How Your Garden Room Is Built
Engineered Properly. Built to Last.
A garden room should feel like a true extension of your home — not a temporary structure at the bottom of the garden. That’s why we use proven construction methods and premium materials throughout. Every element is chosen for strength, comfort, durability and long-term performance. Here’s how we build your space from the ground up.
Ground screw base
Strong, precise, and low impact. We use specialist ground screws instead of traditional concrete foundations. These heavy-duty steel screws are driven deep into the ground to create a secure, perfectly level base. Unlike concrete, this system:
Requires minimal excavation
Causes far less disruption to your garden
Installs quickly and cleanly
Provides outstanding structural stability
It’s a modern, environmentally conscious solution that delivers long-term strength without the mess.
Structural Frame: Class 4, C24 Graded Timber
Strength at the core. The structure of your garden room is built using UC4 C24 graded structural timber — a high-strength timber that has been machine graded for load-bearing performance.
In simple terms, it’s timber selected specifically for structural reliability.
This means:
Exceptional strength and rigidity
Reduced movement over time
Long-term structural integrity
A solid framework you can trust
It forms the backbone of your building and ensures your investment stands the test of time.
Insulation: Rockwool & PIR Performance System
Designed for year-round comfort. A garden room should be usable 365 days a year — and that starts with proper insulation.
We use a combination of Rockwool mineral insulation and high-performance PIR rigid insulation boards, carefully installed within the floor, walls and roof.
Rockwool Insulation
Excellent thermal performance
Outstanding sound reduction
Fire-resistant
Breathable and moisture resistant
PIR Insulation
Extremely high thermal efficiency
Slim profile to maximise internal space
Long-lasting, stable performance
The result is a space that stays warm in winter, cool in summer, and comfortable every day in between — while helping to reduce energy costs.
Doors & Windows: Double Glazed Units
Light-filled and energy efficient.
All doors and windows are fitted with high-performance double glazing. Two panes of glass with an insulating gap help retain heat and reduce outside noise.
You benefit from:
Improved temperature control
Reduced heat loss
Lower energy consumption
A quieter internal environment
Natural light without compromising comfort.
External Finish: Thermowood Cladding
Beautiful. Durable. Sustainable.
We clad our garden rooms in premium Thermowood — a specially heat-treated timber designed for superior durability and stability.
The heat treatment enhances resistance to:
Moisture
Rot
Warping and movement
It’s treated without harsh chemicals and provides a clean, modern aesthetic that ages beautifully over time.
This is where performance meets design.
Interior Finish: Plasterboard Walls
A true extension of your home.
Inside, we finish your garden room with plasterboard walls — just like a traditional home extension.
This creates:
Smooth, paint-ready surfaces
A solid, permanent feel
A high-quality interior finish
The result is a space that feels integrated, warm and professionally built — not temporary.
roofing system: epdm rubber roof
Long Term protection from the elements.
Your garden room is protected with a single-piece EPDM rubber membrane — a highly durable roofing system widely used on modern flat roofs.
EPDM is designed to withstand::
Heavy Rain
UV Exposure
Extreme temperature changes Cracking or splitting
With a lifespan measured in decades, it provides low-maintenance, long-term protection and peace of mind..
Built Once. Enjoyed for Years.
Every Ewell Garden Room is constructed using materials and methods that prioritise durability, efficiency and comfort.
From the foundations to the roof, we build properly — so you can enjoy a space that performs just as beautifully as it looks.
