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side return extension into garden for city home


SL800 slimline aluminium sliding doors, fixed windows and rooflights for extension in London


Side return extension for South London home


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Our glass extensions are custom-made to your architect’s specifications and dimensions. With slimline frames made from robust aluminium and steel, and finishes to complement your home’s architectural style, our range offers exceptional choice and quality for your project.

Garden extension with 3 sets of sliding doors

modular glass extensions

ODC offers modular glass extension designs. Structural glass walls, glass roof panels or rooflights are combined with floor to ceiling glass sliding doors or bifolds to create bright, light new spaces with instant access to the outdoors.

Side infill extensions or side return extensions, as they are also called, are a popular option with homeowners, making great use of a passageway or storage area to extend a kitchen or open up family spaces.

From double storey designs with up and over glazing to a three-sided glass box with a solid roof – our extensive range of products have the technical specifications to deliver the look and functionality you want.

ODC team at work on sliding door design specifications

Tell us about your design

Our teams have a wealth of project experience and the technical expertise to create unique glass extensions for a wide variety of homes.

Wondering if bifolds or sliding doors will best suit your new space? Want to explore how a large picture window will look? Interested to learn more about advanced security features or solar control glass?

Whether you’re looking for a simple lean-to glass box or a full width house extension, they’ll have the answers for you and your architect – and lots of options.

Customised black glazing bars door for a period home

Colours and finishes

With an extensive range of finishes and colours, a custom-designed ODC extension will transform the look of your home.

Explore the idea of floor to ceiling glass held in black frames and heritage or crittall style doors to complement the character of a period home.

Or choose frames in a particular colour to ensure your new extension harmonises with existing facades, doors and windows

Individuality and aesthetic are core to our designs.

Glass extension with light interior

thermal efficiency

Our double-glazed products are designed to meet the highest thermal efficiency standards. They form insulated, comfortable spaces that easily meet the latest building regulations.

Delight in a design that will maximise light and bring a feeling of wellbeing, whatever the weather.

ODC Sliding Doors and Bifolds for Glass Extensions

High performance slimline sliding doors with superb energy efficiency

Premium sliding doors with great looks, performance and enhanced security

Bifolds for the widest openings to the outside

ODC Glass roof and walls for extension

GLASS ROOFS and GLASS Curtain WALLS explained

Our modular fixed glass units can form minimalist glass façades and glass roofs to suit any extension design.

Large areas of glass can be created with custom-made panels or by connecting multiple panels using structural silicone. Depending on its dimensions, glass beams or steel sections will give your glass walls and roof the structural support they require.

Double height and single storey extensions featuring beautiful expanses of clear glass and incorporating any of ODC’s extensive range of bifold and sliding doors are possible.

An extension with a ‘Grand Design’ wow factor is an option for any home. Visit this ODC project, a double storey glass extension, featuring a glass roof and a pair of custom-made front doors.

Find out more about the possibilities of Glass Curtain Walling for your project.

glass roof


  • For roofs with 5° to 45° degree pitch
  • Can be combined with vertical glass for ‘up and over’ or horizon roofs
  • Bespoke design to fit your project
  • Compatible with box gutters
  • Perfect for side infill & narrow extensions


From bespoke design right through to exacting installation, ODC offer an end-to-end service. Our expert team are here to discuss your vision with you, your architect and main contractor. You are in safe hands.

Extensions for terraced homes: explore more ideas for expanding your living space

Wintergarden Akzent Plus

Glass Conservatories

For homeowners in search of a contemporary glass conservatory to make more use of a patio area throughout the year, our Wintergardens are a great option to consider. With an extensive range of designs and colours, we can create the perfect patio glass box to complement your home’s architectural style.

Add sliding glass doors or a bifolding door system for a generous opening to the outside. Optional features include remote-controlled high-quality awnings for sun protection, built-in LED spotlights for summer evenings and cosy infra-red radiant heaters for chilly days.

Glass Conservatory Range

Patio view of bifold sliding doors on glass extension


glass conservatory




Projects by ODC

A spectacular extension for a Hampstead home

Custom heritage glazing for London extension

Life transformed by large garden extension


To help us with your enquiry, whether you’re looking to visit one of our showrooms, more information about our glazing solutions or you have a question about our products, please supply the information below or to request a quote please click here.

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Our showrooms in Chiswick and Poole have the complete range of ODC glazing products on display.

Customer Support

03300 586 793

97 Bollo Lane, London W3 8BN

Sterte Road, Poole BH15 2AF

Opening hours
Monday – 9am to 5pm
Tuesday – 9am to 5pm
Wednesday – 9am to 5pm
Thursday – 9am to 5pm
Friday – 9am to 4.30pm
Saturday – 10am to 3pm