Guides · Garden room guides
How a garden room is built for year-round use.
In short: A year-round garden room needs foundations suited to your ground, a well-insulated floor, walls and roof, heating sized to how you'll use it and a properly planned electrical supply. Those choices are made at design stage, because retrofitting them later costs far more.
What foundations does a garden room need?
Foundation choice depends mainly on your garden's ground conditions, and it's assessed on-site before the design is finalised.
Concrete base
A traditional poured concrete base or slab gives a solid, long-lasting foundation, well suited to most ground conditions, though it takes longer to cure before construction can continue.
Screw-pile foundations
Screw piles are quicker to install, cause less disruption to the surrounding garden, and work well on a range of ground types, though they're not always suitable depending on soil conditions, which we assess on-site.
Garden room roof options
Roof choice affects both how the garden room looks from the house and how it performs.
Flat roofs
A flat roof with a single-ply or felt membrane is the most common choice for a clean, modern look, and tends to be the most cost-effective option.
Pitched and green roofs
A pitched roof can suit a garden room designed to match the style of the main house more closely. A green (planted) roof adds visual interest and some environmental benefit, though it needs a structure designed to take the extra weight.
How is a garden room insulated for year-round use?
Insulation is what separates a proper garden room from a garden shed — here's what a well-specified build includes.
Floor, walls and roof
A well-built garden room insulates all three elements: an insulated floor over the foundation, insulated timber or SIPs-based wall panels, and a properly insulated roof structure. Skimping on any one of these tends to show up as a cold spot or condensation issue later.
Glazing and heating
Double or triple glazed windows and doors matter as much as the fabric insulation, since a garden room typically has more glazing proportionally than a house extension. Electric panel heaters or a small radiator system, sized to the room, complete a genuinely year-round space.
How is a garden room heated?
Heating choice usually comes down to how the room's used and how it's powered, more than personal preference alone.
Electric panel heaters
A common, straightforward choice for garden rooms already running on an electric supply from the house. Modern panel heaters are efficient and can be controlled individually or via a thermostat.
Small radiator systems
Where a garden room already has water services run to it (for a kitchenette or WC), a small radiator circuit can be a practical addition, though it adds plumbing complexity compared with electric heating alone.
What electrics does a garden room need?
Getting electrics right at design stage avoids expensive retrofitting later — here's what's typically involved.
Supply and circuits
Power is usually run from the main house's consumer unit via an armoured cable, sized appropriately for the garden room's expected load (heating, equipment, lighting). We check your existing consumer unit has capacity as part of the survey.
Sockets, lighting and data
Sockets and lighting circuits are planned around the room's use — more sockets for an office or gym, dimmable lighting for a bar. Network cabling is worth including for an office, giving more reliable connectivity than relying on Wi-Fi alone.
Frequently asked questions
How a garden room is built for year-round use: FAQs.
Which foundation type is better for a garden room?
It depends on your specific ground conditions and garden access — we assess this on-site and recommend the appropriate option for your project.
Is a green roof more expensive than a standard flat roof?
Generally, yes, due to the additional structural and waterproofing requirements, but it's an option we can design in if it suits your garden.
Can an existing summer house be insulated to the same standard?
Not usually without significant rebuilding — most summer houses aren't built with insulation-ready wall and roof structures, which is why a purpose-built garden room performs differently.
Is electric heating expensive to run in a garden room?
Running cost depends on usage and how well the room is insulated — a well-insulated garden room needs relatively little heating to stay comfortable.
Does garden room electrical work need certification?
Yes, electrical work must comply with Part P requirements and be carried out or certified by a competent, registered electrician.
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