
Single story side extensions: the ultimate guide for homeowners
Are you looking to enhance your home’s potential without the hassle of relocating? Single story side extensions are not only a cost effective way to create more space but also an excellent option for boosting your property’s value. There are many types of single story side extensions ideal for Essex homeowners seeking design solutions that add a wow factor to their homes. Whether it’s an open plan kitchen extension with an island facing the living room or a cosy snug room for unwinding after a long day, a side extension can truly transform your space.
- What is a Single Story Side Extension?
- Benefits of a Single Story Side Extension
- Creative Single Story Side Extension Design Ideas
- Important Factors to Plan Your Side Extension
- Choosing The Right Materials for Your Single Story Side Extension
- Let Us Help With Design Costs for Your Extension
- Why Kirkwood is The Right Choice For Your Home Extension
- Creating a Kitchen Thats The Heart of Your Home
- Frequently Asked Question
- Closing Thoughts on Single Story Side Extension Ideas
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What is a single story side extension?

A single story side extension involves building outwards from the side of your property, making use of underutilised space like driveways or side alleys. In some cases, these extensions can also replace existing garages or merge with them, in which case, potentially saving a small fortune on build costs.
For Essex homeowners, a single story side extension is a great alternative to moving, why?, well it gives you the extra space you need without the stress of relocating. Most of us spend so much time in the kitchen, dining and living areas which are usually separated. Adding space downstairs can open up opportunities to completely change how these rooms connect. Here at Kirkwood, we don’t just design the extension itself. If you want and if your budget allows, we can redesign the entire ground floor to create an open plan layout that transforms your home. We’ve often heard our customers say It’s like having a new house, but without having to move.
Key features:
Compliment existing architectural styles
Enhances internal space with vaulted ceilings
Cost-effective and quick to construct

Benefits of a single story side extension
Even the smallest of single story side extensions can make the ground floor feel significantly bigger. A single story side extension doesn’t just add square footage, it transforms how you use your home by creating a better flow. Whether it’s opening up the kitchen into an open-plan design or adding a utility room, the possibilities are endless. It’s not just about adding space, it’s about maximising how that space works for you. (As they say, it’s not the size that matters—it’s how you use it that counts!)
Increase property value
A well-designed side extension can add up to 20% to your property’s value, therefore, making it an excellent investment for the future. The money you spend on the extension basically goes from you bank into your property. So technically, your house extension isn't costing you a penny.
Quick Construction
A single story side extension is faster to build compared to larger-scale projects. This means less disruption to your daily life. The majority of the extension is constructed and made water tight before any knock throughs start. A work schedule should be included with the build contract given to you from the builder.
Energy Efficiency
If using proper insulation and modern materials, your side extension will help reduce energy costs and add comfort to your home.

Creative Single Story Side Extension design ideas
Let us share some ideas that got the approval from thousands of our customers in Essex.
Open-Plan Kitchen and Dining Area
An open-plan kitchen and dining area is a feature for a single story side extension that gets great feedback from homeowners in Essex. With the guidance of an architect, your home extension in Essex can combine your kitchen, dining and living spaces all in one. This layout not only maximises natural light but also enhances the flow and usability of your home. By incorporating energy-efficient extensions and maintaining a continuous colour scheme you make the place look a great deal bigger.
Utility Room
A utility room is a perfect add-on to any single story side extension It offers a dedicated area for laundry and extra storage. For many Essex homeowners, a utility room provides a way to keep main living areas clutter-free. It’s an ideal solution for integrating energy-efficient extensions into your home, with options for modern appliances that give your home the wow factor. Transforming unused spaces like side alleys into a utility room extension allows for tailored designs, including a boot room or even a dog shower. By incorporating smart storage and creative side extension ideas, you can maximize space while boosting property value.
Home Office
A home office within your single story side extension is perfect for Essex homeowners balancing remote work. When designed by an architect, this space can provide the quiet environment needed for productivity. Clever storage can be incorporated along with a solution for bringing in natural light,. A home extension in Essex could solve your home workspace needs while adding value to your home.
Structural Planning for Single Story Side Home Extensions
When planning a single story home extension there are a number of things to consider to ensure a succeful outcome. These considerations can make a huge difference in achieving the best results for your extension and not to be overlooked. There have been countless times where home owners in Essex have had to demolish their home extension and star again, all because of not following the right steps. You can find out more on the importance of this here
Foundation Depth for Single Story Side Extensions
Foundations might not be the first thing you think about when planning a single story side extension, but they are one of the most important elements. They provide the essential base that supports your entire structure. If the foundation depth is incorrect, it could lead to serious issues for the rest of your home. The last thing you want is to be told that your new completed single story side extension needs to be underpinned or even worse, taken down!
The required depth varies depending on factors such as soil conditions and your existing property. For homeowners in Essex, where soil quality can differ greatly, working with an experienced architect is essential to ensure your single story side extension has a stable foundation that will be approved by building regulations and has been calculated by a structural engineer. It is important to highlight that a structural engineer is the only person qualified to decide on what foundations will be acceptable for your single story house extension. An expert structural engineer and architect will guide you through the technical aspects, ensuring everything meets building regulations.

Important factors to plan your side extension
Planning a side extension involves more than just choosing the right design. It requires careful consideration of building regulations and budget to avoid delays or unexpected costs.
Planning permission
Planning permission may not be required for a single story side extension thanks to permitted development rights. These rights allow you to build without a formal application if the extension meets specific criteria, such as being single-storey, no taller than 4m and not exceeding half the width of the original house. However, certain properties like listed buildings or those in conservation areas are excluded. To ensure your extension is compliant, obtaining a lawful development certificate is recommended for all house extensions prior to starting the build.
Design & Layout
Designing the perfect single story side extension requires careful consideration. Many Essex homeowners opt for open-plan designs to create a connection between the kitchen and dining area. These layouts are tried and tested. The feedback we get means going open plan on your single story extension is a no brainer. Collaborating with an experienced architect ensures that your ideas are configured into the design. Exploring side extension ideas with an architect could be the making of your project, fail to plan, then you plan to fail.
Budgeting & Materials
Planning your single story side extension requires a realistic budget which is ideally highlighted to the architect before they start designing. Single story extension costs can vary so being transparent with a budget enables the architect to design an extension you can afford. Careful budgeting and material selection will ensure your single story side extension meets both your needs and your budget.

Choosing the right materials for your single story side extension
Roofing
Depending on whether you’re having a flat roof single story side extension or a pitched roof, the finished material will vary. Flat roofs typically use felt or EPDM, while a pitched roof single story side extension will usually feature tiles designed to match the existing house tiles. The architect will calculate how much of the roof space should include glass to ensure ample natural light flows into the extension.
Windows & Doors
Bi-folding doors are a popular choice but can significantly increase the cost of your single story side extension. For a more affordable alternative, patio doors are a great option and are available in nearly any colour imaginable. Roof windows now come with advanced features like electric opening, rain sensors, built-in blinds, and even solar power. Large flat roof windows for flat roof extensions can also be electric opening, providing a refreshing breeze during summer months. To save money, consider having just one or two electric-opening roof windows, designed to match the appearance of non-opening ones.
Sofit & Fascia
Soffits are often overlooked when it comes to colour choice, depth and material, but they play an important role in the overall look of your Essex home extension. Soffit materials can range widely, our personal favourite is a cedar finish combined with external spotlights for a modern and stylish touch. Since the soffit and fascia area is relatively small in terms of square metre coverage, upgrading to a premium material for a more contemporary finish typically doesn’t add a significant cost. For the impact it provides, it’s a smart choice for your single story side extension. An architect can often show you photos of similar home extensions they’ve designed to help you decide.

Let us help with design costs for your extension
The cost of a single story side extension depends on size and complexity. Here’s a guide:
- Small Extension (20m²): From £1,250.00 – £1,450.00
- Medium Extension (30m²): From £1,450.00 – £1,950.00
- Large Extension (50m²): From £1,850.00+
Kirkwood offers free Design cost estimates to help you budget.
Why Kirkwood is the right choice for your home extension
At Kirkwood, we offer a full-service solution for Essex homeowners. Our services include pretty much everything but heres a list of some:
- Architectural plans
- Structural calculations
- Planning permission
- Free build cost estimates
- Free 3D kitchen designs
Don't take our word for it
Enquire today
Get in touch with a member of our friendly team to find out more about our highly competitive prices. You can also get in touch should you have any questions about our range, prices, or any of our services. We look forward to hearing from you.

Creating a kitchen thats the heart of your home
Tip 1: Embrace open-plan living: Let an architect design you a single-story side extension to create an open-plan kitchen that connects with the dining and living areas. This layout fosters better flow and makes the space feel larger and more welcoming.
Tip 2: Maximise natural light Your architect will design the extension In a way that allows enough natural light in but also not too much. The architect will also take into consideration of how to control the extra light and heat in the winter months
Tip 3: Kitchen island positioning If you have your hob in your island facing the living room you’re facing the family while you’re cooking. Much better than having your back to everyone, unless you prefer being in your zone. For suppliers we recommend Howdens
Areas We Cover in Essex
We proudly serve these areas in Essex for Architectural design:
- Chelmsford
- Rochford
- Harlow
- Basildon
- Billericay
- Brentwood
- Southend-on-Sea
- Wickford
- Rayleigh
- Benfleet
- Maldon
- Thurrock
- Braintree
- Colchester
- Leigh-on-sea
- Hornchurch
- South Woodham
Wherever you are in Essex, Kirkwood is here to help.
frequently asked question
The timeline usually ranges from 3 to 6 months, depending on factors such as project complexity and weather conditions.
Most extensions are covered under permitted development; however, some may still require planning permission. Even when an extension qualifies under PD rules, we obtain permission for your peace of mind.
Take advantage of our Howdens kitchen trade account to purchase a stunning kitchen at a fraction of the cost. Kirkwood also offers free build cost estimates to help you plan your budget effectively.
A well-designed single-story side extension can increase your property’s value by 5-20%.
t starts with planning and permissions, followed by construction and finishing. Kirkwood handles everything from start to finish.