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Mercia Premium Pent Greenhouse 8x4

Product Code: ONE3006

Detailed Measurements


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Usually £619.99 Saving £35.00


inc VAT & FREE delivery*

In Stock

Pick-A-Day home delivery from Monday 29th July (subject to location)

Free delivery? Check now


  • Classic lean-to wooden greenhouse for adjacent wall placement
  • Door can be positioned at either end on assembly
  • Basecoat treated at the factory
  • Safety styrene-glazed windows, one opens as a roof vent
  • Quality key lock for security
  • Full instructions and fixings provided

Home delivery 7-14 days (estimate)

Check your location for the Mercia delivery service and cost: *A distant location may attract a delivery surcharge

Recommended Options and Accessories

Mercia Premium Pent Greenhouse 8x4



Added Optional Extras: - no extras selected

Total Price: £584.99
inc VAT & FREE delivery*


Detailed Measurements

Extreme Width (max) 1357mm  -  4' 5"
Extreme Depth (max) 2492mm  -  8' 2"
Extreme Height (max) 2093mm  -  6' 10"
Footprint/ground Width 1312mm  -  4' 4"
Footprint/ground Depth 2492mm  -  8' 2"
Ridge Height 2070mm  -  6' 9"
Eaves Height 1812mm  -  5' 11"
Door Height 1715mm  -  5' 8"
Door Width 600mm  -  2' 0"
Framing Width 44mm  -  0' 2"
Framing Depth 28mm  -  0' 1"

Note: All imperial sizes stated are approximate, rounded to the nearest inch.


Material Wood
Cladding Tongue & groove
Finish Planed
Colour Brown
Treatment Dip-treated
Door Position In gable end
Orientation 1.357m Gables / 2.492m front (max)
Door Type Hinged single
Door Catch Key lock
Roof Type Pent
Wall Material 12mm Tongue & groove
Cladding Material Tongue & groove
Floor Material No floor
Fixed Windows Many
Opening Windows 1
Glazing Material Styrene
Sustainable Timber Yes
Made in Britain Yes

Assembly & Care

Installation Self-assembly by customer
Persons to Assemble (min) 2
Estimated Assembly Time 2 to 4 Hours
Parts Fit Through Door (78x30") Yes
Interchangeable Sides Yes
Annual Treatment Yes by customer

Useful To Know

Warranty 10 Year Anti-rot
Recommended Use Planting & cultivation
Includes Full instructions and fixings
Excludes A floor, ground-based fixings & assembly

Our product specifications are given in good faith but can be subject to manufacturer change without notice. Should an attribute be of essense to your purchase, please feel free to contact us first for confirmation.


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Made in the UK
One Garden is proud to support UK-based manufacturing. Products with this mark are directly sourced from official manufacturers in the UK.

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10 Year Anti-Rot Warranty
An assurance from the manufacturer that their timber product, if maintained according to their policy, will resist rot within a 10 year period.

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Sustainably Sourced Timber
The timber used for this product was obtained from a managed resource, where responsible forest management and re-planting are employed.

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Dipped Treatment
The process where a timber component is exposed to a preservative by immersion in an open tank or by deluge spray booth.

glazing-styrene image

Styrene, Polycarbonate and Acrylic are all terms for tough, single sheet plastic glazing. Styrene will not shatter like glass, so it is ideal for playhouses.

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Key Lock
A common door locking system, which can only opened with the key provided. The design and finish can vary by product.


This freestanding lean-to style wooden greenhouse has been designed to be built against a wall or other such structure. There is no floor, so, the surface that you install the greenhouse onto will become the flooring inside. 

The framework is a strong 44x28mm and the building comes part clad with 12mm tongue and groove to the lower sections of the walls.

Glazed with styrene, which is designed not to shatter if it gets broken. The roof has an opening vent to allow you to regulate the temperature inside the greenhouse.

A key lock on the single door is included as standard.



The Mercia Premium Pent Greenhouse 8x4 is delivered from central UK stocks held at our manufacturer. The manufacturer's own experienced personnel undertake delivery with careful handling to ensure the goods arrive in a perfect condition.


This manufacturer operates mostly 3.5 ton small flat-bed trucks. These will reach most locations an average car can. On occasion, a larger 7.5 ton lorry may be necessary.


Unloading will take place at the kerb-side or onto your adjacent driveway. Vehicles will not leave the public highway. A driver may be willing to carry the goods into your garden at their own discretion. Goods cannot be carried through your home, therefore if necessary please arrange some extra help privately.

Free Delivery

This manufacturer offers free delivery* within central, mainland England only. The above postcode checker will confirm this for you.

Delivery Period

Delivery will typically be made within the period quoted on this product. The manufacturer will notify you in advance by either telephone, text or email to confirm the date of delivery. On the morning of delivery, an email or text will be sent by the manufacturer to advise you of an estimated '2 hour delivery time slot'. Where possible, the driver may also call to update you on their progress. 

Pick A Day Delivery

Should your location qualify, during the checkout process you will be offered a real time calendar which will allow you to select a preferred delivery date. The manufacturer will endeavour to deliver on the date you have chosen. You will be promptly notified in the rare event that an alternative date is necessary for logistical reasons.

Orders with Optional Installation

The delivery of your goods will happen independently (as if for a self-assembly order) and prior to installation. Typically, the manufacturer's installation team will be scheduled to visit your address 2-3 days after delivery. You will be advised of the installation date by telephone. Note: Due to additional labour scheduling, an installation service option may add approximately 3 weeks to the overall delivery period. 

Extended Delivery

Less frequently serviced locations may be subject to an extended delivery period of up to an additional 14 days. These distant locations include; Scottish Highlands (AB, IV, KW, PA & PH).

Offshore Delivery

Offshore locations are not serviced for this product. We cannot deliver to; (BT) Northern Ireland, Guernsey (GY), Western Isles (HS), Isle of Man (IM), Isle of Wight (PO30-41), Isles of Scilly (TR21-25), Jersey (JE) and Shetlands (ZE). Other Scottish islands, for example those under selected IV, KA, KW, PA & PH post codes, also cannot be serviced.

Distant Surcharge

Due to additional zone fees, certain distant locations can only be serviced at a surcharge (at cost). The above post code checker can confirm if a surcharge will apply.

These locations include:


ZONE 2 (AB,PA,PH,TR) = £89.99

ZONE 3 (IV,KW) = £119.99

Small Drop Fencing Orders (of less than 3 panels and/or gates) -  ! NOTE: The small drop service is presently unavailable, sorry.

To maintain a free delivery service for Guardian-branded fencing products, you must place at least 3 fence panels or gates (can be mixed) in your basket to proceed; 1 gate and 2 panels for example. Orders of a lesser quantity will automatically incur a small drop delivery charge of £15.00, supported by a warning notice on the basket page.

Notes & Information

Image Notes

The 8x4 model is shown, illustrating that the door can be positioned at either gable. The imagery may show products which have been dressed for photography purposes.

One Tip

For extra protection, we recommend that you apply a further preservative treatment within 3 months.

Price Watch

We work tirelessly to ensure that our extensive product range is competitively priced through regular monitoring. In the rare event that you find the Mercia Premium Pent Greenhouse 8x4 from another online retailer at a lower price then please let us know, we'll do our best to match or even beat it!

Simply submit your Price Watch enquiry using the form below, being sure to complete all fields. On receipt, we will verify that the competitors' offer is available to purchase, like-for-like and delivery inclusive.

Within 1 working day we will confirm One Garden's keenest offer to you, whether that's to beat, match or even congratulate our competitor. Go on, challenge us...

Brand Information

Mercia image

At Mercia Garden Products, we have been championing the Great British shed for over 140 years. In this time we have learned a thing or two about designing, manufacturing and delivering high quality timber garden products.

We understand that a garden building is not just functional but will also become a central feature to your garden. So much so, today, we manufacture and deliver over 100,000 wooden buildings every single year.

Our pride, passion and craftsmanship has elevated us to be one of the industry's leading, largest and longest running manufacturers creating perfect garden buildings, for every garden and budget.

Reviews (3)

  • 5 out of 5   , West Midlands .

    Tuesday 12th September 2023 Verified Purchase

    Great product good value for money and looks great in my garden

  • 4 out of 5   , Essex .

    Thursday 10th August 2023 Verified Purchase

    Excellent overall had some damage when it was delivered a crack in one of the windows which I had to replace and some of the panels had misplaced nails which needed repositioning.

  • 4 out of 5   , Thirsk.

    Sunday 26th June 2022 Verified Purchase

    Lovely, very robust lean too greenhouse, plenty of fixings enclosed in the kit. Does require a certain amount of joinery skill to ensure the building is built up level & secure as holes are not predrilled. Definitely requires two people to build it as stated in the instructions. Delivery was very efficient & exactly to requirements with a friendly service. Overall I am very pleased with the greenhouse as it should last for many years to come.

Click here to read all 3 reviews.

We encourage every purchaser of this product to submit a review. Customers are invited (by post-delivery email) to a web page where their genuine review can be placed.


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Can't find what you're looking for? ... Just give us a call (9am to 4pm weekdays) and we'll try to help you find the ideal model or suggest an alternative from our Wooden Greenhouses range.

Want to see more Wooden Greenhouses? ... Take a look at our full Wooden Greenhouses range for the widest possible choice.

Yes, free delivery!

At One Garden, we offer a free* home delivery service across the UK mainland on the vast majority of our products.

Some exceptions exist though for selected distant, offshore and less frequently serviced areas. Where applicable, a distant charge (at cost) will be shown before you buy. For peace of mind, every product page includes our postcode checker, allowing you to check if a surcharge applies to your location; on that product.

For more information about delivery, please take a look at our delivery and returns page.

If you buy more, you may save more!

We work closely with our factory partners to enable us to offer highly competitive retail pricing. If the factory price goes down, we pass on the savings by lowering our retail pricing too.

We love to reward extra custom, so look out for those products displaying a "Multi Buy Discounts" table. This'll offer a reduced unit price when a greater quantity is purchased. So, increase the 'Product Quantity', hit a trigger level and watch the price per item fall!

Being the loyal bunch we are, we enjoy rewarding loyalty shown by others too. Once fulfilled, we reward every order with a unique loyalty voucher, entitling a one-time 3% discount off a future purchase (redeemable within 6 months).

Our special offers and promotional discounts only appear online for a limited time, so don't delay, if a deal takes your fancy today... Buy now!

A range designed to fulfil your gardening needs and aspirations

One Garden offers an ever-growing range and variety of quality garden products, from a host of leading manufacturers. All delivered fresh from the factory, directly to your door.

From a traditional wooden shed like Grandpa used to have, through sleek metal sheds to the more contemporary plastic sheds, we are confident there'll be something here for you.

But... there's so much more to One Garden. We also offer an extensive range of fence panels and gates, garden structures and seating, storage, garages, log cabins, summerhouses, arbours, greenhouses, playhouses, decking, tools... the list goes on and on.

Our range is ever-expanding. We are always on the lookout for new gardening opportunities so why not bookmark this site, come back later and see what's new.

We care about your order as much as you do

One Garden provides a safe and secure environment for its customers. We want you to feel happy and confident with your decision to favour your order with us. Our checkout payment system conforms to the industry's toughest standards for example, being securely integrated with one of the World's largest payment processors.

Every order placed is supported by a series of email communications. From a transaction confirmation on placement, followed by our official VAT sales invoice (order confirmation) upon processing. You'll also receive delivery information, review reminder and loyalty voucher emails along the journey too.

For your peace of mind, we offer a 14 day no-quibble returns policy and a minimum 12 month parts warranty. Look out for each manufacturers' own warranty too.

One Garden is a debt-free, wholly UK-based Company. Our knowledgeable team have between 10 to 40+ years industry experience. We're here to offer any help or advice you may need.


All prices include VAT. Product names and filters show generic imperial sizes to aid comparison only. For actual size, see 'Detailed Measurements'.
Distant regions may attract a delivery surcharge; by location, brand or product. The product page 'Delivery' tab or postcode checker will confirm if a surcharge applies.