Double Storey Extensions: A Complete Guide

Are you finding your current home a bit of a squeeze? Perhaps a growing family has you dreaming of more bedrooms, or the desire for a spacious home office is becoming a necessity. Whatever your reasons, moving house isn’t the only option. Double storey extensions can be a truly transformative solution, adding significant living space and value to your property without the hassle and expense of relocating.

At Abbey Partnership, we specialise in creating beautiful, functional, and seamlessly integrated double storey extensions. We understand that undertaking a major home improvement project can be daunting, which is why we’ve created this comprehensive guide to walk you through everything you need to know.

What is a Double Storey Extension?

A double storey extension, as the name suggests, is an extension that adds space to your home on two levels: the ground floor and the first floor. This type of extension can be built to the rear or side of your property, depending on the available space and your specific needs.

Unlike a single storey extension, a two storey extension allows you to create a much larger and more versatile living area. You could, for example, extend your kitchen and living room on the ground floor while adding one or two new bedrooms and a bathroom on the first floor. This makes it an incredibly efficient way to gain a substantial amount of extra room.

Advantages of a Double Storey Extension

Choosing a double storey extension comes with a wealth of benefits for you and your family:

Maximise Your Space

The most obvious advantage is the significant increase in living space. A two storey extension can provide the extra bedrooms, bathrooms, or living areas that your family needs to live comfortably.

A Cost-Effective Solution

While the initial outlay is higher than for a single storey extension, a double storey extension is more cost-effective per square metre. You’re essentially getting twice the space for not much more than the cost of the foundations and roof.

Increase Your Property’s Value

A well-designed and constructed double storey extension is a sound investment that can add significant value to your property, often far exceeding the initial cost.

Avoid the Stress of Moving

Moving house is consistently ranked as one of the most stressful life events. An extension allows you to stay in the home and neighbourhood you love while still gaining the additional space you need.

Versatile Design Options

From creating a large, open-plan kitchen-diner to adding a master bedroom with an en-suite, the design possibilities are endless. A double storey extension gives you the flexibility to create a home that truly works for you.

What is the Cost of a Double Storey Extension?

The cost of a double storey extension in the UK can vary significantly depending on a number of factors, including the size of the extension, the complexity of the design, the materials used, and your location.

As a rough guide, you can expect to pay between £1,800 and £2,500 per square metre for a double storey extension. For a typical 40m² two storey extension, this would equate to a total cost of between £72,000 and £100,000.

It’s important to remember that this is a general estimate, and the final cost will depend on your specific project. At Abbey Partnership, we provide a detailed and transparent quoting process, so you’ll know exactly what to expect before any work begins.

Double Storey Extensions: Permitted Development and Planning Permission

Navigating the world of planning permission can seem complex, but it doesn’t have to be. Here’s a breakdown of everything you need to know:

Permitted Development Rights

In some cases, you may be able to build a double storey extension without the need for a full planning application under what are known as ‘Permitted Development’ rights. For a two storey extension to fall under Permitted Development, it must meet a strict set of criteria, including:

• It must not extend beyond the rear wall of the original house by more than 3 metres.
• It must be at least 7 metres from the rear boundary.
• The eaves and ridge height of the extension cannot be higher than the existing house.
• The materials used must be similar in appearance to the existing house.
• No balconies or verandas are allowed.

When Planning Permission is Required

If your proposed extension does not meet the criteria for Permitted Development, you will need to apply for planning permission from your local authority. This is typically the case for larger extensions, or for properties in conservation areas or other designated areas.

The planning permission process can take around 8-12 weeks, and it’s advisable to have an architect or a design and build company like Abbey Partnership to help you with your application.

Why Choose Abbey Partnership for Your Double Storey Extension?

Choosing the right company to build your double storey extension is the most important decision you’ll make. At Abbey Partnership, we have years of experience in designing and building high-quality home extensions across the UK.

Here’s what sets us apart:

• A Complete Service: We offer a complete design and build service, from initial concept to final completion. We’ll handle everything, including architectural drawings, planning applications, and construction, making the whole process as smooth and stress-free as possible for you.
• Expert Craftsmanship: Our team of skilled and experienced tradespeople are dedicated to delivering the highest standards of workmanship. We use only the best materials to ensure a finish that is not only beautiful, but also built to last.
• Transparent Pricing: We believe in honest and transparent pricing. We’ll provide you with a detailed quote upfront, with no hidden costs or surprises along the way.
• Excellent Communication: We’ll keep you informed at every stage of the project, with regular updates and a dedicated project manager to answer any questions you may have.

Realise Your Home’s Full Potential

A double storey extension is more than just an extra room; it’s an opportunity to create a home that is perfectly tailored to your lifestyle. Whether you’re dreaming of a larger kitchen, an extra bedroom, or a dedicated workspace, contact Abbey Partnership today to turn your vision into a reality.

Double Storey Extensions: FAQs

Can I build a 2 storey extension without planning permission?

In some cases, yes. If your proposed extension meets the strict criteria for Permitted Development rights, you may not need a full planning application. However, it’s always best to check with your local authority or a planning expert.

How big can a double storey extension be?

Under Permitted Development, a two storey extension cannot extend more than 3 metres from the rear of the original house and must be at least 7 metres from the rear boundary. If you want to build a larger extension, you will need to apply for planning permission.

Is it worth doing a double storey extension?

A double storey extension is a significant investment, but it can add substantial value to your property and provide you with much-needed living space. For many families, it’s a more cost-effective and less stressful alternative to moving house.

How long does a 2 story extension take to build?

The construction phase of a typical double storey extension can take between 3 and 6 months. However, the overall project timeline, including design and planning, can be closer to a year.

Do I need an architect for a double storey extension?

While it’s not a legal requirement, it’s highly recommended to use an architect or a design and build company like Abbey Partnership. They will ensure your extension is well-designed, structurally sound, and complies with all building regulations.

Can I live in my house during the construction?

In most cases, yes. However, there will be some disruption, particularly during the initial groundworks and when the extension is being connected to the existing house. We’ll work with you to minimise the impact on your daily life as much as possible.

Will a double storey extension add value to my home?

A well-designed and constructed double storey extension can add significant value to your property, often providing a substantial return on your investment.

What’s the difference between a side and rear extension?

A rear extension is built onto the back of your property, while a side extension is built onto the side. The best option for you will depend on the layout of your property and the available space.

Do I need my neighbour’s permission for a double storey extension?

You don’t need your neighbour’s permission to build an extension, but you will need to inform them of your plans under the Party Wall Act if you share a boundary wall. It’s always a good idea to speak to your neighbours about your plans at an early stage to avoid any potential issues.

What are the main stages of building a double storey extension?

The main stages of building a double storey extension include:

1. Design and Planning: Creating the architectural drawings and obtaining any necessary planning permission.
2. Groundworks: Preparing the site and laying the foundations.
3. Superstructure: Building the walls and roof of the extension.
4. Weatherproofing: Installing the windows, doors, and roof covering.
5. First Fix: Installing the plumbing, electrics, and internal stud walls.
6. Plastering and Second Fix: Plastering the walls and ceilings, and fitting the internal doors, skirting boards, and architraves.
7. Finishing: Decorating, flooring, and installing the kitchen and bathrooms.

What are some popular double storey extension ideas?

There are many fantastic double storey extension ideas you could consider. Popular configurations include creating a large, open-plan kitchen-diner on the ground floor with bi-fold doors leading to the garden, while adding a master bedroom with an en-suite and a walk-in wardrobe on the first floor. Other ideas include adding a playroom or home office downstairs with extra children’s bedrooms and a family bathroom upstairs.