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Can I Install uPVC Windows in a Conservation Area? (Hampshire Guide)
Can I Install uPVC Windows in a Conservation Area? (Hampshire Guide)
Category: Planning & Advice
Reading Time: 8 Minutes
📌 The Quick Answer
Can you fit uPVC in a Conservation Area? Yes, you often can, but you cannot use standard “bright white” plastic windows. You must use “Heritage” flush sash windows (like Residence 9) that replicate historic sightlines. Always check if your street has an “Article 4” direction first.
Many of us in Hampshire live in beautiful older homes. While these properties are full of character, they often come with single-glazed windows that are draughty, insecure, and expensive to heat. Replacing them is the obvious solution, but the phrase “Conservation Area” strikes fear into many homeowners.
The good news is that the rules have evolved. Planning authorities in Andover, Winchester, and Romsey are increasingly accepting of modern materials—provided the design is respectful.
Table of Contents
1. What is a Conservation Area?
A Conservation Area is an area of special architectural or historic interest. Unlike a Listed Building (which protects a specific structure), a Conservation Area protects the general “scene” of a neighborhood.
There are over 10,000 conservation areas in the UK. In Hampshire, they are managed by local councils (like Test Valley or Winchester City Council) to ensure that the character of our historic towns isn’t ruined by unsympathetic renovations.
In the 1980s, the double glazing industry earned a bad reputation for ripping out beautiful sash windows and replacing them with chunky, shiny white plastic. This caused significant harm to historic buildings.
As a result, many councils issued strict rules banning “plastic windows.” However, technology has moved on. Modern Heritage uPVC is now virtually indistinguishable from timber, leading to a relaxation of these rules.
2. Article 4 Directions Explained
Normally, changing windows falls under “Permitted Development” rights, meaning you don’t need planning permission. However, if you live in a Conservation Area, your council may have issued an Article 4 Direction.
Does every house in a Conservation Area have Article 4? No. It is specific to certain streets. You can check this on your local council’s website, or ask KJM to check for you.
3. The Dilemma: Repair vs. Replace
Before you decide to replace your windows, you must consider the condition of the originals. Planning officers will always prefer repair over replacement if the original windows are historically significant.
When to Repair:
- Historic Glass: If you have “Crown Glass” (glass with ripples/imperfections from before 1850), this is rare and valuable.
- Minor Rot: If only the cill is rotten, a timber specialist can often splice in new wood without removing the whole window.
When to Replace:
- Beyond Repair: If the frames are warped, allowing significant water ingress or rot that threatens the structure.
- Energy Efficiency: If the single glazing is causing condensation, mould, and unmanageable heating bills.
- Non-Original: If your home already has poor-quality windows from a 1980s renovation, replacing them with high-quality heritage replicas is seen as an “enhancement” by planners.
4. Timber vs. Heritage uPVC
Many homeowners assume they must use timber. While we install beautiful hardwood windows, many planners now accept Residence 9 (uPVC) as a valid alternative.
| Feature | Timber | Heritage uPVC (R9) |
|---|---|---|
| Appearance | 100% Authentic | 99% Authentic (Mechanical Joints) |
| Maintenance | Requires painting every 5-7 years | Virtually Maintenance Free |
| Cost | High (££££) | Medium-High (£££) |
| Lifespan | 50+ Years (if maintained) | 35+ Years |
| Planning Approval | Almost always approved | Frequently approved (Area dependent) |
5. The 3 Approved Solutions
At KJM, we have identified three routes that successfully gain approval in Hampshire conservation areas.
The Concept
A high-end composite uPVC system designed from the ground up to replicate 19th-century timber.
Why Planners Like It
It has a 100mm deep frame (matching old timber), mechanical joints (no ugly plastic welds), and a flush sash finish.
The Concept
The UK’s leading uPVC vertical sliding sash window, designed to replace draughty Victorian box sashes.
Why Planners Like It
It features “Run-through Sash Horns” and a super-slim meeting rail (35mm), keeping the glass area large and authentic.
The Concept
A discreet aluminium frame added to the inside of your existing window.
Why Planners Like It
It doesn’t touch the external fabric of the building. Usually requires NO planning permission.
6. How to Apply for Permission
If you do need planning permission, don’t panic. It is a standard process that KJM helps with regularly.
- Consultation: We visit your home to survey the existing windows and recommend the correct heritage replacement (e.g. Residence 9).
- Documentation: We provide technical drawings, cross-sections of the frame profiles, and photos of the proposed handles/hinges.
- Submission: You (or your agent) submit the application to the local council (e.g. Test Valley Borough Council).
- Decision: The process typically takes 8 weeks.
⛔ Warning: Listed Buildings
Conservation Area rules are different from Listed Building rules.
If your home is Grade II Listed, you cannot simply replace windows, even with timber replicas, without “Listed Building Consent.” This is much stricter than planning permission. In 90% of Listed Building cases, Secondary Glazing is the required solution.
For official guidance, you can read Historic England’s Guide to Upgrading Old Windows.
7. Frequently Asked Questions
It should have been flagged by your solicitor when you bought the home. If in doubt, check your local council’s website map, or give KJM a call—we know the local boundaries well!
Yes. We offer a wide range of high-performance timber windows and hardwood doors including Sapele hardwood, Oak, and Accoya. This includes stormproof window and traditional timber pulley-and-weight sash windows.
Absolutely. We have decades of experience working with local authorities in Andover, Winchester, and across Hampshire. We can provide the detailed cross-section drawings and specifications that planners require to make a decision.
📚 Explore Our Heritage Hub
Find the right solution for your period property:
Mark Pearce is a highly experienced specialist in the double glazing industry, having built his knowledge from the ground up through hands-on experience in installation, manufacturing, sales, and business management. Beyond his role at KJM, Mark is a keen blogger, writer, and traveller, often sharing insights on the latest innovations in the home improvement industry.
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