Grand proportions
An 11' 1" ridge and up to 224 sq ft of floor space give you room for tall plants and long benches.


The Alton Westminster is a durable, beautifully crafted greenhouse built with the same trusted construction as the Alton Evolution range. Designed to eliminate common rot points, it is guaranteed not to rot for 10 years. With treatment every 3 years, it could last 30–50 years.






Exaco · Hobby Greenhouse
Why customers choose it
An 11' 1" ridge and up to 224 sq ft of floor space give you room for tall plants and long benches.
Grade 1 Canadian cedar is dipped and sealed, and the common rot points have been designed out.
Up to 6 roof windows open on their own, and louvered windows add side ventilation.
Knee brace spandrels at every rafter and extra trusses in longer units keep the frame strong.
Large single panes of 3 mm toughened safety glass look neater and are easier to clean.
Slatted shelving, gutters and downpipes come standard.
The details
| Floor area | 180.56 sq ft (16' 8"), 202 sq ft (18' 9") or 224 sq ft (20' 10") |
|---|---|
| Exterior size | 10' 9" W x 16' 8", 18' 9" or 20' 10" L x 11' 1" H |
| Walking height | 5' 7" at the eaves, 11' 1" at the ridge |
| Frame | Grade 1 Western Red Cedar, knot-free, dipped and sealed |
|---|---|
| Glazing bars | 44 x 44 mm timbers, 44 x 69 mm in places |
| Glazing | 3 mm toughened safety glass, large single panes |
| Joinery | Mortise-and-tenon and tongue-and-groove, stainless steel hardware |
| Base | Aluminum base frame |
| Gutters | Gutters and downpipes on both sides |
| Made in | UK |
| Door | 2' 5" W x 6' 7" H single hinged door with lock |
|---|---|
| Roof windows | 4, 5 or 6 by size, with automatic openers |
| Louvered windows | 3 (16' 8") or 4 (18' 9" and 20' 10") |
| Rot guarantee | 10 years |
|---|---|
| Warranty | 10 year limited |
Plan, build and permit
Every manual, drawing and certificate is hosted on our own servers, so the links always work. Open on any device or save a copy for your builder or permit office.
Free curbside freight delivery
Choose your size, color and options. Your greenhouse ships from the manufacturer's warehouse, packed for freight.
We'll contact you to set up a delivery time frame that works for you.
Delivery is by LTL motor freight on an 18-wheeler. Let us know about tight roads or low wires so we can plan ahead.
Someone needs to be there to receive the delivery. The driver does most of the work but may need a hand.
Foundations and bases are bulky, so we recommend ordering them together with your greenhouse to avoid a separate freight charge.
Good to know
Can't find your answer? Our greenhouse specialists are happy to help you choose.
678-408-8222 Email usYes. Shipping is free. Locations with limited access, such as islands, are rare exceptions that may carry an extra fee, and we'll tell you before anything ships.
Yes. If you find the same greenhouse for less from an authorized dealer, call or email us with the offer and we'll review it.
Yes. Mulberry Greenhouses is an authorized retailer, so your greenhouse is covered by the full manufacturer warranty.