights

→ Planning is needed.

This is one of the biggest mistakes budget builders make – they ignore this rule entirely.

6. Real-World Scenarios 

Scenario 1 — 4m Orangery on a Semi

✔ PD compliant ✔ No planning ✔ Building regs required

Scenario 2 — 7m Orangery on a Detached Home

✔ Needs Prior Approval ✔ No full planning

Scenario 3 — 4m Orangery on a Detached Home with Internal Wall Removal

✔ PD compliant ✔ No planning ✔ Building regs required

Scenario 4 — Replacing Old Conservatory With Tiled Roof Extension

✔ Often PD if height remains the same ✘ Planning if roof height increases ✔ Building regs required

Scenario 5 — Extension on a New-Build Estate

✘ PD often removed by developer ✔ Planning required ✔ Building regs required

7. Certificate of Lawfulness — Should You Get One?

At Precision, we don’t routinely apply for Certificates of Lawfulness unless:

• The homeowner requests it.

• PD limits are tight.

• Proving legality will help with future sale.

• The property is in a sensitive area.

It is optional. Not essential. But helpful for peace of mind.

8. How Precision Confirms Whether You Need Planning

We make the planning route clear from the very start so there are no surprises later.

Step 1 — Site Survey

We take accurate measurements. Check boundaries. Assess the existing structure.

Step 2 — Initial Planning Guidance

We explain whether your project is likely to fall under:

• Permitted Development

• Prior Approval

• Full Planning Permission

So you know the route before any design work begins.

Step 3 — PD / Planning Check Before Quoting

Before we quote, we run a full check against PD rules and planning requirements. This ensures your quote is correct and you know what permissions you need.

We will take care of all the permissions for you = remove the hassle.

Step 4 — Structural & Building Reg Design (If Required)

We handle all structural and Building Regulations design as needed. This gives you a specification that’s compliant and ready for your project.

Want the full breakdown of what happens next?

We’ve created a step-by-step guide that shows you exactly what happens after this stage – from planning checks to foundations, frames, roof installation and final sign-off.

👉 Read the full step-by-step build timeline here

If you’ve ever stepped into an older conservatory, you’ll know the problem. Boiling hot in summer, freezing cold in winter.

That’s not because conservatories can’t be comfortable. It’s because of the glass.

Modern active glass has completely changed how conservatories, orangeries, and glazed extensions perform. It reflects heat, retains warmth, reduces glare, and even cleans itself. Changing a room that was originally seasonal into a space that functions throughout the year.

Let’s break down what makes it different, and why the right tint can make all the difference.

1. What is Active Glass?

Active glass is high-performance glazing that reacts to the environment around it. A microscopic coating on the glass surface:

• Reflects solar heat in the summer
• Retains warmth in winter
• Reduces glare from direct sunlight
• Self-cleans using UV light and rainwater

So, while traditional glass simply lets the sun in, active glass manages it. Helping maintain a stable, comfortable temperature all year round.

🌡 Think of it as intelligent glass – it adapts to the weather instead of fighting against it.

2. The Real-World Difference

Most of the heat gain or loss in a conservatory happens through the roof and glazing. That’s why choosing the right glass is far more important than adding extra square footage or fancy features.

💡 Precision Tip: It’s smarter to invest in a high-quality roof system with active glass. This is better than building a bigger structure with cheaper, standard glazing.

Every day, we notice homeowners who focus on size or extras. They often get a beautiful space that feels unliveable for half the year.

That’s why most customers choose Active Solar Glass. They want a true home extension, not a pretty but unusable space.

3. Understanding Glass Tints – Which one is Right for you

Different tints don’t only change the look of your roof – they change how it performs.

Here’s how the most common options compare:

🎯 Our Recommendation:

Active Blue remains the standout performer. It provides great heat control, natural light, and visual comfort. That’s why most Precision customers select it for conservatories and orangeries.

 4. Does Active Glass Make the Room Darker?

We know what you might be thinking:

“If the glass is blue tinted does that mean less light or a blue glow inside?”

It’s a great question, and one we hear all the time.

The answer is no – Active Blue and Neutral glass still let in plenty of natural daylight.

They filter harsh sunlight but don’t block brightness.

You’ll see a gentle tone when you look through the glass. Inside, your room stays open, bright, and airy. There’s no glare or “greenhouse” effect like with old polycarbonate roofs.

That balance is about Light Transmission. It measures how much light goes through glass. Too much light can cause glare, making a room uncomfortable. Too little light can make it feel dull. Active Blue glass does it well. It lets in the perfect amount of natural light, creating a bright and comfy space all year.

☀️ In fact, many of our customers comment that their new space actually feels lighter. The glass spreads light evenly in the room. This stops direct sunlight from causing hot spots.

5. Understanding U-Values (In Simple Terms)

You’ll often hear the term U-Value when looking at glass, roofs, and insulation. But what does it mean?

In simple terms:

A U-Value measures how well a material keeps heat in. The lower the U-Value, the better the insulation.

For example:

• Older glass roofs might have a U-Value around 2.7 W/m²K (lots of heat loss).
• Modern Active Blue glass is around 1.0–1.2 W/m²K, keeping warmth in during winter.
• A solid tiled roof can be as low as 0.12 W/m²K – about the same as your house roof.

💡 Think of it like golf – the lower your score, the better.

That’s why the right glass matters. Even if two roofs seem alike, the one with a better U-Value will stay warmer. It will cost less to heat and feel more comfortable throughout the year.

6. The Self-Cleaning Effect

It’s a small detail, but it makes a big difference long term. Plus, most customers do want to spend every weekend cleaning their glass roof.

The outer coating of active glass breaks down dirt using UV light and allows rainwater to wash it away evenly – meaning fewer streaks and less maintenance.

7. Real Proof From our Projects

Every time we install a conservatory or orangery with Active Blue glass, the feedback is consistent:

“It’s warm in winter, cool in summer. We actually use it every day.”

The temperature stability, glare reduction, and light tone make it the top choice for all our customers.

Check out this example

Once you’ve signed your order, the excitement begins. But you need to know – what happens next?

At Precision, we believe the process should feel clear and predictable from the very start.
That’s why we’ve laid out every step below. Showing who does what. When it happens, and what you can expect along the way.

We want you to feel fully in control of the process.

🧾 1. Order Confirmation & Welcome Pack (Days 1-2)

Once your order is confirmed and deposit paid, you’ll receive a set of emails to get everything started:.

• Your Order Confirmation – confirming your chosen specification and design.
• Project Manager Intro + Process Outline – our project manager introduces themselves and an email version of this blog on the process.
• Charity Selection Email – so you can pick which charity we donate to on your behalf.
• Your Agreement – the signed contract via your phone or computer.

💡Precision Tip: Save these emails. They contain your project reference, agreed specification, and payment details.

📏 2. Survey Visit (Week 1-2)

Our appointed surveyor will arrange a visit.

They’ll take final measurements and confirm every important detail with you.

During the visit, we’ll:

• Check ground levels, walls, and drainage.
• Confirm door and window openings.
• Review any changes or additions since the original quote.
• Run through any final questions

Once complete, you’ll receive a survey confirmation summarising everything agreed.

🧱 Precision Promise: Any adjustments discussed on site are always confirmed in writing, so there are no surprises later.

🏛️ 3. Planning or Building Regulation Approvals (If Required)

Not every project needs formal approval. But if yours does, we’ll manage it for you.

We’ll prepare and submit the necessary drawings and liaise with the relevant authorities on your behalf.

You’ll be kept informed throughout the process and notified as soon as approval is granted.

⚠️ Important: Your 6–8 week production timeline begins after approvals are granted, not after the order date. This ensures everything built on site complies with the final approved plans. 

Ensuring complete peace of mind.

⚙️ 4. Manufacturing & Scheduling (Weeks 3-6)

Once the survey is complete (and approvals confirmed if needed), your project moves into production.

We send all verified measurements and specifications to the manufacturer, who begins creating your frames, roof and glazing.

Meanwhile, our office team:

• Books your installation slot on the build schedule.
• Prepares your Payment Schedule so you can plan upcoming stage payments.
• Confirms your Frame Balance payment before delivery.

📦 When the frames and roof are ready, we’ll confirm the delivery date with you and ensure a Precision representative is on-site to accept it.

🔨 5. Installation (Weeks 6+)

On your scheduled start date, the build team arrives on site to begin work

The installation follows a clear order:

1. Groundworks and base construction
   
2. Frame and roof installation
   
3. Plastering, electrics, and finishing touches

Your Project Manager stays in contact throughout the build to keep everything running smoothly and on time.

🧱 Typical build duration: Most installations take around 4-6 weeks once on site, depending on design and weather conditions.

🪟 6. Final Steps & Handover

Once your new space is complete we ensure every detail meets Precision’s standards.

You’ll then receive:

• Your handover pack, including warranty and care information.
• Your final invoice, issued only once the work is complete and approved.
• Final photos for your finished project..

🎉 Your new space is now ready for decoration and furnishing. A bright, warm, functional room built to last.

🧰  7. Aftercare & Support

Our service doesn’t end when the build does.

If you ever have a question about your warranty or need support with any aspect of the finished work, our aftercare team is here to help.

We’ll make sure any issues are resolved quickly and professionally, keeping your new space performing exactly as it should.

🛠️  The Precision Promise: On Time. On Budget. World-Class Service.
That’s our commitment from first visit to final sign-off.

One of the main buying decisions for any homeowner is simple: How do I get the most from my budget

We completely understand. In this industry, it’s no secret that prices can vary wildly. Some quotes are overinflated to cover sales commissions, while others look like a bargain until the work starts. Then quality and service are below your expectations.

That’s why it’s natural to ask: “What should I really expect to pay for a conservatory, orangery or tiled-roof extension in 2025?”

It’s a fair question. And it’s exactly why we created this guide. To give you an honest, up-to-date overview of real project costs, what affects them, and how to make sure your investment delivers genuine long-term value.

Below you’ll find transparent pricing, clear comparisons, and practical examples based on real Precision projects completed across England. 

1. Average 2025 Price Ranges

2. What Affects the Price

1. Size & Shape
   • The bigger the footprint, the more glass, roof sections and foundations are required. Larger Simple rectangular builds cost less than angled or complex footprints.
2. Roof Type
   • Glass roofs are generally cheaper than tiled roofs. Tiled or hybrid roofs provide superior insulation and noise reduction but do cost more.
3. Colours
   • White Frames: lower cost – will match with any existing house windows.
   • Coloured Frames: 10-20% higher.
     • Precision Tip: Most homeowners split the frame going colour out-white in. This reduces the cost of having a colour. The white inside makes it easier to match the inside furniture. 
4. Site Access & Groundworks
   • Restricted access, drainage issues or deeper footings increase labour and material costs.
5. Finishings & Interiors
   • Flooring, plastering, lighting and heating choices can vary a project by several thousand pounds.

3. Cost Breakdown by Example Project

3.1 Example 1 – Classic Conservatory (£16-18,000 inc VAT)

• 4 x 3 m Lean To style with  polycarbonate roof.
• White uPVC frames.
• Includes dwarf walls and electrics.

3.2 Example 2 – Modern Orangery (£40-55,000 inc VAT)

• 3.8 × 5 m brick-based Orangery with aluminium lantern.
• 2x Anthracite Aluminium BiFolding Doors.
• Includes planning permission, building regulations, brick pillars, internal house wall removal, plastering and electrics.

3.3 Example 3 – Tiled-Roof Extension (£45-55,000 inc VAT)

• 7.4 x 3 m solid-roof build with 2x sky vista glass units in the roof.
• White uPVC frames.
• Includes building regulations, take-down of the old conservatory,  internal house wall removal, plastering and electrics.

4. How to Keep Costs Under Control

1.  Design around how you’ll use the space
   • Start with function, not footprint. A slightly smaller, better-insulated build is often more usable and more cost-effective compared to a larger, colder one.
2. Be realistic about finishes
   •  Interior extras like flooring, lighting and plastering can add 10–20 % to a build. Decide early what’s essential and what can wait. That is how you stay on budget.
3. Combine materials intelligently
   •  Most Precision builds use aluminium for the doors (for strength and slim-frames) and uPVC for the main frame (for insulation and value). It’s a simple way to achieve a premium look without the full aluminium price tag.
4. Choose performance over size
   • A high-spec roof and glass package will do more for comfort and resale value than adding an extra half metre in length. Energy efficiency pays you back long after the build.
5. Fix your price properly
   • Look for a company that offers a fixed-price quote, not an “estimate.” It keeps accountability clear and prevents creeping extras once work starts.

5. What you actually get for your money

Price differences aren’t just about size. They are about specification and finish. Two extensions can look identical on paper but feel completely different once built.

Here is where the money really goes:

Precision Tip: Don’t just compare prices. Compare specification.
A £35,000 conservatory and a £35,000 tiled roof extension deliver very different outcomes in comfort, lifespan, and property value.

6. Which Structure delivers the best value for you?

Each structure has its own strengths. The “best” one depends on how you want to use the space and what look you’re aiming for.

Precision Insight:

If your budget allows, upgrading to an orangery or tiled roof system gives an extra level of insulation and usability all year round.

But don’t overlook a conservatory. With the right roof design, glazing, and heating setup, we can make it a bright, comfortable room that’s functional through every season.

6. Our Honest Summary

It’s easy to get lost in prices, styles, and technical terms — but every successful project comes down to three things:

1. Clarity at the start — fixed quotes, clear drawings, no assumptions.
2. Quality materials, chosen for purpose — not upsold for margin.
3. A company that delivers on its promises.

At Precision, every design is built on those principles.

Whether you choose a conservatory, orangery, or tiled roof extension, our job is to help you invest confidently. We want you to enjoy a finished space that feels like it’s always belonged to your home.

I met with a customer this week who asked a question we hear all the time:

“Is aluminium really worth the extra money compared with uPVC?”

It is a great question and got me thinking that he, like many homeowners, wasn’t sure what the real difference was beyond the colour or price tag.

So, if you’ve been wondering the same, here’s the simple truth. Both materials are excellent. The right choice depends on how you plan to use the space, what style you want, and how long you expect to stay in the home.

At Precision, we design in both systems, so here’s a transparent comparison to help you choose confidently.

1. Cost & value

In most cases, aluminium frames are around 20–40% more expensive than uPVC equivalents.

That’s because aluminium is stronger, requires more complex manufacturing, and offers slimmer frames.

However, cost isn’t everything.

• uPVC keeps the project budget lower while delivering great insulation.
  
• Aluminium costs more initially but offers a longer lifespan and higher resale appeal thanks to its modern look and build quality. 

💡 Precision Tip: For long-term homes or high-design projects, aluminium is often worth the investment. For classic conservatories or value-led builds, uPVC delivers unbeatable performance for the price.

2. Thermal Performance

Thermal efficiency has levelled out in recent years.

• uPVC is naturally more insulating, reducing heat transfer through the frame.
  
• Aluminium used to lag behind but now features advanced thermal breaks – hidden barriers that stop heat loss.

What is a thermal break?
A thermal break is a thin, non-metal layer (often made of plastic or resin) built inside the aluminium frame.
It separates the cold exterior metal from the warm interior, preventing heat from escaping and condensation from forming.
Think of it like a built-in insulator between the inside and outside of your window or door frame.

When paired with modern active glass or a tiled roof system, both achieve excellent year-round comfort.

Key point: The roof and glazing choice make more difference to warmth than the frame material alone.

3. Strength and Design Possibilities

Because it’s stronger, aluminium allows thinner frames and larger panes of glass without extra supports.

That’s why, on most projects featuring bifold or sliding doors, we’ll specify aluminium for the doors only. This allows the design to handle the size and movement safely and maintain slim sightlines.

The rest of the structure (apart from the roof) can often remain uPVC, keeping costs down and insulation high.

This hybrid approach delivers the best of both worlds: strong, stylish doors with an efficient, budget-friendly frame system.

However, if the goal is a fully contemporary look. Clean lines, minimal frame thickness, and matching colour throughout, then we’ll recommend going fully aluminium for a seamless aesthetic.

Precision Insight: Many customers choose aluminium doors with uPVC frames, but if your design focuses on symmetry or ultra-modern styling, a full aluminium system gives the sharpest finish.

4. Maintenance & Lifespan

Both materials are low-maintenance — no painting, no rusting, no warping.

Real-world view: We expect uPVC systems to last 25+ years and aluminium around 35+ years, depending on location and care.

5. Style & Colour Options

Both offer extensive customisation:

• Unlimited RAL colours on both aluminium and uPVC.

• uPVC can also achieve realistic woodgrain effects. Rosewood, Golden Oak, Irish Oak, and more.

• Aluminium provides a flawless, contemporary finish but cannot replicate woodgrain texture.

So, if you’re trying to match existing Rosewood windows, uPVC is ideal. If you’re after clean anthracite lines or dual-tone contrast, aluminium will look sharper.

5. Sustainability

Aluminium is one of the most recyclable materials on earth. It can be reused indefinitely without losing quality.

uPVC is also recyclable, though it slightly downgrades each time it’s reused.

Both materials are eco-friendly options when sourced responsibly and installed with energy-efficient glazing.

5. Quick Summary

Our Honest View

Every home and every homeowner is different. 

Aluminium offers strength, sharp lines, and a longer lifespan. uPVC offers warmth, flexibility, and the option to match existing finishes.

At Precision, we design in both materials because the best system is the one that fits your space, budget, and style not a one-size-fits-all answer.