01
Home Office
3×3m to 4×3m footprint, one full-width glazed elevation, cabled for two workstations, acoustic plasterboard to keep video calls quiet. The most common brief we build.
Extensions
Garden Rooms & Studios in London & the Home Counties
Signature detail
The insulated envelope
What separates a real garden room from a glorified shed is the envelope. 150mm of PIR (or structural SIPs) to walls, floor and roof brings the whole-building U-value down to 0.18 W/m²K — the same standard as a new-build home. Combined with argon-filled A-rated glazing and a taped, membrane-sealed shell, the room holds temperature overnight on a single panel radiator through a British winter. That's the difference between a room you use every day and a room you use in July.
Overview
A garden room is a proper room — SIPs or PIR-insulated, mains-powered, heated, and finished to the same standard as the main house. Home offices, gyms, studios, treatment rooms and guest snugs, engineered to be used every day of the year rather than a summer shed at the end of the lawn.
Specification
Structural timber or SIPs frame · 150mm PIR insulation · EPDM or standing-seam aluminium roof · Cedar, Accoya, painted-timber, composite or aluminium cladding · thermally-broken aluminium glazing · engineered oak, LVT or polished-concrete floors
01
Fully Insulated Envelope
150mm PIR or structural SIPs to walls, floor and roof — whole-building U-value 0.18 W/m²K, comfortable in December and cool in July with no bolt-on air-conditioning.
02
Mains-Powered & Wired
Dedicated RCD-protected consumer unit, ring main, data (Cat6), lighting circuits and optional networked heating — all buried in armoured SWA from the main house by our own electricians.
03
Heated Year-Round
Panel radiators, low-profile electric underfloor heating or an air-source heat pump — sized to the space so it runs on a fraction of the energy demand of a poorly insulated conservatory.
04
Bespoke Cladding
Western Red Cedar, thermally-modified Accoya, painted timber, composite or standing-seam aluminium — matched to the palette of your house and garden, not pulled from a catalogue.
05
Large Aperture Glazing
Full-width aluminium bifolds, slim-frame sliders or fixed picture panes up to 2.7m tall — the front elevation opens the room to the garden the way a summer house never could.
06
Permitted Development
Most builds fall under PD as an outbuilding: under 2.5m at the eaves, under 3m ridge (pitched roof further than 2m from any boundary). We survey, confirm and, where needed, obtain a lawful development certificate on your behalf.
07
Turnkey, Single-Point Delivery
Design, foundations, frame, cladding, glazing, electrics, plastering, flooring and decoration — one contract, one named site manager, one aftercare number. No sub-let trades, no gap in accountability.
08
Plumbed on Request
WC, shower or utility sink runs off the house cold main and drains into the nearest inspection chamber — specified at survey for treatment rooms, gym showers and guest snugs.
Specification
Engineered to the millimetre.
Every frame we install is made to your survey sizes with the following performance envelope as standard.
- Whole-building U-value
- 0.18 W/m²K (walls, floor & roof)
- Glazing U-value
- 0.9 – 1.4 W/m²K argon-filled A-rated
- Typical footprint
- 3×3m up to 8×5m single-storey
- Ridge height (PD)
- ≤ 2.5m eaves · ≤ 3.0m ridge
- Electrical spec
- Dedicated CU · SWA feed · Cat6 · Part P certified
- Guarantee
- 10-year insurance-backed workmanship · 25-year cladding
- Typical timeline
- 2–4 weeks on site · 6–8 weeks survey-to-handover
Ranges & styles
The garden rooms family.
Every one of the following styles is available in the garden rooms range — mix, match and specify at survey.
02
Garden Studio
Artist, yoga or music studio — north-light glazing, extra ceiling height where the roof pitch allows, oak or resin floor, and independent thermostat so it holds temperature overnight.
03
Gym & Treatment Room
Reinforced floor deck for weight equipment, ventilated changing area, optional plumbed shower and WC. Mirrored end wall available with laminated safety-backed glass.
04
Guest Snug
Insulated to Building Regs habitable standard where used for occasional overnight stays, with a small kitchenette and shower room. We advise on the PD-versus-outbuilding distinction at survey.
05
Pool House
Ventilated, moisture-managed envelope with dedicated dehumidifier connection — the right specification for a pool or hot-tub building that would otherwise rot a standard shed within a decade.
From enquiry to aftercare
A calm, predictable process.
No sales calls, no pressure, no surprises. Every project follows the same six steps — with a named surveyor from start to finish.
- 01Week 1
Design consultation
A senior surveyor visits, measures the plot, discusses use, orientation and access, and sketches options around your preferred use and finish.
- 02Week 1–2
Detailed proposal
Cladding, glazing, electrics, heating and decoration are itemised clearly, with no showroom pressure.
- 03Week 2–4
Planning & compliance
We confirm permitted development or, where needed, prepare and submit a lawful development certificate. Building Regs handled where the space is habitable.
- 043–5 days on site
Groundworks & foundations
Screw-pile or concrete-pad foundations installed to the surveyor's spec — minimal garden disturbance and no need for a full slab on most sites.
- 051–2 weeks on site
Frame, cladding & glazing
Timber or SIPs frame erected, PIR insulation, breather membrane, cladding and roof laid — the shell weathertight within a week.
- 061 week on site
Second fix & handover
Electrics, plumbing, plastering, flooring, decoration, snag walk and 10-year insurance-backed guarantee.
Garden Rooms — where we install
Garden Rooms across London
and the Home Counties.
We install garden rooms across six counties — every project surveyed, made and fitted by our in-house team. Choose your county to read local knowledge, planning notes and recent work.
See all areas coveredGarden Rooms in LondonAll Greater London boroughsGarden Rooms in BuckinghamshireAmersham to AylesburyGarden Rooms in HertfordshireSt Albans to Hemel HempsteadGarden Rooms in BedfordshireLuton to BedfordGarden Rooms in NorthamptonshireNorthampton to KetteringGarden Rooms in OxfordshireOxford to Banbury
Recent work
Garden Rooms — installed.
A selection of recent installations across London and the Home Counties, photographed on site.
Common questions
Practical answers.
Everything homeowners ask us about garden rooms — survey, lead times, guarantees and coverage.
Do I need planning permission for a garden room?+
Usually not. Under permitted development, an outbuilding under 2.5m tall at the eaves (or up to 3m ridge if further than 2m from any boundary), not occupying more than 50% of the original garden and not in front of the principal elevation, is permitted. Listed buildings, conservation areas and Article 4 zones need full planning — we handle the application on your behalf.
How long do they take to build?+
A typical garden room is weathertight within 7–10 days on site and complete in 2–4 weeks from ground-breaking, depending on size, cladding and internal finish. Complex pool-house or plumbed builds run 4–6 weeks.
Can I use it as a bedroom or Airbnb?+
Occasional overnight use falls under PD as an outbuilding. Regular sleeping accommodation or short-let use makes it a habitable dwelling — Building Regs apply, potentially planning too, and Council Tax implications need advice. We flag the distinction at survey and won't build outside the rules.
How is it heated?+
Panel radiators, low-profile electric underfloor heating, or an air-source heat pump. Because the envelope is insulated to 0.18 W/m²K, energy demand is substantially lower than a poorly insulated conservatory — a 4×3m office holds temperature on a 500W panel through a British winter.
Do I need foundations?+
In most cases, screw piles or ground screws — installed in a day, no concrete pour, no soil disturbance, and fully reversible if the garden ever needs to be restored. On soft ground or larger builds we use engineered concrete pads. We survey the ground before quoting.
What cladding lasts longest?+
Thermally-modified Accoya (Class 1 durability, 50-year warranty), composite (25-year colour warranty) and aluminium standing-seam (30-year+) all outlast cedar (15–25 years silvered). Cedar is the classic choice; if you want no maintenance ever, specify Accoya or aluminium.
Can it be plumbed?+
Yes — a WC, shower and utility sink run off the house cold main and drain into the nearest inspection chamber, provided levels allow. We survey the drainage run at design stage; on tricky sites a Saniflo-style macerator makes it possible where gravity won't.
Does it add value to the house?+
A well-built, insulated, year-round garden room typically adds 5–8% to the value of a family home in the Home Counties — significantly more than a summer house or shed. It reads as usable floor area in an estate agent's brief, provided the electrics are certified and the build is Part P compliant.
What guarantee do you offer?+
10-year insurance-backed guarantee on our workmanship, 25-year cladding manufacturer warranty (Accoya, aluminium and composite), and the standard glazing and hardware warranties. All transferable to a new owner.
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Garden Rooms.
Speak with our design team, book a home survey, and receive a fixed written quotation — all with no obligation.
Call · 020 3633 0405