Evolution 12 Greenhouses

  • Toughened glass
  • Sliding door
  • Free 10 Year Guarantee
  • Downpipes both sides
  • Low level threshold
  • Extremely strong frame
  • Western Red Cedar
  • Screw in cedar bar capping system
  • Installation available for a fee
Delivery in 4-6 weeks

Delay delivery for up to 12 months. Only a 25% deposit required today.

Configure & Buy

Click on a size below to view prices & buy or obtain a quote

dimensions logo


A = 3877mm (5'6")

B = From 1977mm to an unlimted length

C = 1700mm (5'6")

D = 2650mm (7'5")

E = 1190mm (2')

F = 1890mm (6'2")

Western red cedar

We select only the best Western Red Cedar, supplied from renewable sources as it's the ideal material for use in our greenhouses. Noted for its extraordinary durability, it doesn’t shrink, swell or warp excessively, and readily holds wood stains and micro-porous paints. It has prime insulating qualities and its pleasant aroma is naturally repellent to moths, insects and vermin.

finest-materialsAll of our unpainted greenhouses are factory-treated by total immersion in our Golden Honey cedar preservative prior to delivery which renders it virtually immune to decay, while our painted greenhouse options look stylish in any outdoor setting and are protected with micro porous paint.

If you wish to maintain the original warm, golden honey colour, we recommend you re-treat your frame annually. If not, the wood will gradually fade to its attractive natural appearance - varying from almost pure white of the narrow sapwood to the light straw shade of the heartwood. This will not affect your 10 year framework guarantee.

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Other features and options


Mortice and tenon joints.The Cleverly designed jointing system on the Evolution has the duel benefit of making assembly straight forward and adding strength to the framework.

Aluminium base - This keeps the wood well away from the base where water can sit. Plus this unique design feature allows the glass to sit directly onto the metal base - which means that the side water is not running onto the wood, (which is a 'rot-spot' on other greenhouses) The Metal base is included on every Evolution model, regardless of which kind of capping you choose.

Guttering Takes the water away and allows you to collect it. Included on every model regardless of which kind of capping you choose.

Roof vents. A generous allocation of roof vents is included with every model and every roof vent has an automatic opener included as standard. These clever devices work through heat expansion alone to open your roof vents gradually as the temperature changes. Fully adjustable, they help you to create the perfect growing environment.

Louvres Your new Alton Evolution model will also include one or more louvre windows. These work in tandem with your roof vents - as the automatic roof vents open and release the warm air, the greenhouse effectively sucks air in through the louvres. These can be positioned near the bottom or the top and on most models at the side of the greenhouse or at the rear. Supplied as manual opening as standard and you can add automatic louvre openers if you wish.

The unique Alton Evolution door system includes the low-profile door threshold. This popular feature means that you have no step at the door (many other greenhouses have a step at the door). Models of 8' wide and above have 4' wide access double doors which allow easy entrance for a wheelbarrow or wheelch

Upgrade option Aluminium bar capping - With this new Aluminium bar capping system you really can have a virtually maintenance free Cedar greenhouse - and the stylish moss colour blends in perfectly with the cedar as it ages to the distinctive silvery colour.

The eaves height of 5'7" on the Alton Evolution models is excellent and is as much as 18" higher than the lowest greenhouses on the market. The extra height gives you several advantages: There is more air in the greenhouse creating a better growing environment, you have more head room and a higher door, and you have plenty of room for a high level shelf in the greenhouse.

The Alton Evolution 12'9"greenhouse

Evo Twelve

Ideal for really large gardens, estates and nurseries, the Twelve is actually a generous 12ft 8 inches wide and can be built to any length. In addition, you can add one or more internal partitions with double doors which can  be used to create different environments within the greenhouse (and they add considerable strength to the greenhouse too.)

The Clever design of the Evolution Eight means that it is relatively easy to deliver (being flat packed) yet also reasonably straightforward to assemble and full instructions are included. (but don’t worry, if you want an expert fitter to assemble it for you, we have a network of fitters all over the UK)

The Alton Evolution Twelve includes Double doors, low level threshold, Toughened safety glass, Cedar bar capping, Aluminium guttering, Aluminium base plinth and automatic roof vents as well as louvre side vents.

You can also upgrade to the Aluminium bar capping if you want to reduce to almost maintenance free.



Click on an image or video to enlarge it

Alton Evolution Ten 12 x 6 Cedar Greenhouse Alton Evolution Twelve 12ft Alton Evolution Ten 12 x 20 Cedar Greenhouse Alton Evolution Ten 12 x 6 Cedar Greenhouse Evolution roof vent with auto opener Alton Evolution Ten 12 x 18 Cedar Greenhouse Alton Evolution Ten 12 x 6 Cedar Greenhouse Bar Capping set (Moss Green) for Evolution Twelve Alton Evolution Twelve 12 x 40 Cedar Greenhouse Alton Cedar Greenhouse Alton Evolution Twelve 12 x 14 Cedar Greenhouse Guttering and Downpipes both sides Alton Evolution Twelve 12 x 18 Cedar Greenhouse Louvre vent Metal base Alton Evolution Twelve Cedar Greenhouse

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