What are composite doors made of? (And how do they work?)

Simon Edward • 3 November 2023

Composite doors are popular for their style, strength and functionality. But what, exactly, goes into a composite door? Find out in our quick guide.


Composite doors are popular for their style, strength and functionality. But what, exactly, goes into a composite door? Find out in our quick guide.

Composite doors are a modern and popular choice for homeowners who are looking to enhance the appeal and aesthetics of their homes.


These doors make for a versatile alternative to traditional wooden or uPVC doors and offer a wide range of benefits, including better security and durability.


But what are composite doors actually made of? Is it just plastic? And what's so special about them, anyway?


What are composite doors?


Composite doors are a modern alternative to traditional doors. They come in a variety of colours and materials, which often combine to mimic the grain of a wooden door.


This type of door is very popular nowadays. There are several reasons for this – for instance, composite doors can enhance the appearance of a property, lower maintenance levels and add an extra level of security.


What are composite doors made of?


Let's nix the common myth right away: composite doors are not just made from plastic. In fact, they're composed of various different materials.


The clue's in the name. The word "composite" is defined as "made up of several parts or materials". When it comes to composite doors, that definition is right on the money.


The core of a composite door is typically made of solid timber or a solid foam-filled structure. This core is surrounded by a layer of reinforced thermosetting resins.


Finally, the outer layer is usually a high-density "skin". This mimics the appearance of wood but is much more resistant to the elements and requires minimal maintenance.


Picture of a composite door

These materials combine to create a door that's greater than the sum of its parts. For example, while the core provides strength and insulation, the resin middle layer enhances the door's robustness and weather resistance.


Different materials bring different benefits, too. For instance, you might choose a foam core if you're aiming for a lightweight result.

Composite doors are very customisable, too. Here at Calder Windows, we offer a wide variety of custom windows ranging from understated to flamboyant. This means you can give your composite door a truly personal touch.


What's the difference between uPVC and composite doors?


Composite doors and uPVC doors look similar and are both popular choices for homeowners. However, they have some very distinctive differences. 


While composite doors are made of, well, a composite of materials, uPVC doors are made entirely of unplasticised polyvinyl chloride.

We won't get into the science here. The short version is that uPVC doors are easy to maintain but are not as sturdy as composite doors. 

However, uPVC doors are more budget-friendly and affordable due to the materials used to make them. Either way, here at Calder Windows, we're happy to supply and fit whichever you choose. 


What are some of the benefits of composite doors?


There are many benefits to composite doors. In fact, you may well wonder, "Where have these doors been all my life?"

For a start, composite doors are highly durable and weatherproof – but without looking like a concrete slab on your front porch! They're specially made to endure harsh weather conditions, including rain, wind and extreme temperatures without degrading or warping.


These sturdy doors also enhance soundproofing due to the dense materials used. This also makes them more resistant to wear and tear. In the long run, they could save you money as they won't need replacing as often.


Are composite doors environmentally friendly?


We all want to help the environment in whatever way we can. But can composite doors help to shrink your carbon footprint?

From an energy-efficiency point of view, the answer is a resounding "yes!" See, composite doors are designed to trap heat in your home, which means you're less likely to keep the heating on full blast during winter.


Picture of someone looking warm and cosy in their home

Of course, this is good for your wallet – but it's good for the planet too.


Do composite doors look good?


If all these benefits aren't enough to convince you to invest in composite doors, then consider the "wow" factor.


You can choose the type of wood grain, the colour and even the windows and styles, so you'll have a door that's completely unique and stands out in the street. On older properties, they can modernise the house, and on new properties, they can add a beautiful and classic twist.


These doors are perfect for the conscientious homeowner who's looking for a high-class and reliable door to enhance the look of their home.


Are composite doors secure?


Sadly, we live in a high-crime world, so safety is a must. Can composite doors help deter those pesky burglars?


Yes. Because our composite doors are very sturdy, they make it difficult for intruders to gain entry. And even if you opt for doors with windows, they won't be flimsy single-paned glass but sturdy laminated or toughened glass.


Our composite doors also come with multi-point locking systems. Quite simply, this means the door locks at several different points once the key is turned. This makes entry even more difficult.


Where can I buy composite doors?


If you live in Yorkshire, you're in luck.


At Calder Windows, we've been supplying and fitting composite doors in Yorkshire for decades. We know the industry like nobody else – and we've built a reputation for quality workmanship, great service and very competitive pricing.

If you need composite doors fitted by a trusted and reputable supplier, don't hesitate to get in touch for a no-obligation quote.


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