Greenhouse Combi Sheds UK: Half Greenhouse, Half Storage Buyer's Guide
Greenhouse combi sheds give you secure storage and a growing space in a single building. Our team installs Swallow ThermoWood combis across the UK every week. Prices start at £4,082 for the Kingfisher 6x6 model, with free delivery and installation. One combi typically saves 30-40 percent of the ground footprint compared with a separate shed and greenhouse on the same plot.
Key Takeaways
- Two buildings in one: A combi shed gives you a lockable storage compartment and a glazed growing space on a single base.
- Footprint saver for small gardens: An 8x10 combi typically replaces a separate 6x4 shed plus 6x8 greenhouse - about 38 sq ft of garden saved.
- Swallow uses ThermoWood, not cedar: Heat-treated Scandinavian redwood with a 12-year frame guarantee and a 25-year service life in our experience.
- Five UK models covered here: Kingfisher 6x6, Kingfisher 6x8, Raven 8x6, Raven 8x10, plus the Jay 6x6 Painted potting shed.
- Prices £4,082 to £5,810: Every Swallow model in our range ships with free UK delivery and factory-trained installation.
- Best for plots under 8 metres wide: Where a separate shed and greenhouse would crowd the borders.
Installer's Note
I'm Matt. My team has installed Swallow combi greenhouses across the UK for over a decade. Of every customer who first asked about a separate shed and greenhouse, around three in five switched to a combi after we walked the garden together. The reason rarely changes. Mark out two buildings on the ground and you lose a path between them, a planting border, and often a useful corner of the lawn. The combi solves all three in one base. It also halves the time on site. A 6x8 Kingfisher Combi is a two-day install for two fitters. Two standalone buildings on the same plot take three to four.
What is a greenhouse combi shed?
A greenhouse combi shed is one timber-framed building split internally into two compartments. One end is a fully glazed greenhouse with staging and ventilation. The other end is a clad, lockable shed with a solid door. An internal partition - sometimes with its own door, sometimes solid - separates the two sides.
The Swallow wooden greenhouses range we install in the UK is built around three model families:
- Kingfisher - 6ft wide combi, sized for small to medium gardens.
- Raven - 8ft wide combi for larger plots and serious growers.
- Jay - the pure potting shed variant, glazed at the front only with full storage behind.
All three use the same Scandinavian ThermoWood timber and the same hand-built joinery. The difference is the ratio of glass to cladding. A Kingfisher Combi is roughly two-thirds greenhouse to one-third shed. A Jay is the opposite - mostly shed with a single glazed front for light and pelargoniums.
How much footprint does a combi shed save vs separate buildings?
Here is the maths from our own installs. A typical "separate" setup on a medium UK garden is a 6x4 metal shed (24 sq ft) plus a 6x8 aluminium greenhouse (48 sq ft). Total ground used: 72 sq ft, before paths.
You also need a working gap on each side. We allow 600mm minimum between buildings for access. That adds another 18-24 sq ft of "lost" garden - paving, gravel or trampled grass.
A Swallow Kingfisher 6x8 Combi gives you a 6x4 shed plus a 6x8 greenhouse footprint, but as one building with one base. Total ground used: 48 sq ft. No access gap needed between the two halves. The customer keeps roughly 25-40 sq ft of garden compared with the separate option.
| Setup | Footprint | Access gaps | Total ground used |
|---|---|---|---|
| 6x4 shed + 6x8 greenhouse, separate | 72 sq ft | ~22 sq ft | 94 sq ft |
| Swallow Kingfisher 6x8 Combi | 48 sq ft | 0 sq ft | 48 sq ft |
| 8x6 shed + 8x10 greenhouse, separate | 128 sq ft | ~28 sq ft | 156 sq ft |
| Swallow Raven 8x10 Combi | 80 sq ft | 0 sq ft | 80 sq ft |
On the larger plot, the Raven 8x10 Combi saves around 76 sq ft of garden ground - the size of a child's trampoline.
Who is a combi shed best for?
From years of customer conversations, four buyer profiles come up again and again.
- Owners of small UK gardens (under 8 metres wide). They want both functions but cannot lose the lawn or borders to two separate buildings.
- First-time greenhouse owners who already have an ageing metal shed they want to replace. Combining the upgrade saves money and time.
- Older gardeners downsizing from an allotment. The combi keeps a workshop area for repotting and a growing area in arm's reach.
- Anyone wanting a single attractive timber building rather than a mismatched shed-and-greenhouse pair. Many of our customers cite the look as the deciding factor.
If your plot is wider than 9 metres and you need a workshop big enough for a bike, a mower and a freezer, a separate shed plus a freestanding glasshouse may suit better. Our potting shed vs greenhouse comparison walks through that decision in detail.
Wooden vs aluminium combi sheds: which lasts longer?
Aluminium combi sheds exist - typically apex potting sheds with a glazed roof and 4ft solid sides. They are cheaper, starting around £900 for the Power range we stock. The frame will not rot and assembly is faster. The trade-off is heat loss in winter, condensation drip in spring, and a much shorter useful life on the shed side. Powder-coated steel panels begin to corrode at the cut edges within 7-10 years on a typical UK garden.
A timber combi - specifically ThermoWood - lasts considerably longer. We have customer photos of 18-year-old Swallow buildings on our books that still look new with nothing more than an annual oil refresh. The shed compartment stays warmer in winter, which matters if you store sensitive items like battery tools, paint or seed potatoes.
The rule we give every customer: buy aluminium if budget is under £1,500 and you only need 5-7 years of service. Buy timber if you plan to be in the house for a decade or more.
Inside the shed compartment looking through to the growing side - one base, one roof, two jobs.
Why Swallow combi sheds are the UK benchmark
Three things set Swallow apart, and I say this as someone who fits them alongside other brands every week.
The timber is ThermoWood, not cedar
Lots of buyers ask us if Swallow buildings are cedar. They are not. Swallow uses Scandinavian redwood, heat-treated in oxygen-controlled ovens to around 215°C. The process bakes out the sugars and resin that fungi feed on. The result is a stable, rot-resistant timber. It has the warm honey colour cedar buyers expect, at roughly half the raw timber cost. Outdoor service life is also longer than untreated cedar.
ThermoWood comes with a 30-year above-ground rot warranty from the timber mill. Swallow's frame guarantee runs 12 years.
Hand-built joinery, not flat-pack panels
Every Swallow combi I have installed arrived on a flat-bed lorry as individual numbered sections built in their North Yorkshire workshop. The corner joints are mortice-and-tenon. The door frames are housed. The glass is bedded in linseed putty exactly like a Victorian greenhouse. Nothing is screwed-on plywood. This is why the buildings last so long.
Free installation by factory-trained fitters
Every Swallow combi we sell ships with free UK installation by Swallow's own factory-trained team or our partner installers. That is unusual at this price point. A separate timber shed and greenhouse from competing suppliers will typically cost £800-£1,400 in installation labour on top.
ThermoWood close-up - the heat-treated Scandinavian redwood used on every Swallow combi.
The five UK combi models we fit most often
Here are the five Swallow models we install and recommend, in size order.
Swallow Kingfisher 6x6 Combi - £4,082
The entry point to the combi range. A 4ft shed compartment with a 6ft glazed growing area. Best for very small gardens where every square foot counts. We fit a lot of these into terraced and Victorian semi gardens around London and Manchester. The footprint matches a standard 6x10 metal shed but gives you both functions.
Swallow Kingfisher 6x8 Combi - £4,278
The most popular size we sell. A 4ft shed plus a 6ft greenhouse compartment in a single 6x10 building. Roomy enough for a 6ft potting bench on the shed side and three rows of tomatoes on the glazed side. This is the size we recommend to first-time buyers if their plot allows it.
Swallow Raven 8x6 Combi - £5,030
Step up to 8ft width and the building changes character. The Raven 8x6 has a wider greenhouse compartment with room for a central walkway and staging on both sides. Easier to work in than the Kingfisher. Best for gardeners who plan to grow under glass year-round.
Swallow Raven 8x10 Combi - £5,810
The largest standard combi in the range. A 4ft shed plus an 8ft greenhouse compartment in one 8x14 building. Big enough to fit a sit-down propagation bench and serious storage at the same time. Most of our Raven 8x10 installs are for retired gardeners with a long, narrow garden.
Swallow Jay 6x6 Painted Potting Shed - £4,399
Not a full combi but worth covering here. The Jay is Swallow's pure potting shed - storage at the back, a single glazed front for light and a wide internal potting bench. It is the right choice if you want shelter for transplanting and seed-starting, but do not need to grow tomatoes or cucumbers indoors. The painted finish adds a softer cottage-garden look.
Matt's Tip: Pick your combi by use, not by price
People often size up a combi on cost per square foot. That misses the point. The shed side and the greenhouse side serve different jobs. If you plan to grow heat-loving crops, prioritise the greenhouse compartment - go Raven 8x6 or Raven 8x10 even on a smaller plot. If your main need is dry, lockable storage with a small growing area, the Kingfisher 6x6 or 6x8 is the better fit. Walk the garden first with a tape measure and a rough plan of what each side needs to hold.
Matt's Pick for the Best All-Round Combi
Best For: Narrow plots that want a longer growing run. The 6x10 has the storage of a 6x6 with double the glass.
Why I Recommend It: It's our sweet spot for keen growers on small UK plots. The 8ft greenhouse end gives you a proper run of staging for tomatoes and cucumbers. The 4ft shed end still swallows a mower and a wall of tools.
Price: £4,520
What to expect on installation day
A Swallow combi is delivered on the morning of fit, in pre-built numbered panels. Two fitters spend the first hour checking the base. If you have a level concrete slab or paving, fitting starts immediately. If the base is uneven, we use composite levelling shims rather than packing timber underneath.
The shed compartment goes up first, then the greenhouse end, then the partition wall. Glazing is bedded in linseed putty as each section goes in. Doors, windows and vents are fitted last. Most 6ft Kingfisher Combis are watertight by the end of day one. Larger Ravens take a second day for glazing and final adjustments.
One thing we always tell customers: clear a path at least 1 metre wide from the access gate to the build location. The longest pre-built panel on a Raven 8x10 is 2.4 metres and needs that space to carry round corners.
Combi shed vs potting shed: which one do you actually need?
The wording confuses a lot of buyers, so worth being clear. A combi shed is split half storage, half greenhouse. A potting shed, in Swallow's language, is the Jay - mostly storage with a glazed front for working at a bench in natural light. They look similar from outside but you cannot grow tomatoes in a Jay.
If you want a shelter to transplant seedlings, sharpen secateurs, and store the mower, get a potting shed. If you want all of that PLUS a glazed compartment to grow tomatoes, cucumbers or chillies under glass, get a combi.
For workspace layout inside, our potting shed ideas guide covers bench height, tool rails and shelving. Our potting shed accessories roundup lists the eight items we fit on every install.
Bases and groundwork
Every Swallow combi needs a level base before we can fit it. The base must match the building footprint exactly, with a maximum tolerance of 10mm over the full length. We accept three base types: concrete slab, paving slabs on a Type 1 hardcore sub-base, or timber-framed dwarf walls infilled with paving.
If your plot is on a slope, plan a retained level area before we deliver. A local groundwork firm can typically build a Type 1 base for a 6x8 combi in a day. UK pricing is around £400-£600. Our greenhouse roof shapes guide covers how combi roofs differ from standard apex.
Storage capacity: what fits in the shed side?
The 4ft shed compartment on Kingfisher and Raven combis offers around 4ft x 6ft of floor area. From our installs, that holds:
- A standard ride-on mower with deck down (snug fit on Raven only).
- A push-mower, strimmer, leaf-blower and full wall of hand tools on hooks.
- A 6ft potting bench along one wall plus 2 metres of shelving above.
- Battery and fuel storage in a lockable steel cabinet beneath the bench.
If you need to fit two adult bikes plus the mower, a 4ft combi compartment will be too small. Look at the 6ft shed combination upgrades Swallow offers. Or pair the greenhouse with a separate storage building.
Year-round use: what to grow in the greenhouse side
A 6x6 or 6x8 Kingfisher gives you enough glazed space for a respectable UK greenhouse year. We hear back from customers growing tomatoes, cucumbers and aubergines through summer, then overwintering pelargoniums, fuchsias and tender herbs into spring. For a month-by-month UK planting calendar tailored to compact growing spaces, see our monthly growing guide.
The 8ft Raven compartments let you add a heated propagator on one side and still walk between staging benches. We have customers in Yorkshire and Scotland who hold their Raven greenhouse compartment frost-free with a single 2kW tubular heater through winter. The timber walls hold heat much better than aluminium.
How long does a Swallow combi shed last?
From our own customer records, a Swallow ThermoWood combi installed in 2008 is still sound today. It has been re-oiled twice in 17 years. The mill warrants the timber against above-ground rot for 30 years. The frame carries a 12-year guarantee. Glass is toughened on request.
Annual maintenance is light. One coat of Swallow's recommended timber oil every two to three years. A check of door catches and partition hinges each spring. A wash of the glass twice a year. That is genuinely all.
Why choose Greenhouse Stores for your combi
We have been fitting greenhouses across the UK since 2012. We have sold combi sheds since they first appeared in the Swallow range. Every combi includes factory-trained installation, a 12-year frame guarantee, and our own after-sales support. To browse the full range, visit Greenhouse Stores or jump to our greenhouse combi sheds collection page.
Frequently asked questions
What is a greenhouse combi shed?
A combi shed is one timber building split internally into a shed and a greenhouse. The two compartments share a base, a roof and a partition wall. One end is clad and lockable for storage. The other end is glazed for growing. Most UK combi sheds have a 4ft shed compartment and a 6ft, 8ft or 10ft greenhouse compartment.
How much does a greenhouse combi shed cost in the UK?
UK timber combi sheds start around £4,000 fitted and rise to £7,000 for larger models. Swallow ThermoWood combis price from £4,082 for the Kingfisher 6x6 to £5,810 for the Raven 8x10. Free UK delivery and installation are included on every Swallow combi.
Is a combi shed better than a separate shed and greenhouse?
For most UK gardens under 8 metres wide, a combi shed saves money, ground space and installation time. One combi typically uses 30-40 percent less garden footprint than a separate shed plus greenhouse. No access gap is needed between buildings. On larger plots needing a serious workshop and a walk-in growing house, two separate buildings can be right.
What are Swallow combi sheds made from?
Swallow combi sheds are built from Scandinavian ThermoWood, not cedar. The timber is heat-treated to around 215°C in oxygen-controlled ovens. The process makes it rot-resistant for 30 years above ground. It has a warm honey colour, takes oil or paint well, and is more stable than untreated softwood or cedar.
How long does a Swallow combi take to install?
A 6ft Kingfisher Combi takes one day for two fitters with a level base ready. An 8ft Raven Combi takes one and a half to two days. We arrive with all pre-built panels on a flat-bed lorry. We glaze on site with linseed putty bedding. The building is left watertight on the final day.
Do I need planning permission for a combi shed in the UK?
Most domestic combi sheds fall under permitted development rights and do not need planning permission. Limits to watch: total outbuilding coverage must stay under 50 percent of your garden, eaves under 2.5 metres if within 2 metres of a boundary, and total height under 4 metres. Listed buildings and conservation areas have separate rules - check with your local planning office first.
Can I fit a combi shed myself?
You can, but Swallow combis are designed to be installed by factory-trained fitters. Self-assembly voids the 12-year frame guarantee on most Swallow models. Installation is included free with every combi we sell. There is no cost saving to doing it yourself, only the loss of warranty cover.
