Plot & Pot

Roundups / Styrene greenhouses

Grow-your-own · UK product comparison

Best greenhouses with styrene glazing compared in 2026

Styrene is a common glazing choice for timber greenhouses, and this roundup covers six models that use it, priced from £479.99 to £779.99. Three are Mercia Traditional greenhouses in different sizes, and three are Evesham designs from Waltons, including a compact growhouse and a lean-to that sits against a wall. All are self-assembly timber builds. This is desk research based on the product details supplied, not hands-on testing.

P&P

Plot & Pot editors
We compare published product details, sizes and materials. These are desk-researched product roundups, not hands-on tests.

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Our stand-out pick

Mercia Traditional Greenhouse 8x6

The Mercia Traditional Greenhouse 8x6 is our pick on paper. At £679.99 it costs £100 less than the smaller Mercia 6x6 at £779.99, yet it has a bigger footprint of 192.8 x 240.7 cm and the same opening roof vent, hinged single door and styrene glazing. It is also the largest greenhouse in this group. The conditional 10-year anti-rot warranty needs annual retreatment, which is worth planning for. This choice comes from comparing the supplied facts, not from testing.

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At a glance

Our picks compared

Prices are dated snapshots and can change. Product dimensions are shown as width × depth × height.

ProductBrandPrice snapshotRetailerDimensionsWeightFrameGlazingDoorVentilationFloorAssemblyWarrantyRoof styleSizeGrowing featurePlacement
Mercia Traditional Greenhouse 4x6Mercia£479.99One Garden192.8 × 124.1 × 206 cm94 kgDip-treated shiplap timberStyreneHinged single door1 windowNot suppliedSelf-assemblyConditional 10-year anti-rot, annual retreatment required————
Mercia Traditional Greenhouse 6x6Mercia£779.99One Garden192.8 × 182.4 × 206 cm111 kgDip-treated shiplap timberStyreneHinged single door1 opening roof ventNot suppliedSelf-assembly, 2 people, 4 to 6 hoursConditional 10-year anti-rot, annual retreatment required————
Mercia Traditional Greenhouse 8x6Mercia£679.99One Garden192.8 × 240.7 × 206 cm128 kgDip-treated shiplap timberStyreneHinged single door1 opening roof ventNot suppliedSelf-assembly, 2 people, 4 to 6 hoursConditional 10-year anti-rot, annual retreatment required————
Evesham Wooden Greenhouse 6 x 4Waltons£559.99WaltonsApprox. 183 × 122 cm nominal footprint (6 × 4 ft) cm—TimberUV-resistant shatterproof styrene—Opening roof ventNot supplied——Apex6 × 4 ft variant——
Evesham Victorian Growhouse 6 x 3Waltons£559.99WaltonsApprox. 183 × 91 cm nominal footprint (6 × 3 ft) cm—TimberStyrene——————6 × 3 ftInternal potting shelves—
Evesham Lean-to Pent Wooden Greenhouse 8 x 4Waltons£519.99WaltonsApprox. 244 × 122 cm nominal footprint (8 × 4 ft) cm—TimberStyrene—————Pent lean-to8 × 4 ft—Designed to attach to a permanent wall

The details

Six styrene-glazed greenhouses compared

Product photo of Mercia Traditional Greenhouse 4x6

01 · Best Entry-Level Mercia

Mercia Traditional Greenhouse 4x6

The cheapest Mercia here at £479.99, with a window and hinged door, though it has the smallest footprint of the three.

The Mercia Traditional Greenhouse 4x6 is the entry point to the Mercia range in this group. It measures 192.8 x 124.1 x 206 cm, with dip-treated shiplap timber and styrene glazing. Ventilation comes from a single window, and there is a hinged single door. At 94 kg it is the lightest of the three Mercia models. No floor is supplied, so you would need to plan the base. The 10-year anti-rot warranty is conditional on annual retreatment. It is a sensible choice if you want the Mercia look without paying for extra length.

Price snapshot: £479.99 at One Garden, recorded 2026-11-02. Check the retailer page for the current price.

Key specifications

Dimensions
192.8 × 124.1 × 206 cm
Weight
94 kg
Frame
Dip-treated shiplap timber
Glazing
Styrene
Door
Hinged single door
Ventilation
1 window
Floor
Not supplied
Assembly
Self-assembly
Warranty
Conditional 10-year anti-rot, annual retreatment required

What stands out

  • Lowest price of the Mercia models at £479.99
  • Lightest Mercia at 94 kg, with a hinged single door and a window

Things to consider

  • Ventilation is a single window rather than a roof vent
  • Anti-rot warranty is conditional on annual retreatment
View One Garden
Product photo of Mercia Traditional Greenhouse 6x6

02 · Best Mercia for Roof Ventilation on a Mid-Size Footprint

Mercia Traditional Greenhouse 6x6

A mid-size Mercia with an opening roof vent, but it costs £100 more than the larger 8x6.

The Mercia Traditional Greenhouse 6x6 is wider than the 4x6, at 182.4 cm deep, and adds an opening roof vent for airflow. It stands 206 cm tall, uses dip-treated shiplap timber with styrene glazing, and weighs 111 kg. The hinged single door matches the other Mercia models, and no floor is supplied. Assembly is listed as a two-person job taking around 4 to 6 hours. The 10-year anti-rot warranty is conditional on annual retreatment. The sticking point is price, as £779.99 is the highest in this group and £100 more than the bigger 8x6.

Price snapshot: £779.99 at One Garden, recorded 2026-11-02. Check the retailer page for the current price.

Key specifications

Dimensions
192.8 × 182.4 × 206 cm
Weight
111 kg
Frame
Dip-treated shiplap timber
Glazing
Styrene
Door
Hinged single door
Ventilation
1 opening roof vent
Floor
Not supplied
Assembly
Self-assembly, 2 people, 4 to 6 hours
Warranty
Conditional 10-year anti-rot, annual retreatment required

What stands out

  • Opening roof vent for ventilation
  • Deeper 182.4 cm footprint than the 4x6, with the same 206 cm height

Things to consider

  • Priciest greenhouse here at £779.99, £100 more than the larger 8x6
  • Anti-rot warranty is conditional on annual retreatment
View One Garden
Product photo of Mercia Traditional Greenhouse 8x6

03 · Best Value Large Greenhouse

Mercia Traditional Greenhouse 8x6

The largest greenhouse here and cheaper than the 6x6, with an opening roof vent and hinged door.

The Mercia Traditional Greenhouse 8x6 gives the most floor space of the six, at 192.8 x 240.7 cm, and still stands 206 cm tall. Dip-treated shiplap timber and styrene glazing are used, with an opening roof vent and a hinged single door. At 128 kg it is the heaviest option, and assembly is listed as taking two people around 4 to 6 hours. Costing £679.99, it undercuts the smaller 6x6 by £100, which makes it good value on the numbers. No floor is supplied, and the 10-year anti-rot warranty needs annual retreatment.

Price snapshot: £679.99 at One Garden, recorded 2026-11-02. Check the retailer page for the current price.

Key specifications

Dimensions
192.8 × 240.7 × 206 cm
Weight
128 kg
Frame
Dip-treated shiplap timber
Glazing
Styrene
Door
Hinged single door
Ventilation
1 opening roof vent
Floor
Not supplied
Assembly
Self-assembly, 2 people, 4 to 6 hours
Warranty
Conditional 10-year anti-rot, annual retreatment required

What stands out

  • Largest footprint in the group at 192.8 x 240.7 cm
  • £679.99 is £100 less than the smaller Mercia 6x6

Things to consider

  • Heaviest model at 128 kg, so assembly is a two-person job of around 4 to 6 hours
  • Conditional anti-rot warranty requires annual retreatment
View One Garden
Product photo of Evesham Wooden Greenhouse 6 x 4

04 · Best UK-Made Timber Option

Evesham Wooden Greenhouse 6 x 4

A classic apex greenhouse with a roof vent and an unconditional-sounding 10-year anti-rot guarantee, for £559.99.

The Evesham Wooden Greenhouse 6 x 4 is a traditional shiplap greenhouse with an apex roof, an opening roof vent and UV-resistant shatterproof styrene glazing. The retailer describes UK-made PEFC timber construction and a 10-year anti-rot guarantee. Its floorless drainage design means no floor is supplied. At about 183 x 122 cm, it suits a compact space, and it is self-assembly. At £559.99 it costs £80 more than the Mercia 4x6, so it is a choice for those who value the UK-made timber and the roof vent.

Price snapshot: £559.99 at Waltons, recorded 2026-11-03. Check the retailer page for the current price.

Key specifications

Frame
Timber
Glazing
UV-resistant shatterproof styrene
Roof style
Apex
Ventilation
Opening roof vent
Floor
Not supplied
Size
6 × 4 ft variant
Dimensions
Approx. 183 × 122 cm nominal footprint (6 × 4 ft) cm

What stands out

  • UK-made PEFC timber construction with a 10-year anti-rot guarantee
  • Opening roof vent and UV-resistant shatterproof styrene glazing

Things to consider

  • £559.99 is £80 more than the Mercia 4x6
  • Floorless design means no floor is supplied
View Waltons
Product photo of Evesham Victorian Growhouse 6 x 3

05 · Best Compact Growhouse

Evesham Victorian Growhouse 6 x 3

A small 6 x 3 ft growhouse with internal potting shelves, though it costs as much as the larger Evesham 6 x 4.

The Evesham Victorian Growhouse 6 x 3 is the smallest greenhouse here, with a nominal footprint of about 183 x 91 cm. The timber frame is glazed with styrene, and the standout feature is the set of internal potting shelves. The retailer positions it for smaller gardens and for growing seedlings or produce. It is self-assembly and carries a 10-year anti-rot guarantee. At £559.99 it matches the price of the bigger Evesham 6 x 4, so you are paying for the shelving and compact shape rather than extra space.

Price snapshot: £559.99 at Waltons, recorded 2026-11-03. Check the retailer page for the current price.

Key specifications

Frame
Timber
Glazing
Styrene
Growing feature
Internal potting shelves
Size
6 × 3 ft
Dimensions
Approx. 183 × 91 cm nominal footprint (6 × 3 ft) cm

What stands out

  • Internal potting shelves built in
  • Compact 6 x 3 ft footprint suits smaller gardens

Things to consider

  • £559.99 is the same price as the larger Evesham 6 x 4
  • Smallest footprint in the group at about 183 x 91 cm
View Waltons
Product photo of Evesham Lean-to Pent Wooden Greenhouse 8 x 4

06 · Best Lean-to for Walls

Evesham Lean-to Pent Wooden Greenhouse 8 x 4

A space-saving pent greenhouse designed to sit against a permanent wall, and the cheapest Waltons model here at £519.99.

The Evesham Lean-to Pent Wooden Greenhouse 8 x 4 is built to attach to a permanent wall, which makes it a fit for smaller and urban gardens, as the retailer describes. It has a pent roof, a timber frame and styrene glazing, with a nominal footprint of about 244 x 122 cm. That gives more length than the 6 x 4 Evesham for £40 less, at £519.99. It is self-assembly and covered by a 10-year anti-rot guarantee. Because it is designed to sit against a wall, it needs a suitable permanent wall, so it will not suit an open spot in the middle of a garden.

Price snapshot: £519.99 at Waltons, recorded 2026-11-03. Check the retailer page for the current price.

Key specifications

Frame
Timber
Glazing
Styrene
Roof style
Pent lean-to
Placement
Designed to attach to a permanent wall
Size
8 × 4 ft
Dimensions
Approx. 244 × 122 cm nominal footprint (8 × 4 ft) cm

What stands out

  • Designed to attach to a permanent wall, saving garden space
  • £519.99 is £40 less than the Evesham 6 x 4, with a longer 8 ft run

Things to consider

  • Needs a permanent wall to attach to, so placement is limited
View Waltons