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INSTALATION AVAILABLE Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly
First Added - February 27 2022
Last Updated - August 4 2022 - 12 Data Points Updated - 3 Data Points Added
Reviewed & curated by a panel of garden building experts. Using methodology 1.1
Product ID: SKU: 178181
Size: 9' x 9'
Merchants Checked: 12
Available From: 1
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Our verdict on the Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly
The Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly comes with a pent style roof, fit with double doors, is treated using a dip treated process [1], and makes use of fsc® certified materials. The 2 windows used on this particular 9′ x 9′ use a styrene [2] glazing material (Thickness was not specified).
Base material: european softwood
Certifications this product meets:
FSC certified timber[3]
Our experts say this has 2 stand out features. A stand out feature is something found on over 70% of the top 10% of products in a particular category or is an exceptionally good feature as rated by our panel of experts.
1. When looking at cladding material used on the top 10% of all garden rooms, shiplap tongue & groove is used on 78% of them.
2. The mineral felt roof covering found on this garden room is rated to be one of the best by our experts.
Below is a brief overview of how some of the key points of this garden room fairs across the market.
Cladding
The shiplap tongue & groove cladding(walls) used here is one of the best forms of construction for garden room walls out of the 3 types [4] we’ve identified on same-size garden rooms, that you’ll also see getting used on 43% (41 of 95) of all garden rooms analysed [5], as well as being used on 78% (7 of 9) of the top 10% of garden rooms [6]. Even though the Expert Score of this particular garden room is 3 points below that of the average shiplap tongue & groove clad 9′ x 9’s (they have an average Expert Score of 85), with it being on 78% of the top 10%, its use here is a reassuring sign of a high quality cladding. You’ll also find the shiplap tongue & groove cladding showing up on 43% of 9′ x 9′ garden rooms (6 in total) [7].
The walls are 12mm thick and we rate this an about average thickness out of the 8 found on same-size garden rooms [8]. It is used on 44% of all garden rooms [9] and is also used across 44% of the top 10% of garden rooms [10] we analysed. Even though the Expert Score of this particular garden room is 1 point below the average 12mm clad 9′ x 9’s score of 83, the fact that 44% of the top 10% use a cladding this thick is reassuring as a sign of quality. 29% of 9′ x 9′ garden rooms (4 in total) use 12mm thick walls [11].
Read full analysis for cladding.
Roofing
Mineral felt is used as the roof covering, and out of 2 types identified on same-size garden rooms [12], is said to be one of the best roof covering materials. It comes fitted on 32% of garden rooms and used on 56% of the top 10% of 9′ x 9′ garden rooms. Even though the Expert Score of this particular garden room is below the average 9′ x 9’s cover their roofs with mineral felt (82 vs the average of 83), with it being on 56% of the top 10%, this should give you confidence in its quality. 36% of 9′ x 9′ garden rooms (5 in total) make use of a mineral felt material as a roof covering.
Read full analysis for roofing.
Window
Styrene windows come installed on this garden room. As a glazing option, we rate it the worst out of the 3 glazing types found on 9′ x 9′ garden rooms [13]. This particular type of glazing is used on 13% of all windowed garden rooms with a look at the top 10% of garden rooms showing us that none of them choose to install windows with this kind of glazing. 25% of 9′ x 9′ garden rooms with windows (3 in total) use styrene windows, and when taking the average Expert Score of those styrene 9′ x 9′ garden rooms (81), the Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly is just above the average with an Expert Score of 82.
Read full analysis for window.
Height
The height of this garden room is 2146.0mm (7′) which is 3% less than the average 9′ x 9′ garden room, giving you 56.0mm (0.2′) less headroom.
Read full analysis for height.
You Might Also Consider
We found 13 9′ x 9′ garden rooms with comparable specifications. The Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly has an Expert Score that is 2% lower than average and is £139 less expensive than average. If you are looking for the best value or highest expert scoring garden rooms out of the 13 with comparable specifications the following might be of interest.
Best value – If you are looking for something comparable that costs less, then you could save £1,661 with this Optional extra – Add top coat Shire 12′ x 7′ Double Door with Two Opening Windows Dip Treated Garden Studio Summerhouse Top Coat. It is priced at £239, this is 696% less than this and has an Expert Score of 87, 5 points higher than the Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly.
Highest Expert Score – With an Expert Score of 90 vs 82 for this product, the Redlands 12′ x 8′ Studio Summer House is the best 9′ x 9′ garden room with comparable specifications, and is priced at £4,734, that’s £2,834 more than the Mercia 9 x 9ft Large Double Door Corner Summer House with Assembly.
High Wind Area – If you live in a particularly exposed or high wind area then having a garden room with a thicker cladding and higher than average frame thickness can be preferable. We found at least 3 garden rooms that have a combination of features that can make them more suited to higher wind areas.
Redlands 12′ x 8′ Studio Summer House
Loxley 10′ x 10′ Oxhill Corner Summerhouse
Shire 12 x 7ft Double Glazed Timber Apex Garden Office
Coastal Consideration – If you live in a particularly wet or harsher environment such as by the coast then you might want to consider something with a more robust pressure treatment or something made from metal or plastic, both materials that are particularly suited to such harsh environments. We’ve found at least 2 garden rooms that have a combination of features that can make them more suited to higher wind areas.
Redlands 12′ x 8′ Studio Summer House
3m x 3m Insulated 64mm Pressure Treated Garden Office + Free Installation
Public-Facing – Extra security measures might be more of a concern if you’re placing your building in an area that is more public-facing than a garden. Features such as security windows or even having no windows at all, and the ability to lock all opening doors are usually much more important when you have something that is more public-facing. We found at least 3 garden rooms that have options that you might find a better fit if this is a concern you have.
Shire 10x8ft Highclere Double Door Summerhouse
Forest Xtend 2.5 Insulated Garden Office 2.54m x 2.9m
10 x 8 Shire Highclere Contemporary Summerhouse
More Child Friendly – If you have children and you are looking for something that has that little extra in terms of durability then tougher glazing options might be a better option. Here we have at least 3 other options that will fill those needs.
Redlands 12′ x 8′ Studio Summer House
Shire 12 x 7ft Double Glazed Timber Apex Garden Office
Loxley 10′ x 10′ Rowan Corner Summer House
Product Details
Comparisons of Similar Sheds
 |  |  |  |  | |
| Expert Score | 83 | 80 | 83 | 88 | 80 |
|---|---|---|---|---|---|
| Price | £2,329.00 | £8,199.00 | £1,074.00 | £13,306.51 | £3,095.99 |
| Size | 12' x 8' | 10' x 10' | 7' x 5' | 10' x 10' | 20'x8' |
| Brand | Shire | Forest Xtend | Loxley | Marlborough Insulated Buildings | Tiger Sheds |
| Material | Wooden | Wooden | Wooden | Wooden | Wooden |
| Cladding Thickness | 12mm | 12mm | 64mm | 12mm | |
| Guarantee | 10 Years | 15 Years | 10 Years | ||
| Go | Go | Go | Go | Go |
Similar Categories
Corner Summer HousesSmall Summer HousesWooden Summer Houses9x9 Summer HousesGarden OfficesCorner Garden RoomsSmall Corner Summer HousesCorner Garden OfficePent Summer Houses
Sources
Merchants Checked
12 different sources were used to research information on this product, and 1 contained information that we were able to use to compile the data used on this page.
The following merchants were checked on the 06 August, 2022 to see if they stocked this product.
Wickes – 19576 products checked, found 1 match.
Waltons – 231 products checked, found no matches.
B&Q – 78905 products checked, found no matches.
ManoMano UK – 922302 products checked, found no matches.
Wilko.com – 21232 products checked, found no matches.
Homebase – 35509 products checked, found no matches.
Buy Sheds Direct – 1635 products checked, found no matches.
sheds.co.uk – 1999 products checked, found no matches.
BillyOh – 1244 products checked, found no matches.
Garden Buildings Direct – 1284 products checked, found no matches.
Shedstore – 1373 products checked, found no matches.
Tiger Sheds – 635 products checked, found no matches.
1. Dip Treated: Dip treating is a temporary protective base coat treatment that is mainly designed to help protect the building during transit and for around one month after it is assembled. This water-based treatment is the least time-consuming and cheapest type of wood treatment. It involves dipping the wood in a protective water-based preservative and then leaving it to dry. The action of dipping is where ‘dip treatment’ comes from.
A dip-treated garden building is not considered fully treated with wood preservatives; it’s vital to re-treat your dip-treated building, preferably with a solvent-based (or oil-based) wood treatment. Then re-treat it on an annual basis using a solvent-based (or oil-based) wood treatment.
If you don’t want to treat something on an annual basis then a pressure treated wooden building might be a better option, this is where the wood undergoes a process called tanalisation (pressure treatment) during production. This is where the timber is submerged in specialist wood preservatives (such as Tanalith E, this is actually the origin of the word ‘tanalisation’), the wood then goes into a high pressure vacuum tank to draw out excess moisture and air and force in the preservatives. This deep penetration of the exterior wood protects it from the elements and all forms of insect attack. Wood treated this way can last many years without being re-treated. The Wood Protection Association has a good article/video on this. ↩
2. Styrene (Polystyrene (High Impact) HIPS): Styrene as it is commonly known or High Impact Polystyrene (HIPS) is a very versatile form of plastic. It has a very wide range of uses but for garden buildings styrene is typically used as a budget option for windows.
Styrene is a shatter-resistant material, which is why it is ideal for situations where safety needs to be considered, such as playhouses. This benefit can be offset by a few other drawbacks, unfortunately styrene has a tendency to yellow over time (the technical term is Photoyellowing and it is caused by prolonged exposure to UV Light), the degradation of its polymers over time also causes it to become more brittle.
Another drawback of styrene is its thermal coefficient of expansion (it is 80 x 10-6), this is higher than most other glazing options. This means that as the material heats up and cools it can contract and expand more than other glazing options. This cycle can lead to a loose fit of windows over time.
According to data from the British Plastics Fedaration the physical properties of Styrene (Polystyrene (High Impact) are that it is not very good when exposed to high heat with a maximum continuous use temperature of between 60 to 80 °C. This is coupled with the fairly low range the Notched Impact Strength data shows of 10.0 – 20.0 Kj/m². ↩
3. FSC Certified Timber: The Forest Stewardship Council (FSC) is an international organisation that is “dedicated to promoting responsible management of the world’s forests.” When you see the FSC certification it means the forest where this wood was sourced from is being managed in a way that preserves biological diversity, while ensuring it sustains economic viability. FSC-certified forests are managed to strict environmental, social and economic standards. FSC certified timber is comparable to Certified Timber. ↩
4. Cladding types identified: shiplap tongue & groove, timber, tongue & groove, wood ↩
5. Global cladding data sourced from: All shiplap tongue & groove garden rooms ↩
6. Top cladding data sourced from: Top 9 shiplap tongue & groove garden rooms ↩
7. 9′ x 9′ cladding data sourced from: 14 9′ x 9′ shiplap tongue & groove garden rooms ↩
9. Global cladding thickness data sourced from: All 12mm garden rooms ↩
10. Top cladding thickness data sourced from: Top 9 12mm garden rooms ↩
11. 9′ x 9′ cladding thickness data sourced from: 4 9′ x 9′ 12mm garden rooms ↩
12. Roof covering types identified: epdm synthetic rubber, mineral felt ↩
13. Glazing material types identified: double glazed, single glazed, styrene, toughened glass ↩