What is a CosyRoom?
CosyRoom is an extension, orangery or conservatory built with a brand new construction method, using an insulated walling system instead of brick. These walls consist of interlocking lightweight, thermally efficient insulated panels. Because of their lightweight design, they can utilise existing conservatory bases, eliminating the costly process of replacing an old base. Building regulation compliant, you can customise the roof type, windows, doors and wall finishes to create the extension of your dreams.
Reasons to Choose CosyRoom
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Faster & Easier to Install
CosyRoom modular extensions can be installed up to five times faster than a traditional conservatory or extension. The interlocking walls are manufactured to size off-site, and can be installed in any weather, meaning fewer installation days and less disruption for your home.
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Energy Efficient
CosyRoom walls are up to five times more energy efficient than traditional walls in UK homes. This means your prefab extension comfortable throughout the year, helping to reduce overall heating bills in the winter and keep cooler in summer.
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Space
CosyRoom walls are over 25% slimmer than brick and block walls and rooms. This gives you up to 15% more usable floor space than that of a traditional brick build. More space means you can do more with less and add more value to your home.
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Sustainable & Eco-Friendly
The CosyRoom wall system is 60% more carbon efficient than traditional brick walls. Because the walls are manufactured off-site, there is zero waste in production methods on-site, meaning less mess and debris too. CosyRoom is a much cleaner and more sustainable way to build.
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Fully Approved & Certified
CosyRoom is independently accredited by the BBA for quality, strength, stability, moisture resistance and fire resistance. It also exceeds Building Regulation thermal insulation specifications, achieving a U-Value of 0.17W/m²K.

CosyRoom Colour Options
Choose the perfect colour for the doors and windows on your new modular extension. Create the look you want with our range of uPVC finishes, including dual colour options, and a huge choice of durable powder-coated aluminium colours.
CosyRoom Window & Door Options
Choose the perfect windows and doors for your new modular extension. We also offer a wide range of roof options including glass and tile as well as orangery roof lanterns.
5 Steps to Your CosyRoom
Do I Need Planning Permission for CosyRoom?
The majority of CosyRoom installations won’t require planning permission. Because they are only one storey, and often built on existing bases, they are considered a permitted development. However, you will need planning permission in a few instances. For example, if your home is listed then you will need planning permission. For a full breakdown, head over to our helpful planning permission guide.

Hear it From CosyRoom Customers
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10-year Guarantee
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Our products are made from start to finish in a British factory by skilled craftspeople.
Price Match
If you find cheaper like for like uPVC windows elsewhere, we'll match the price.

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Decide if a CosyRoom Modular Extension is Right for Your Home
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Common Questions About CosyRoom Modular Extensions
A modular extension is any type of extension, orangery or conservatory built using non-traditional building methods. These prefabricated wall systems are manufactured off site and assembled on site in a much less time consuming way with less mess and hassle for you.
The short answer is yes, you can get a mortgage on a house with a modular extension. As with any extension however, it would need to have been created following all planning rules and building regulations. Our CosyRoom prefab extensions are fully certified and follow all building regulations. IF you do require any planning permission, then we take care of the whole process for you.
Modular extensions are a great way to add an addition to your home. They are often much faster to build than traditional extensions, they are more environmentally friendly, better insulated and overall more cost-effective than traditional extensions.
Our CosyRoom prefab extensions are certified to last a minimum of 60 years. This makes them a great long term investment for your home. We offer a 10-year guarantee on parts and labour for our CosyRoom extensions, as well as a host of other guarantees on your windows and doors.
In most cases, you probably won’t need to obtain planning permission for a prefab extension. However, that depends on a number of factors. These include its size, its position and whether your home is protected in any way. In the first instance, have a look at your local authority website to see their rules on extensions, orangeries and conservatories. When you choose an Anglian CosyRoom, we take care of any planning permission processes for you, so you don’t have to worry.

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