What Is a Composite Door Made Of? (And Why It Matters for Your Home in Dundee)
- admin256681
- Apr 11
- 5 min read
When it’s time to replace your front or back door, the term “composite door” comes up a lot. But what exactly is a composite door made of—and why does it matter when choosing one for your home?
At Doorquay, we fit composite doors across Dundee, Fife, Perth, and Arbroath, helping homeowners find the perfect balance of security, insulation, durability, and kerb appeal.
In this guide, we’ll break down what’s inside a composite door, how different brands are built, and how to choose the right one for your home.
What Is a Composite Door?
A composite door is an external door made using a combination of materials—each chosen for a specific strength. By layering materials like timber, uPVC, insulating foam, aluminium, and glass-reinforced plastic (GRP), these doors offer superior performance compared to single-material doors like timber or uPVC alone.
Composite doors are:
Stronger than traditional doors
More energy-efficient (great for Scottish weather)
Low-maintenance
Highly secure, with multi-point locking
Available in a wide range of styles and colours
Whether you’re looking for a front door in Dundee, back door, or even composite French doors, they’re a smart, long-term upgrade for any home.
What’s Inside a Composite Door?
While all composite doors share a layered construction, not all are built the same. Different brands use different core materials, reinforcements, and glazing technologies—so understanding what’s inside helps you make a more informed decision.
Types of Composite Door Cores
Solid Timber Core (e.g. Solidor)
Solidor doors use a 48mm laminated timber core—heavier and denser than most. This solid core gives the door a premium feel, excellent durability, and impressive security.
Best for:
Homeowners who want a heavier, more traditional feel
Those looking for premium finishes and solid performance
2. PU Foam Core (e.g. Hurst)
Hurst composite doors use a high-density polyurethane foam core, which is lightweight, energy-efficient, and great for everyday use. The foam core expands to fill the internal space of the door, making it a cost-effective and thermally efficient choice.
Best for:
Busy households looking for low-maintenance performance
Great insulation with an affordable price point
3. High-Security Reinforced Core (e.g. Rockdoor)
Rockdoor composite doors are designed for security and strength from the inside out. At their core is a high-density PU foam, surrounded by a fully aluminium-reinforced 360° inner frame—making the structure exceptionally strong and stable.
Customers can also choose steel mesh reinforcing for an added layer of protection. Combined with S-Glaze technology (where the glass is part of the structure, not just inserted later), and TS007 3-star locks as standard, Rockdoor offers high performance home security across the board.
Best for:
Security-conscious homeowners
Anyone looking for long-lasting strength without compromising on design
Composite French doors and back doors with built-in reinforcement
What About FD30 Composite Fire Doors?
If you live in a flat, HMO, or a building with a shared entrance, Scottish building regulations require your external door to be an FD30-rated fire door—meaning it must resist fire and smoke for at least 30 minutes.
At Doorquay, our FD30 composite fire doors in Dundee are:
Made with solid fire-resistant cores
Fitted with intumescent strips that expand in heat
Fully compliant with Scottish fire regulations
Still available in a range of styles and finishes
They’re a safe, stylish, and compliant solution for properties that need fire-rated access without compromising on looks.
Can Composite Doors Be Used for Any Entry Point?
Yes—composite doors are extremely versatile. We regularly install them across Dundee and nearby areas as:
Front doors – where security, kerb appeal, and insulation matter most
Back doors – for durability, weather resistance, and peace of mind
French doors – like the reinforced Rockdoor French Door range
Whatever style you choose, composite doors give you long-term performance, design flexibility, and built-in security features—all fully fitted with care by Doorquay.
Why the Materials Inside Matter
Here’s why choosing the right composite door build matters:
Security: Solid cores, aluminium reinforcement, and steel mesh all affect how your door stands up to forced entry.
Energy Efficiency: The type of insulation inside the door (foam or timber) plays a big part in how well it retains heat.
Durability: The outer layer (usually GRP) protects your door from warping, cracking, and fading—even in Scotland’s unpredictable weather.
Lifespan: A well-built composite door should last 20–30 years or more, especially when properly installed.
Choose with Confidence
At Doorquay, we help you find the right composite door based on your home, your style, and your priorities. Whether you’re focused on security, insulation, or a bold new look for your home—we’ll guide you with honest advice and local knowledge.
All our composite doors come with:
A 10-year guarantee
Expert installation by trusted fitters
Recycling of your old door
And support at every step
FAQs About Composite Doors
What materials are used to make a composite door?
Composite doors are made from a combination of materials like timber, uPVC, high-density insulating foam, aluminium reinforcements, and GRP (glass-reinforced plastic). Each layer is chosen to enhance security, energy efficiency, durability, and design. Different brands—like Rockdoor, Solidor, and Hurst—use slightly different core constructions to offer varied performance and finishes.
Are solid core composite doors better than foam-filled ones?
What’s the most secure composite door?
Can composite doors be fire-rated?
Are composite doors suitable for back doors or French doors?
How long do composite doors last?
Do composite doors need much maintenance?
Ready to choose your new composite door?
Start with a free quote, or download a brochure. During our design visit we’ll bring samples and help you find the right fit for your home.
