Conservatory vs Extension: Which Should You Choose for Your Home?

As your family grows or your lifestyle changes, you may find yourself wishing for a little more space at home. Moving house is one option, but with stamp duty, solicitor fees and moving costs to consider, many homeowners decide that improving their existing home makes more sense.

Two popular ways to add extra space are a conservatory and a single-storey extension.

Both can give you more room, but they differ in cost, installation time, planning requirements, energy efficiency and how the finished space feels. So, which one is right for your home?

At InWindows, we help homeowners explore these options every day. Here’s what you need to know before making your decision.

What Is a Conservatory?

A traditional conservatory is an addition to your home with a large proportion of its walls and roof made from glass or polycarbonate.

Modern conservatories are very different from the draughty, summer-only rooms of the past. Advances in double glazing, insulation and roof technology mean a well-designed conservatory can now be a comfortable space throughout much of the year.

Pros of a Conservatory

• Lots of natural light: Large areas of glazing create a bright space with great views of the garden.
• Generally more affordable: Conservatories are usually less expensive per square metre than a traditional extension.
• Quicker installation: Many conservatories use prefabricated frames, making them quicker to install than a full extension.
• Planning can be simpler: Depending on the design and your property, a conservatory may fall under Permitted Development rights.

Cons of a Conservatory

• Temperature can be an issue: Older conservatories can become hot in summer and cold in winter. Modern glazing and insulated roof systems can significantly improve this.
• Less privacy: Large areas of glass can make the room more visible to neighbours.
• Rain can be noisy: Heavy rain can sound louder on a glazed or polycarbonate roof than on a solid roof.

Best suited to: Garden lounges, dining areas, home offices, reading spaces and rooms where natural light is a priority.

What Is a Single-Storey Extension?

A single-storey extension is a permanent addition to your home, usually constructed using brick, blockwork or timber cladding to complement the existing property.

Unlike a traditional conservatory, an extension becomes part of the main structure of your home. This gives you greater flexibility over how the space is designed and used.

Pros of a Single-Storey Extension

• Feels like part of the house: A well-designed extension can create a seamless transition from your existing rooms into the new space.
• Good year-round comfort: Proper insulation and construction can provide excellent thermal and acoustic performance.
• Highly versatile: Solid walls give you more options for kitchens, bedrooms, utility rooms, offices and storage.
• Potential to add value: A well-designed extension can improve the appeal and value of a property, although the return depends on factors such as location, design and cost.

Cons of a Single-Storey Extension

• Higher upfront cost: Foundations, structural work, roofing and internal finishing can make an extension considerably more expensive.
• Longer project: An extension involves more planning and construction work, so it can take weeks or months to complete.
• More disruption: Expect more noise, dust and tradespeople on site during the build.
• Light needs planning: Unlike a conservatory, an extension doesn’t automatically provide lots of natural light. Skylights, roof lanterns and large glazed doors can help.

Best suited to: Open-plan kitchen-diners, utility rooms, extra bedrooms, home offices and larger family living spaces.

Conservatory vs Extension: Key Factors to Consider

So, how do the two options compare when you look at the factors that matter most?

1. Budget and Cost

For many homeowners, budget is one of the biggest considerations.

A modern uPVC or aluminium conservatory can often cost around £10,000 to £25,000, depending on its size, design, glazing and roof specification.

A single-storey brick extension is generally more expensive, with projects potentially starting around £30,000 to £50,000 or more. The final price depends on the size, foundations, structural work and what you want to include inside.

Adding a new kitchen, bathroom or extensive plumbing can increase the cost significantly.

It’s always worth getting quotes based on your specific project rather than relying solely on typical price ranges.

2. Planning Permission and Building Regulations

Planning requirements depend on your property and the size and design of the project.

Some conservatories can be built under Permitted Development rights if they meet the relevant conditions. In certain circumstances, they may also be exempt from Building Regulations, for example where the conservatory is separated from the house by external-quality doors and meets the relevant requirements.

Extensions are generally subject to Building Regulations, covering areas such as structural safety, insulation, ventilation and fire safety. Depending on the size and design, planning permission or prior approval may also be required.

If you’re unsure, check with your local authority or speak to a qualified professional before starting work.

3. Build Speed and Disruption

A traditional extension involves considerably more construction work. Foundations need to be prepared, walls built, structural openings created and the roof installed before the interior can be finished. This means the project can involve several trades and potentially weeks or months of work.

A conservatory is generally quicker to install, particularly when a prefabricated frame is used. Once the foundations and base are ready, the main structure can often be installed relatively quickly.

If keeping disruption to a minimum is important, this could make a conservatory an attractive option.

4. Thermal Performance

Older conservatories had a reputation for being too hot in summer and too cold in winter. Modern glazing, insulated frames, solar-control glass and improved roof systems have made a big difference. A well-designed conservatory can now be much more comfortable throughout the year.

However, a traditional extension can still offer excellent thermal and acoustic performance because it is designed and built as part of the main house.

The Middle Ground: Orangeries and Warm-Roof Conservatories

If neither option feels quite right, there are alternatives that sit somewhere between a conservatory and a traditional extension.

Orangeries

An orangery combines solid elements, such as brick pillars and a more substantial roof structure, with large areas of glazing.

This creates a room that can feel more like a natural part of the house while still benefiting from plenty of natural light.

Warm-Roof Conservatories

If you like the style and quicker installation of a conservatory but are concerned about temperature control, a warm-roof conservatory could be worth considering.

An insulated roof can improve thermal performance and give the room a more conventional, comfortable feel.

The roof system should be properly designed for the existing structure and comply with relevant building requirements.

Conservatory or Extension: Which Is Right for You?

There’s no single answer that works for every home. Your budget, available space, property and plans for the room should all play a part.

Choose a Conservatory If:

• You have a more limited budget.
• You want to create extra space relatively quickly.
• You enjoy natural light and views of the garden.
• You want a bright lounge, dining area or home office.
• You want to minimise major structural work.

Choose an Extension If:

• You want a larger kitchen-diner or open-plan living area.
• You need space for a utility room, bedroom or home office.
• You want the new room to feel fully integrated with the rest of your house.
• Thermal and acoustic performance are important priorities.
• You have the budget and time for a larger building project.

Ready to Create More Space in Your Home?

Whether you’re considering a modern conservatory, stylish orangery or full home extension, the right choice depends on how you want to use the space and what works best for your property.

At InWindow, we can help you explore different designs, glazing options, frames and roof systems to find a solution that suits your home.

Contact InWindows today to arrange a free home consultation and quote, and take the first step towards creating more space in your home.