GDO Pro 20 Insulated Side Hinged Doors
20mm Insulated Double Skin Side Hinged Doorsets
Greater performance, strength, and security for the price of many single skin uninsulated hinged garage doors!
🇬🇧 Proudly Manufactured in the UK | Made to Measure | Factory Built and Assembled Ready To Fit
🔥 SPECIAL OFFER: Includes a FREE 3 Point Security Hook Locking Upgrade (worth £250) on doors over 1600mm high!
If you use your garage for an extra room, workshop, office, gym, or simply want to protect a prestige vehicle, you need more than a basic pressed steel door. The GDO 20mm Insulated Side Hinged Garage Door represents a massive upgrade in quality over tired up and over doors. Save on energy costs, vastly increase your home security, and enjoy far superior weather protection by upgrading to a double-skinned steel doorset.
Why Upgrade to Double Skinned Steel?
Unlike traditional single skin steel doors that offer poor insulation and rattle in the wind, our GDO doors are manufactured using twin galvanised steel skins bonded to a dense thermal core. This robust composite construction forms a solid 20mm deep insulated leaf that provides substantially more rigidity and stability. The thicker panels allow for heavier-duty hardware, meaning these doors lend themselves to much stronger multi-point locking systems and adjustable hinges, giving you the kind of reassuring, high security clunk usually reserved for an expensive front door.
Engineered for maximum thermal performance, these doors boast a superb U-Value of 2.8W/m²k. By keeping the cold out and retaining internal warmth, they help regulate the temperature and humidity of your garage, saving you money on electric heating in workshops or utility rooms. Furthermore, both door panels sit perfectly inside a heavy-duty, factory-fitted box section steel sub-frame. Combined with double weather seals around the door leaf and a built-in threshold strip, they create an impeccable barrier against draughts, dust, and rain.

The Difference is Clear
Standard Single skin,
non-insulated door
GDO 20mm Double-Skinned
Insulated door
Reasons to Choose GDO Pro 20 Insulated Doorsets
- Made to Measure as standard at no extra cost, ensuring a snug fit into your structural opening with no need for unsightly infills or packers.
- Pre-fitted handles, hinges, fittings and hardware on all doors. The factory assembled steel sub-frame guarantees the easiest possible on site installation.
- Concealed Shoot Bolts at the top and bottom of the inactive door leaf, holding the secondary door panel securely in place against attempted break-ins.
- Manufactured in the UK supporting high grade local engineering and ensuring consistently high structural integrity.
- Durable Powdercoat Finish available in 27 different attractive colour options to perfectly match your home.
- High-Security Hinges are colour matched as standard and are fully adjustable in 3 directions for maximum flexibility in leaf alignment (2 hinges standard, 3 on larger leaves).
- Left or Right Hand Door Opening available to select at no extra charge. Doors are split 50/50 opening as standard and can be configured to open outwards or inwards.
- Exceptional Weathersealing with a built-in box profile threshold included as standard (please note: level ground is essential for maximum effectiveness). The design also features double perimeter seals to limit dust and draughts from entering the garage.
- Single-point mortice locking and latch included as standard, featuring a lever handle, deadlock, adjustable keep, and high-security anti-snap euro profile cylinders. It includes an internal thumb turn for effortless and safe operation from inside.
- FREE 3-Point Hook Locking Upgrade (worth £250) currently included on all doors over 1600mm high, offering unmatched peace of mind and heavy-duty defence against forced entry.

Standard Designs
Choose from a Solid Panel, Wide Ribbed, or Medium Ribbed design.
Classic Traditional Design with Glazed Windows
The Perfect Timber Replica
This elegant windowed design is a perfect visual replica of the traditional timber side-hinged garage doors seen on so many period and character homes around the UK. It combines the classic, sought after aesthetic of vertical boarding and top light glazing with all the modern benefits of 20mm double-skinned steel. Enjoy natural light in your garage alongside unbeatable security, zero rot, no repainting, and vastly superior insulation.
Modern Glazed Designs
Choose from ...
Choose from our On Trend Range of Colours
All doors are factory finished in a highly durable powder coat.
Window GreyRAL7040
Traffic WhiteRAL9016
Light GreyRAL7035
Pebble GreyRAL7032
Dusty GreyRAL7037
Traffic GreyRAL7042
Light GreyRAL7035
Silver GreyRAL7001
Iron GreyRAL7011
Slate GreyRAL7015
Graphite GreyRAL7024
Anthracite GreyRAL7016
Black GreyRAL7021
Jet BlackRAL9005
Cobalt BlueRAL5013
Gentian BlueRAL5010
Signal BlueRAL5005
Sky BlueRAL5015
Moss GreenRAL6005
Fir GreenRAL6009
Chartwell Green
Ruby RedRAL3003
Traffic RedRAL3020
Chocolate BrownRAL8017
Clay BrownRAL8003
Mahogany BrownRAL8016
Light IvoryRAL1015
CreamRAL9001
Traffic YellowRAL1023
Moss GreenRAL6005
Chartwell GreenWhy Choose Insulated Side Hinged Garage Doors for Your Home?
As modern living evolves, the garage is rarely used solely for parking a car. Whether you are transforming your space into a home gym, workshop, office, or simply need a secure utility area, GDO Pro 20 insulated side-hinged doors offer the ultimate blend of robust security, convenience, and thermal performance.
Maximise Your Usable Space
Traditional single-skin up-and-over doors offer virtually no climate control, leaving garages freezing in the winter and damp during heavy rain. The 20mm dense thermal core in our GDO doors acts as a heavy-duty barrier against the elements. By retaining internal warmth and blocking cold draughts via the built-in threshold and perimeter seals, you can effectively regulate the temperature of your garage. This protects high-value items, tools, and classic vehicles from damp and condensation while saving you money on electric heating bills.
Effortless Pedestrian Access
Side hinged garage doors are the pinnacle of everyday convenience. Split 50/50 as standard, they allow you to pop in and out of the garage on foot without having to reveal the entire contents of your garage to the street. Whether you're grabbing a bicycle, a lawnmower, or gym equipment, you only need to open the active leaf, drastically reducing the amount of cold air that escapes during the winter months.
Uncompromising Security for High-Value Storage
Security is paramount when storing expensive equipment. Because double-skinned panels are significantly thicker and stronger than pressed steel, they can support heavy-duty, premium locking hardware. Combined with the free 3-point hook locking upgrade (available on doors over 1600mm high), anti-snap euro profile cylinders, and concealed shoot bolts, the GDO Pro 20 doorset provides a reassuringly high level of defence against forced entry, ensuring you have absolute peace of mind.














