Decoding Composite Doors: What Are They Made Of and Why Does It Matter?

Key Insights

• What are composite doors made of? A combination of materials meticulously chosen to maximise energy efficiency, increase strength, and deliver style.
• The core of a composite front door can be solid timber or polyurethane foam, with each offering their own benefits.
• Composite doors feature a tough outer skin made from GRP (glass-reinforced plastic), designed to provide weather resistance and durability.
• Their impressive energy efficiency benefits the homeowners through reduced energy bills and a more comfortable living environment.
• At Leamore Windows, we manufacture our own ‘Leamore composite door’ and also install leading Solidor systems.

In recent years, composite doors have positioned themselves as one of the wisest investments that an individual can make for their property.

As well as revitalising your home’s exterior, they can also reduce energy bills, increase comfort, and keep the elements out thanks to their unique multi-layered design.

This clever combination is what separates these doors from single-material options like uPVC and aluminium, with composite solutions often featuring a foam or timber core, wrapped in a tough GRP outer skin.

In this blog, we’ll explore the key layers that make up composite doors, delve into their benefits, and outline the options available to homeowners in the West Midlands, including the in-demand Leamore composite door.

The Key Layers of a Composite Door

Composite doors owe their strength and superior performance to the unique layering of materials. Here’s a breakdown of the main components and their benefits:

GRP Outer Skin

The outer layer of most composite doors is made from glass-reinforced plastic (GRP). This durable, thin layer protects the door from harsh weather conditions such as rain, wind, and UV exposure, helping to prevent it from warping, cracking, and fading.

As well as ensuring your chosen finish keeps its shine for several years, the GRP outer skin is also incredibly low maintenance and easy to clean, with a gentle scrub all it needs to look as good as new.

Its weather resistance also means the door is ideal for UK climates, offering peace of mind no matter the season.

Our Leamore composite door range, manufactured in-house, features a grained GRP outer skin that promises to look stunning for years to come.

Foam Core or Timber Core

The heart of a composite door is its core, which can be either:

• Polyurethane foam core: This is a warm thermal polyurethane foam core providing excellent insulation. It reduces heat loss and improves the door’s thermal efficiency, helping lower your energy bills. The Leamore composite door features a high insulating foam core, promising to lower heating costs.
• Solid timber core: Some composite doors, like those from Solidor (installed by Leamore Windows), feature a solid timber core, coming in at 48mm thick, wrapped in a protective layer. This gives extra strength and improves structural integrity, making the door robust and secure.

Both options offer superior insulation and security features, but timber cores provide a more traditional feel and increased durability, while foam cores often allow for lighter weight and greater energy savings.

Reinforced Inner Frame

Behind the exterior face is the inner frame, which adds strength and ensures the new door maintains its shape. This layer is often reinforced with additional materials to improve security and durability.

What Are the Main Benefits of a Composite Door?

Composite doors combine the best features of several materials, making them a popular choice for modern homeowners.

Remarkable Security

Thanks to their combination of different materials, composite doors offer much better resistance to forced entry compared to single material doors like UPVC. With a solid timber core or strong foam core, plus advanced locking systems, these doors provide a secure door you can trust.

Superior Thermal Efficiency

Composite doors are designed to keep your home warm by preventing heat loss through strong thermal properties in their cores and weather-resistant outer skins. This superior insulation translates into lower energy bills and a cosier home all year round – as well as reducing your carbon footprint.

Weather Resistance & Durability

The tough GRP skin and protective finishes mean composite doors resist warping, cracking, and fading even under the most harsh weather conditions — unlike traditional wooden options that need constant upkeep.

Low Maintenance

Unlike timber doors, composite doors require very little care – just a simple wipe with a damp cloth to keep them looking fresh, without regular painting or treatments.

Customisation Options

Composite doors come in a variety of styles, colours, and finishes. Whether you want a traditional look with a woodgrain effect or a modern door in anthracite grey, the choices are vast. You can also choose from a wide selection of door furniture like handles, knockers, and letterboxes to complete your perfect home improvement.

How Customisable Are Composite Doors?

Composite doors offer impressive customisation options to suit every home:

Colours

From classic reds and greens to sleek blacks and greys, composite doors are available in a range of colours – including over 30 premium colours and bespoke options like any RAL colour you desire, when you choose Leamore Windows.

Styles

Choose from traditional panelled designs or modern flush styles, with options for textured or frosted glazing to add privacy without sacrificing natural light.

Door Hardware

You can personalise your replacement door with a variety of hardware such as handles, knockers, letterboxes, and pull bars, available in contemporary or classic designs.

Composite Doors from Leamore Windows

At Leamore, you can choose between two excellent composite door options:

Leamore Composite Door

Leamore’s own composite door uses a polyurethane foam core and a grained GRP outer skin.

Known for its versatility, it comes in thousands of combinations of colours, glazing, and hardware.

This door provides excellent thermal performance and weather resistance, with low maintenance and customisation to suit any West Midlands home.

Solidor Composite Door

Solidor doors feature a 48mm solid timber core wrapped with two thermoplastic skins, making them exceptionally strong and secure.

Available in over 30 styles and 20 colours, Solidor offers superior security, thermal efficiency, and a wide range of glazing options.

These doors are a perfect choice if you want classic craftsmanship combined with modern technology.

Frequently Asked Questions

What is the core of a composite door made from?
It can be either a solid timber core or a polyurethane foam core, both providing excellent insulation and strength.

Are composite doors more secure than wooden doors?
Yes, composite doors offer superior strength and are fitted with advanced locking systems, providing impressive security.

How do composite doors improve energy efficiency?
Their foam core or timber core, combined with a weatherproof outer skin, reduces heat transfer, lowering energy bills as your home will lose less heat in the winter, and attract less warmth in the summer.

Do composite doors require a lot of maintenance?
No, they are low maintenance and only need occasional cleaning with a damp cloth.

Can I get a composite door in any colour?
Yes, many composite doors can be customised in a wide range of colours, including bespoke RAL colours.

Who Are Leamore Windows?

We’re Leamore Windows, a family-run home improvements company based in Walsall, proudly serving the West Midlands since 1983. Starting out as two brothers aiming to change the double-glazing industry’s reputation, we’ve grown into trusted experts in windows, doors, conservatories, and more.

We manufacture many of our own double-glazed units at our glass shop, which lets us offer bespoke designs and keep quality high. Over the years, we’ve won the ‘Windows and Conservatories Business of the Year’ award eight times, fensvoted for by local customers, which means a lot to us.

From Wombourne to Lichfield, we cover a wide area across the West Midlands, always focusing on honest service without pushy sales tactics. We’re proud to hold accreditations like FENSA, ISO 9001, and Fair Trades Registered, giving you peace of mind.

If you want to know more or see our range for yourself, you can visit us at Reaymer Close, Bloxwich, or give our office a call on 01922 473 737.

We also offer free no obligation quotes, which can be obtained on our website.