Blog>Ideas>Double storey extension ideas: Level up your home
Last updated: 22 February 2024
Double storey extension ideas: Level up your home
Looking for double storey extension ideas? Whether you're after open-plan living, a new bathroom and kitchen, or home office and master suite, your opportunities just doubled. So, keep scrolling for all the innovative and practical ways you can level up your home.
Our double-storey extension ideas are all about maximising your square footage. Transform your home by opening it up, reimagining the layout, and adding a bedroom or two for increased value (up to 20%!).
A double-storey extension elevates your home - both literally and figuratively. That's why we're going to take a look at all the ways you can reinvent your abode with double the style, double the aesthetics, and double the appeal.
Can't wait to get started? Pop your postcode into the search bar below to browse a selection of our top extension experts - each ready to help level up your home.
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Double-storey extension ideas for maximum appeal
Two-storey extension ideas with open-plan layouts
The best thing about a two-storey extension is all the extra space you get to enjoy. So, why not open it up even further with a mezzanine floor that overlooks your kitchen and lounge area?
This charming design embraces open-plan living for a sociable and fun environment. With interesting features and plenty of bright decor, it's a natural retreat that's perfect for entertaining.
Related content: Open plan living cost.
Unique 2-storey house extension ideas
This porch and dormer double extension boasts a unique design befitting those who like to do things differently. The dormer is supported by pillars that frame the porch while the exterior is finished with peach cladding, brown framed windows, and matching fencing.
What makes this home particularly unique is the mansard-style roof, which is finished with high-performance metal tiling for an idyllic and welcoming picture.
We permit the development of this two-storey extension idea
For those who want a double-storey extension under permitted development (who likes paperwork?!), then consider an open-plan mezzanine (like pictured).
It's a simple but effective design that has an upstairs office on the mezzanine floor and a tasteful breakout and storage area on the bottom. As a result, it maximises space without costing the earth.
Two-storey side extension ideas on a detached house
If you're blessed with a detached house and have the square footage to pull it off, consider a double-storey side extension. This homeowner opted for a garage and upper dormer conversion for an economical use of space.
Not only does this increase the value of the property, but it adds character and style. Without the double-storey extension, this home is a simple bungalow on a large plot of land.
Related content: Side return extension cost guide.
Two-storey rear extension ideas for terraced house
Open up your terraced house with a space-enhancing two-storey extension design. The bi-fold doors invite plenty of light to flood in from the garden, complementing the neutral tones of the contemporary kitchen.
This leaves the upper storey free to become something new, such as a second bedroom, small bathroom, office, or reading nook.
Go green with an eco-friendly roof design
Do your part for the planet by installing a green roof on your property. Not only do you promote sustainability, but you're enhancing the visual appeal of your home with nature-loving decor.
Green roofs have lots of environmental benefits when installed using low-maintenance native plants. Read our guide to green roofs and our green roof cost guide for more interesting information.
Related content: Eco house design: how to create your green home.
Ideas for open-plan living in a double-storey extension
With shrinking square footage a blight on the property market, making the most of your precious space is imperative. That's why open-plan living is always on-trend.
So, when it comes to double-storey extensions, why not blend two rooms into one? It's an easy way to give the illusion of a much larger home. Whether that's your kitchen and lounge, your lounge and conservatory, or your kitchen and utility, inject cohesion throughout with a seamless design scheme.
Consider an extra bathroom in a double-storey extension
The upper storey of a double extension doesn't enjoy the same attention as the lower decks. However, that doesn't mean it's not equally as important.
Most homeowners opt to turn the top storey section into a bedroom or bathroom – and for good reason! Both of these rooms add value to a home, making it an attractive prospect when it's time to sell. However, for busy households, an extra bathroom or wetroom is never unappreciated.
Add a small double-storey extension for maximum indoor and outdoor space
Although we tend to think double-storey extensions are large and foreboding, they don't have to be. A simple and small design adds enough of an impact to make it worth the trouble.
This compact design (pictured) blends with the original home beautifully. With a popular glass bi-fold design and skylight, all the attention is on the ground floor. The upper storey is barely noticeable due to the matching exterior paint.
Add an office to your two-storey extension design
Another design that would pass under permitted development, this double-storey extension opens up the dining room and leads onto a carpeting office area.
Beneath this mezzanine is a utility room and atrium full of plants, which thrive due to the slanted skylights that let in the perfect amount of sunlight.
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FAQs
Do you need planning permission for a 2-storey extension?
Permitted development has strict rules when it comes to two-storey extensions. For example, you can't extend beyond your home's rear wall by over three metres, and your extension also can't come within 7 metres of your property's rear boundary wall (i.e. where your land ends).
You also can't have a balcony or veranda. So, those with small gardens won't benefit. Consequently, getting planning permission is often the best course of action.
How close can a two-storey extension be to the boundary?
First off, it's helpful to define what a boundary means when it comes to extensions. In this case, it's the invisible lines that divide one person's land from their neighbours'. Fences or walls often mark the boundaries to help define them.
Your local authority will have its own rules and building regulations that you should check before applying for planning permission. However, if your double-storey extension design falls within permitted development, you can skip the checks and just make sure you leave a minimum of 7 metres between the rear boundary line (e.g., the end of your garden) and the rearmost part of your extension. (In Scotland, the limit is 10m, and in Wales, it's 10.5m).
How long does a 2-storey extension take to build?
On average, expect your double-storey extension to take between 8 – 14 weeks to complete. This is if everything runs on time, nothing goes wrong, and the UK weather is kind to you! Our extension planning guide breaks down exactly what to consider when working out how long your project will take.
How much would a 2-storey extension cost?
The average price of a double-storey extension is £1,900 per sqm. This includes framing, roofing, and foundations. Of course, the final price will depend on several factors such as the quality of the build, the materials used, and your location.
You should also factor in other costs such as extension planning drawings, architect fees, surveyors, party wall agreements, and internal fittings and fixtures.
Read our guide: How much does it cost to build a double-storey extension? for more comprehensive information.
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