ARE COMPOSITE DOORS ENERGY EFFICIENT?

ARE COMPOSITE DOORS ENERGY EFFICIENT?

ARE COMPOSITE DOORS ENERGY EFFICIENT?

The UK home improvement market has seen a significant shift in recent years toward energy efficiency, driven primarily by rising energy costs, but also by growing awareness of environmental concerns, and government regulations aimed at reducing carbon emissions. 

And when it comes to improving the energy efficiency of their property, one of the most popular choices for homeowners looking to reduce energy bills – aside from replacing all the windows – is by upgrading front door insulation with a composite entrance door.

With a combination of durability, security, style and relatively low cost, it has become a staple in modern home improvement.

But for homeowners that are considering investing in a more energy efficient front door, are composites really the best option? How do they compare, for example, to doors constructed from timber, aluminium or steel – and do they have any other disadvantages?

This blog explores the energy efficiency of composite entrance doors, their strengths and weaknesses and asks the question – is there a better solution?  

What are composite doors?

Before delving into their energy efficiency, it’s essential to understand what composite doors are and how they are constructed. Composite doors are typically made from a combination of materials that are engineered to offer optimum strength, energy efficiency and aesthetics:

• GRP (Glass Reinforced Plastic) Skin: This provides the door with a tough, weather-resistant exterior.

• Insulating Core: Often made from polyurethane foam or timber, the core is designed to provide thermal insulation and reduce heat transfer.

• Steel or Aluminium Reinforcement: This gives the door structural strength and enhances security.

• Wooden Frame: While wood is used sparingly, it contributes to the door’s rigidity and overall aesthetics.

This multi-material construction is designed to maximise the benefits of each component while minimising their drawbacks, resulting in a door that can be sold as durable, secure, good looking and weather-resistant.

It’s also important to understand how composite doors – and all entrance doors – are measured for their energy efficiency.

This is done either with a DSER value, which rates energy performance from E to A++, in much the same way that you would see energy ratings for household electrical appliances such as fridges and washing machines, and also with U values.

For reference, current building regulations state that all exterior doors at a property need a minimum U value of 1.6 W/m2k (Scotland) and 1.4 W/m2k (England & Wales). The lower the U value, the more energy efficient the door is, and it is possible to find products on the market that offer U values of around 0.8 W/m2k, which is roughly equivalent to a Passivhaus standard for energy efficiency.

So far, so good – but are there any downsides?

What are the disadvantages of a composite door?

While they are engineered to be as strong and energy efficient as possible, the fact they are made from a combination of different materials is actually the biggest weak point of composite doors.

When subjected to direct sunlight, cold conditions or the ingress of water moisture, those materials contract and expand at different rates, resulting in a door that can twist and warp over time.

This means that it will no longer fit properly, and in extreme cases, it becomes impossible to operate or make it secure because the locking mechanisms and hardware are no longer aligned.

It’s a potential nightmare for homeowners and a constant bugbear for installation companies that have to deal with upset customers.

What other types of entrance doors are there?

Composites are not the only type of entrance door on the market. Homeowners can also choose from uPVC panel doors, which are more affordable but far less secure or thermally efficient, or solid timber doors that offer a premium finish (and price tag) but are also ‘colder’ and can require frequent maintenance.

High performance, ultra-stylish aluminium entrance doors are also an option, but historically, these have had limited appeal due to their top end price tag.

Gerda – the ultimate entrance door

Gerda Doors are unique in that they offer outstanding energy efficiency but with an incredibly robust aluminium and steel construction that is guaranteed to never twist or warp, no matter what conditions are thrown at them.

And unlike the majority of premium aluminium entrance doors on the market, they are also available at a price point very similar to a composite door, but in a product that is streets ahead in terms of quality, energy efficiency, security and aesthetics.

Who are Gerda?

Gerda is a brand that was founded in Poland in 1987 and has since established itself as a true market leader in entrance door design, offering a comprehensive range of solutions in the UK via Pioneer Trading, a highly respected window and door manufacturer, based in Essex.

There are four ranges to choose from, the OPTIMA Series, THERMO PREMIUM Series, THERMO PRIME Series and the Altus Series, all which offer a wide variety of styles and finishes, and with energy efficiency performance from as low as 0.74 W/m2K – making it one of the most thermally efficient entrance doors of any type available on the market.

And because Gerda doors are so well engineered and strong they are also incredibly secure, offering the RC3 standard for anti-burglary.

Are composite doors energy efficient?

There is no doubt that composites offer an effective solution to homeowners who are looking to lower energy bills, especially if they are replacing an older entrance door, but as we have explored in this blog, that is frequently offset by the issue of warping and bowing.

However, what we have also highlighted is that, thanks to Gerda, it’s now possible to invest in a front door that offers even better energy efficiency and aesthetics – and at a similar price point – but without the risk of it twisting out of shape and becoming unusable when it gets too hot or cold.  

Ends.

All enquiries to: Tina Beal, Gerda Doors at Pioneer, 01245 362236 –www.gerdadoors.co.uk

Editors’ notes:

Pioneer Trading Company Essex Ltd operates from manufacturing and distribution sites in Chelmsford, Essex. The company has an exclusive partnership with Gerda for the distribution of residential doors and other products, in the UK and Ireland.

Gerda Doors has operated since 1987 and is a leader in the supply of doors, locks, and door hardware, based upon innovative safety and security technologies.

© 2025 Pioneer Trading Company Essex Ltd.

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