Anthracite Grey Vermont Shade

Thermal Performance

Learn more about how Rockdoor built a composite door that wasn’t only built for strength, but also designed to keep the warmth in and the cold out.

Why choose a thermally efficient composite door?

When choosing white goods such as washing machines, fridge-freezers and tumble dryers, one of the first things we look at is the energy rating certificate of the product before purchasing.

This purchase decision is now becoming increasingly important when choosing energy efficient front doors and back doors, due to the levels of heat that can escape from your home, unless you choose doors made from thermally efficient materials.

Rockdoor composite doors use various thermally efficient materials during their construction to reduce heat loss, whilst also benefitting from features like S-Glaze technology which eliminates draughts through the glazing aperture of the door.


View the Rockdoor range of composite doors

The Rockdoor range of composite doors comes in 25 composite door styles, all available with 13 different door colours to choose from. So no matter if you’re looking for new front doorsback doors or even French doors or a stable doors, there’s a wide range of Rockdoor composite doors available to compliment the look and style of your home.


What makes a Rockdoor thermally efficient?

Thermally efficient PVC-U skins, a 50mm thick sash, an lon gasket, an aluminium reinforced inner frame encapsulated in PVC-U and high-density polyurethane foam work together to enable Rockdoor to achieve industry leading thermal performance ratings.

It’s not just about the materials we use though, it’s how we use them.

An example of this is our very own S-Glaze technology. Whilst it was designed to keep homeowners secure, it has also provided a huge advantage over our competitors when it comes to thermal performance.

Why is S-Glaze so effective against drafts?

The reason S-Glaze is so effective, is because it locks the glass into the door for life, meaning no draughts can get through the glazing aperture. To put it simply – there is nowhere for the air to go, therefore it cannot escape.

Clear Backing Glass is another great way to improve the thermal performance of your Rockdoor. A special coating can be applied to clear glass, making it even more thermally efficient. This cannot be applied to textured glass designs, so if you’re really looking to lower your energy bills – choose clear glass!

A low PVC-U Threshold is another option that you can choose to help reduce energy bills and achieve that all-important A energy rating!

Find a local Rockdoor installer today and find out more about making your new Rockdoor as thermally efficient as possible.

Reasons to Choose a Rockdoor

Core Benefits

Rockdoors inner strength is unsurpassed thanks to a combination of a 360° aluminium reinforced inner frame and high-density thermally efficient PU foam. Customers can also choose steel mesh reinforcing for the ultimate in security.

£1,000 Guarantee

Our lock cylinders are burglar proof. A TSOO7 3 star rating, SS 312 Sold Secure Diamond Standard and Secured by Design accreditation see to that, plus our £1,000 security guarantee. Customers also receive three Rockdoor branded keys as standard.

Forced Entry

Rockdoors are designed for strength, it is in our DNA. For over 25 years, we have led the way in composite door development to ensure our doors protect homes and families from unwanted intruders and forced entry.

Hook up with Rockdoor

Strong sintered steel multi point hook locks with a 25mm throw, securely attach the door to the frame to ensure it cannot be forcibly opened by burglars whilst ensuring a better sound and weatherproof seal.

Glass Leading Security

Rockdoors feature S Glaze technology, meaning your glass is locked into your door for life, for added security. It also means no glazing cassettes are used which are prone to fading and discolouration.

Stronger, it's Official!

Rockdoor is consistently found to be one of the most secure doors available in the UK, studies show that a Rockdoor is 35% stronger than a typical GRP door.

Create your own Rockdoor now and get it expertly fitted

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