What Is a Single Storey Extension and Is It Right for Your Home?

If your home is starting to feel a little cramped, or you have always wished the kitchen was bigger, a single storey extension could be exactly what you are looking for. It is one of the most popular ways to add space, light, and genuine value to a property without the upheaval of moving house.

But is it the right option for your home? And what does the process actually involve from start to finish?

This guide covers everything you need to know, from the basics of what a single storey extension is, through to planning, costs, design ideas, and how to find the right house extension builders for the job.

What Is a Single Storey Extension?

A single storey extension is a ground-level addition to your home that extends the existing footprint of the building. It is typically built to the rear or side of a property, though wrap-around designs that combine both are increasingly popular with homeowners across Dorset and beyond.

Unlike a loft conversion or double-storey extension, a single storey extension stays at ground level. This makes it one of the more straightforward types of extension in terms of structural complexity, though that does not mean the planning and construction process should be taken lightly.

Single storey extensions are most commonly used to:

• Enlarge an existing kitchen or dining area
• Create an open-plan kitchen and living space
• Add a dedicated utility room or downstairs bathroom
• Extend a lounge or sitting room
• Build a light-filled garden room or orangery-style space

The versatility of this type of extension is a large part of why it remains so consistently in demand amongst homeowners looking for small home extension ideas that deliver real, everyday benefit.

Single Storey Extension vs Other Types of Extension

Before committing to any particular route, it helps to understand how a single storey extension compares to the alternatives.

Extension Type	Typical Use	Planning Required?	Relative Cost
Single storey rear extension	Kitchen, dining, living space	Often permitted development	Medium
Single storey side extension	Utility, hallway, garage conversion	Sometimes permitted development	Medium
Double storey extension	Bedroom, bathroom, office above	Usually requires planning	Higher
Wrap-around extension	Large open-plan living spaces	Usually requires planning	Higher
Loft conversion	Bedroom or office above	Often permitted development	Medium to high
Orangery or garden room	Relaxation, working from home	Often permitted development	Varies

As this table shows, a single storey extension often sits in a sweet spot. It offers a meaningful gain in living space at a more manageable cost than a double-storey build, and in many cases it can be completed without a formal planning application under permitted development rights.

Do You Need Planning Permission for a Single Storey Extension?

This is one of the first questions homeowners ask, and the answer is: not always.

In England, many single storey rear extensions can be built under permitted development rights, meaning you do not need to submit a full planning application. However, there are specific limits and conditions that apply, and working with experienced Dorset building services can help you understand these requirements before you begin.

Permitted Development Rules for Single Storey Extensions

Under current extension planning rules in the UK, a single storey rear extension may fall within permitted development if it meets the following criteria:

• It does not extend beyond the rear wall of the original house by more than 4 metres for a detached property, or 3 metres for any other type of house
• The height of the extension does not exceed 4 metres at its highest point
• The materials used are similar in appearance to those of the existing house
• It does not cover more than half the area of land around the original house

These are general guidelines and the specific rules can vary depending on your property type, location, and local authority. If your home is in a conservation area, is a listed building, or falls within the Dorset Area of Outstanding Natural Beauty, additional restrictions may apply.

For a rear extension in Dorset, especially a modern house extension, check with your local planning authority or a builder before assuming permitted development applies.

When a Full Planning Application Is Needed

You will likely need to submit a planning application if:

• Your extension exceeds the permitted development size limits
• Your property is listed or in a designated area
• You are planning a side extension that faces a highway
• You want to build a wrap-around extension combining rear and side additions
• Previous extensions have already used up your permitted development allowance

A good local building contractor will be able to advise you on this clearly from the outset, saving you time and potential complications further down the line.

Small Home Extension Ideas: Making the Most of the Space

One of the most exciting parts of planning a single storey extension is deciding how to use the new space. Here are some of the most popular approaches that homeowners across Dorset and the wider in UK are choosing right now.

Open-Plan Kitchen Extension

A popular choice that opens up the rear of the home to create a spacious kitchen and dining area. Large doors to the garden bring in natural light and enhance the overall feel.

Kitchen Extension with Roof Lantern

Ideal for flat or low roofs, roof lanterns or skylights add natural light, creating a bright and airy kitchen space.

Side Return Extension

Fills the unused side space of a property to expand ground-floor areas without reducing garden size. Common in terraced homes.

Utility Room or Garden Room Addition

Smaller extensions that add practical spaces like utility rooms or relaxing garden rooms, improving everyday living.

Wrap-Around Extension

Combines rear and side extensions to create a larger L-shaped space, offering a major transformation to the home layout.

How Long Does a Single Storey Extension Take to Build?

Again, this depends on the size and complexity of the project, but as a general guide:

• A small to medium single storey extension typically takes between 10 and 16 weeks from start to completion
• Larger or more complex builds may take 20 weeks or more
• The pre-build phase, including design, planning, and building regulations approval, can add several months before construction begins

Factor in lead times when planning your project. A good builder will provide a realistic timeline upfront and keep you updated throughout the build.

You can discuss your project requirements, gain further insight into the process, and learn more about the services provided for a wide range of residential and commercial projects.

Finding the Right House Extension Builders

Choosing the right builder is one of the most important decisions. A well-built extension adds value, while a poor one can lead to costly issues.

When selecting a builder in Dorset, consider:

• Local experience: Familiarity with local planning, materials, and property styles.
• Transparency: Clear, detailed quotes with no hidden costs.
• Communication: Regular updates and a responsive approach throughout.
• Craftsmanship: High-quality work that ensures durability and performance.
• References: Proven track record with positive client feedback.

Experienced, detail-focused builders are worth choosing, as quality work makes a lasting difference over time.

Rear Extension Dorset: What Local Homeowners Should Know

If you are planning a rear extension in Dorset, it is important to consider local factors. The county has a mix of property styles, from traditional cottages to modern homes, and each requires a different approach.

Many areas fall within conservation zones or protected landscapes, meaning extensions need careful design and planning approval.

Working with a local builder ensures better understanding of materials, planning requirements, and efficient project management using trusted local trades.

Conclusion

A single storey extension is a practical way to add space and improve your home, whether for a kitchen, living area, or extra room. Success comes down to proper planning and the right team. Understanding permissions, costs, and timelines helps make the process smoother.

For Dorset homeowners, working with a skilled local builder ensures quality results that add long-term value, not just extra space. Contact us today to discuss your extension plans and get expert advice from a trusted local builder in Dorset.

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