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Free delivery
on selected postcodes
0% interest finance
50 years experience
Manufactured in Great Britain
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20 x 12 Summerhouses

Would you like to maximise the use of your garden? Then why not create the perfect outdoor space to enjoy in any weather with our 20 x 12 summer houses? From extra seating to a creative space, whatever you wish to use them for, these quality built wooden summer houses are the perfect addition to any garden and built with such care and attention that they’ll withstand the elements for years to come.

With a minimum of 10 years anti-rot guarantee, these summer houses really are not only a fantastic investment, but a great way to extend your living space. With 0% finance and free delivery on selected postcodes, they’ve never been more affordable. For more information on our quality 20 x 12 summer houses, simply contact our friendly team of staff today.

Showing all 13 results

  • 20ft x 10ft diplomat long window grandmaster summerhouse shed

    Diplomat Grandmaster Long Window Summerhouse

    From £38.69 12.9% per month
    Total£1,393
    Sizes
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 10 to 24 x 12
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Alpine Grandmaster Long Window Summerhouse

    Alpine Grandmaster Long Window Summerhouse Cabin

    From £53.19 12.9% per month
    Total£1,915
    Sizes
    16 x 9
    20 x 9
    16 x 12
    20 x 12
    16 x 14
    20 x 14
    16 x 16
    20 x 16
    Show More Sizes
    Free delivery from Friday 28 September*
    From 16 x 9 to 20 x 16
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Diplomat Offset Grandmaster Summerhouse

    Diplomat Offset Grandmaster Summerhouse

    From £52.92 12.9% per month
    Total£1,905
    Sizes
    8 x 8
    10 x 8
    12 x 8
    14 x 8
    16 x 8
    18 x 8
    20 x 8
    22 x 8
    24 x 8
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    10 x 14
    12 x 14
    14 x 14
    16 x 14
    18 x 14
    20 x 14
    22 x 14
    24 x 14
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 24 x 14
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Diplomat Grandmaster Summerhouse

    Diplomat Grandmaster Summerhouse

    From £52.64 12.9% per month
    Total£1,895
    Sizes
    8 x 8
    10 x 8
    12 x 8
    14 x 8
    16 x 8
    18 x 8
    20 x 8
    22 x 8
    24 x 8
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    8 x 14
    10 x 14
    12 x 14
    14 x 14
    16 x 14
    18 x 14
    20 x 14
    22 x 14
    24 x 14
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 24 x 14
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Alpine Grandmaster Summerhouse

    Alpine Grandmaster Summerhouse Cabin

    From £59.17 12.9% per month
    Total£2,130
    Sizes
    16 x 9
    20 x 9
    16 x 12
    20 x 12
    16 x 14
    20 x 14
    16 x 16
    20 x 16
    Show More Sizes
    Free delivery from Friday 28 September*
    From 16 x 9 to 20 x 16
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Diplomat Grandmaster Summerhouse With Dorma

    Diplomat Grandmaster Summerhouse With Dorma

    From £82.22 12.9% per month
    Total£2,960
    Sizes
    8 x 8
    10 x 8
    12 x 8
    14 x 8
    16 x 8
    18 x 8
    20 x 8
    22 x 8
    24 x 8
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    8 x 14
    10 x 14
    12 x 14
    14 x 14
    16 x 14
    18 x 14
    20 x 14
    22 x 14
    24 x 14
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 24 x 14
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Grandmaster Duke Summerhouse TG Roof and Floor

    Duke Grandmaster Summerhouse

    From £52.19 12.9% per month
    Total£1,879
    Sizes
    8 x 8
    10 x 8
    12 x 8
    16 x 8
    20 x 8
    8 x 10
    10 x 10
    12 x 10
    16 x 10
    20 x 10
    12 x 12
    16 x 12
    20 x 12
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 20 x 12
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Pressure Treated Diplomat Offset Grandmaster Summerhouse

    Pressure Treated Diplomat Offset Grandmaster Summerhouse

    From £33.61 12.9% per month
    Total£1,210
    Sizes
    8 x 8
    10 x 8
    12 x 8
    14 x 8
    16 x 8
    18 x 8
    20 x 8
    22 x 8
    24 x 8
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    10 x 14
    12 x 14
    14 x 14
    16 x 14
    18 x 14
    20 x 14
    22 x 14
    24 x 14
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 24 x 14
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    15 year anti rot guarantee
    Fully opening windows
    View Product
  • Pressure Treated Alpine Grandmaster Summerhouse

    Pressure Treated Alpine Grandmaster Summerhouse Cabin

    From £87.78 12.9% per month
    Total£3,160
    Sizes
    16 x 9
    20 x 9
    16 x 12
    20 x 12
    16 x 14
    20 x 14
    16 x 16
    20 x 16
    Show More Sizes
    Free delivery from Friday 28 September*
    From 16 x 9 to 20 x 16
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    15 year anti rot guarantee
    Fully opening windows
    View Product
  • Pressure Treated Diplomat Grandmaster Summerhouse

    Pressure Treated Diplomat Grandmaster Summerhouse

    From £38.50 12.9% per month
    Total£1,386
    Sizes
    8 x 8
    10 x 8
    12 x 8
    14 x 8
    16 x 8
    18 x 8
    20 x 8
    22 x 8
    24 x 8
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    8 x 14
    10 x 14
    12 x 14
    14 x 14
    16 x 14
    18 x 14
    20 x 14
    22 x 14
    24 x 14
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 24 x 14
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    15 year anti rot guarantee
    Fully opening windows
    View Product
  • Pressure Treated Diplomat Grandmaster Summerhouse With Dorma

    Pressure Treated Diplomat Grandmaster Summerhouse With Dorma

    From £44.78 12.9% per month
    Total£1,612
    Sizes
    8 x 8
    10 x 8
    12 x 8
    14 x 8
    16 x 8
    18 x 8
    20 x 8
    22 x 8
    24 x 8
    8 x 10
    10 x 10
    12 x 10
    14 x 10
    16 x 10
    18 x 10
    20 x 10
    22 x 10
    24 x 10
    8 x 12
    10 x 12
    12 x 12
    14 x 12
    16 x 12
    18 x 12
    20 x 12
    22 x 12
    24 x 12
    8 x 14
    10 x 14
    12 x 14
    14 x 14
    16 x 14
    18 x 14
    20 x 14
    22 x 14
    24 x 14
    Show More Sizes
    Free delivery from Friday 28 September*
    From 8 x 8 to 24 x 14
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    View Product
  • Pressure Treated Duke Grandmaster Summerhouse

    Pressure Treated Duke Grandmaster Summerhouse

    From £44.69 12.9% per month
    Total£1,609
    Sizes
    10 x 8
    12 x 8
    16 x 8
    8 x 10
    10 x 10
    12 x 10
    16 x 10
    20 x 10
    12 x 12
    16 x 12
    20 x 12
    Show More Sizes
    Free delivery from Friday 28 September*
    From 10 x 8 to 20 x 12
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    15 year anti rot guarantee
    Fully opening windows
    View Product
  • diplomat-new day scene-a

    Diplomat Grandmaster Insulated Garden Room

    From £156.78 12.9% per month
    Total£5,644
    Sizes
    12 x 8
    16 x 8
    20 x 8
    12 x 10
    16 x 10
    20 x 10
    12 x 12
    16 x 12
    20 x 12
    Show More Sizes
    Free delivery from Friday 28 September*
    From 12 x 8 to 20 x 12
    Mortice lock and lockable windows
    Extra tall inside
    Stronger and taller double doors
    16mm cladding upgrade
    10 year anti rot guarantee
    Fully opening windows
    Fully insulated
    View Product
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