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Services · Wallingford, Oxfordshire

Garden Rooms Built Turnkey in Wallingford and South Oxfordshire

Base, frame, insulation, cladding and electrics handled as one job: a warm, dry, year-round room at the end of the garden, delivered on a fixed price rather than a running total.

Get a Free Fixed-Price Quote07462 376053

Ten years on the tools · £2m public liability insurance · fixed-price quote back within 72 hours

  • 10 years

    on the tools in finish carpentry

  • £2m

    public liability insurance

  • NVQ Level 2

    carpentry and joinery qualified

  • 72 hours

    to a written fixed-price quote

  • CAD drawings

    approved before anything is built

Recent work

Albums from our Oxfordshire portfolio

Fitted sage green wardrobes built into a sloping eaves bedroom with open shelving, Wallingford
Fitted Wardrobes & Bedroom Storage18 photos
Fitted cream bookcase with oak shelves and panelled base cupboards, doors open to show storage
Bookcases, Alcoves & Shelving17 photos
Bespoke green media wall with lit display shelving, panelled back and TV recess
Media & TV Units8 photos
View the full gallery

Overview

What a proper garden room is

A garden room is an insulated, weather-tight timber-framed building designed for year-round use: an office, a studio, a gym or a guest space. It is not a summerhouse with a heater in it. The difference is in the parts you never see: a level, well-drained base, a breathable and airtight wall build-up, insulation through floor, walls and roof, and a properly specified electrical supply.

We build them turnkey. That means one point of contact from the first survey to the day you plug a laptop in: groundworks and base, timber frame and structure, insulation and membranes, roof covering, cladding, windows and doors, internal linings, second fix carpentry and the electrical fit-out through trusted trades.

Because so much of the value is hidden in the build-up, we set the specification out clearly at quote stage. You will know the insulation, the membranes, the cladding, the roof covering and the electrical scope before you commit.

Garden rooms fail at the boring details: a base that holds water, a vapour control layer in the wrong place, cladding fixed without a drainage cavity, or an undersized electrical supply. Those faults show up in the second winter as condensation, mould and cold floors, and by then they are buried behind finished linings.

Who it's for

  • People working from home who need a separate room with a door that closes
  • Anyone who has run out of space indoors but does not want the cost and disruption of an extension
  • Gym, studio, therapy room and hobby space owners who need power, light and heat all year
  • Homeowners wanting usable guest or teenage space without changing the main house

When it's needed

  • The spare room is doing three jobs and none of them well
  • An existing shed or summerhouse is damp, cold and unusable from October to April
  • You need dedicated, quiet space for work calls away from the house
  • You want additional usable floor area without the planning and disruption of a full extension

The risk

Where cheap garden rooms go wrong

The most common failure is moisture. A wall built without a ventilated cavity behind the cladding, or with the vapour control layer on the wrong side of the insulation, will trap water vapour inside the build-up. It condenses when the temperature drops, soaks the insulation and eventually the frame. From the outside the building looks fine for two or three years; inside, the timber is quietly rotting.

The second is the base. A slab or bearer system laid on soft ground without proper compaction and drainage moves. Doors then stop closing, the floor develops a slope, and the junction between the frame and the base opens up. Correcting a failed base means lifting the building.

The third is electrical scope. A single extension lead trailed from the house is not a supply for a room with heating, lighting, a computer and a kettle. A garden room needs a correctly sized, buried armoured supply with its own protection, designed and certified, not improvised.

The last is running cost. An under-insulated room with single glazing costs a fortune to heat, so it does not get used from November onwards. The insulation spend is the cheapest part of the whole project and the one that decides whether the room earns its money.

Common mistakes we're called in to fix

  • Choosing on price per square metre without comparing insulation, glazing and roof specification
  • Laying a base straight onto topsoil with no compaction or drainage
  • Omitting the ventilated cavity behind cladding, so the boards never dry out
  • Running the power from an extension lead instead of a designed, buried supply
  • Assuming planning permission is never required, without checking size, height and boundary distance

Our process

How a garden rooms project runs, step by step

  1. 1

    Site survey and feasibility

    We visit the garden, check levels, ground conditions, access, boundary distances and where a supply can be run from. We talk through use, heating, glazing and whether the intended size and height sit within permitted development.

  2. 2

    Design, specification and fixed-price quote

    You get a layout and elevation drawing along with a written specification covering base type, frame, insulation, membranes, cladding, roof, glazing and electrical scope, with a fixed-price quote returned within 72 hours.

  3. 3

    Groundworks and base

    Ground is cleared and compacted, drainage considered, and the base installed, concrete slab or a screw-pile and steel or timber bearer system depending on ground conditions and access.

  4. 4

    Frame, weathering and services

    Timber frame erected, roof covered and made weather-tight, breather membrane and ventilated cavity formed, cladding fixed, windows and doors installed. Armoured supply run, first fix electrics installed by the dedicated electrician we work with.

  5. 5

    Insulation, lining and finish

    Full insulation to floor, walls and roof with the vapour control layer correctly positioned, internal linings, second fix carpentry, decoration, flooring, and electrical second fix and certification.

  6. 6

    Testing, snagging and handover

    Doors and windows adjusted and checked for seal, electrics tested and certified by the electrician, external drainage checked, site cleared and waste removed, then a walk-round and snag list completed with you.

What you get

The difference this makes, in specifics

  • Usable in January, not just July

    Insulated floor, walls and roof with correctly positioned membranes and double glazing mean the room holds heat and stays dry through an Oxfordshire winter.

  • One contractor, one programme

    Groundworks, carpentry, roofing, cladding and electrics are coordinated by us, so nobody is waiting on anybody and there is a single point of responsibility.

  • A fixed price, not a running total

    The specification and the price are agreed in writing before we start, and the quote comes back within 72 hours of the survey.

  • Extra room without extension disruption

    The build happens outside the house. Your kitchen stays a kitchen, there is no scaffolding against the property and daily life carries on.

  • Built for the ground it stands on

    Base type is chosen after looking at your ground conditions and access, not applied as a default, which is what stops doors sticking and floors sloping in year three.

  • Insured, qualified workmanship

    £2m public liability insurance, NVQ Level 2 carpentry and joinery, ten years of experience, with electrical work certified by the dedicated electrician we work with.

In detail

Build-up, materials and options

The specification is where garden rooms differ most from one another. This is what we build and why.

Base options

Concrete slab bases suit most level gardens with reasonable access: a compacted sub-base, membrane, insulation where the floor build-up allows, and a reinforced slab. They are stable, permanent and forgiving of heavy internal loads such as gym equipment.

Screw-pile and bearer systems suit sloping gardens, softer ground, restricted access and sites where you would rather not bring concrete through the house. They also lift the structure clear of the ground, which helps with drainage and airflow beneath the floor.

Either way, drainage matters. Water shed off the roof needs somewhere to go that is not the base perimeter, so guttering and a soakaway or drainage channel are planned in from the start.

  • Reinforced concrete slab on a compacted sub-base
  • Screw piles with steel or timber bearers for sloping or soft ground
  • Perimeter drainage, guttering and soakaway planned at design stage

Wall and roof build-up

Walls are a treated timber stud frame, insulated between and, where the design allows, over the studs to reduce cold bridging. A vapour control layer sits on the warm side of the insulation and a breather membrane on the cold side, with a ventilated and drained cavity behind the cladding so the boards can dry from both faces.

Roofs are built either as a warm flat roof, insulation above the deck, covered in GRP resin or single-ply, or as a pitched, hand-cut roof where the design calls for it. Both are detailed with proper upstands, drips and edge trims, because roof edges are where flat roofs leak.

Cladding and external finish

Cladding options include western red cedar, thermally modified timber, larch and composite boards. Cedar and thermally modified timber weather to a silver-grey if left untreated and are stable in changeable weather; larch is a cost-effective softwood option; composite avoids maintenance entirely at the expense of the timber look.

Whatever the board, it is fixed to battens over a breather membrane with a drainage gap behind, and end grain is sealed at cuts. That single detail does more for cladding life than the choice of timber.

Glazing, doors and layout

Most garden rooms use a set of sliding or French doors plus one or two windows. Glazing area is a balance: more glass means more light and a better connection with the garden, but also more heat loss and more solar gain on a south-facing elevation. Orientation, overhang and glazing spec are worth ten minutes of discussion at design stage.

Internally the layout usually splits between a main room and a small store or utility bay, somewhere for the consumer unit, heating unit and garden equipment so the main space stays clean.

Electrics, heating and use

The supply is normally a buried SWA cable from the house consumer unit to a small consumer unit in the garden room, sized to the intended load and installed and certified by an electrician. From there: lighting, sockets, data, and a heating solution, usually an electric panel heater or an air conditioning unit that also provides heat.

Think about the end use early. A gym needs a robust floor build-up and more sockets than you expect. An office needs data and good daylight without screen glare. A studio may need higher ceilings or specific lighting. These change the build, and they are cheap to accommodate at design stage.

Planning and building regulations

Many garden rooms fall within permitted development, but that depends on height, footprint, proximity to boundaries, whether the property is listed or in a conservation area, and how the building is used. Sleeping accommodation changes the position entirely and normally brings building regulations into play.

We flag anything that looks likely to need consent at survey stage so you can check with South Oxfordshire District Council before committing. We would rather raise it early than build something that has to be altered.

Questions

Garden Rooms: the questions we're asked most

How much does a garden room cost?
Garden room cost is driven by footprint, base type, glazing, cladding and electrical scope, so each build is priced individually rather than against a headline figure. We return a written fixed-price quote within 72 hours of the survey, with the full specification set out.
How long does a garden room take to build?
Garden room build time is typically around six weeks lead time from order, with the on-site build itself usually running a few weeks depending on size, base type and weather. A full programme is provided with the quote.
Do I need planning permission?
Planning permission for a garden room depends on its height, footprint, boundary distance, conservation area status and intended use, though many fall within permitted development. Sleeping accommodation changes the position significantly, and we flag anything likely to need consent at survey stage so you can confirm with the council.
Can I use it all year round?
A garden room built to our specification is designed for year-round use, with insulation to floor, walls and roof, correctly positioned membranes, double glazing and a designed heating solution keeping it comfortable through an Oxfordshire winter without excessive running costs.
How is the electricity supplied?
Electricity to a garden room is normally supplied via a buried armoured cable run from the house to a small consumer unit inside the room, sized for the intended load and installed and certified by the dedicated electrician we work with.
How long will a garden room last?
A garden room built with a properly designed base, ventilation and detailing is a long-term structure rather than a short-life outbuilding. The maintenance items are the external finish and roof covering; the frame and insulation are protected by the membranes and drainage cavity behind the cladding.
What maintenance does it need?
Garden room maintenance is limited to clearing the gutters, keeping the drainage path around the base free, and re-treating the cladding if you want to hold its original colour. Cedar and thermally modified timber can also be left to silver naturally with no treatment at all.
Do you handle the groundworks and base too?
Groundworks and the base are included in our turnkey garden room service, alongside the frame, roof, cladding, insulation, internal finish and electrics, all managed by us through our own work and trusted trades.
Is there a guarantee?
There is no formal written guarantee on garden room builds at present. CZ Bespoke Carpentry carries £2m public liability insurance, Corey is NVQ Level 2 qualified with ten years' experience, and electrical work is certified by the installing electrician.
Which areas do you build garden rooms in?
Garden rooms are built across Second fix carpentry covers Wallingford, Goring, Streatley, Moulsford, Cholsey, Ipsden, Harwell, Henley, Woodcote, Didcot, Abingdon, Benson, Crowmarsh Gifford, Watlington, Nettlebed and the surrounding South Oxfordshire villages.

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Where we fit garden rooms

Free site visits across South Oxfordshire and the Chiltern villages:

Get your garden room specified and priced

Tell us the size you have in mind and what the room is for. We will survey the garden, set out the full specification and return a fixed price within 72 hours.

Get a Free Fixed-Price Quote07462 376053

Corey Holleran · NVQ Level 2 qualified · £2m public liability insurance · quotes back within 72 hours

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