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    £20 OFF Greenhouses!

    Use code SPRING20 at checkout min order £599 (Greenhouses)

    Vitavia 8x12 Black Neptune 9900 Greenhouse

    Vitavia 8x12 Black Neptune 9900 Greenhouse - Toughened Glass
    FREE Delivery 4-6 Weeks ⛟
    SAVE £160
     Click to enlarge - For illustration purposes.

    Quick Code: P12473

    SAVE £20 EXTRA

    Pay ONLY £1245 TODAY!

    Use code SPRING20 at checkout
    • 8ft 5" wide x 12ft 6" deep
    • Black Powder Coated Frame
    • 3mm Toughened Glass
    • 2 x Roof Vents
    • Single Sliding Door
    • High Ridge Height
    • Built in Gutters
    • 12 Year Warranty
    • Easy to install
    Greenhouse Size Diagram

    Greenhouse Dimensions

    A: Greenhouse width

    2570mm (8′ 5″)

    B: Greenhouse depth

    3830mm (12′ 6″)

    C: Ridge height

    2300mm (7′ 6″)

    D: Eaves height

    1350mm (4′ 5″)

    E & F: Door Size

    610mm (2′) x 1860mm (6′ 1″) (aperture)

    Minimum Base Size

    2570mm (8′ 5″) x 3830mm (12′ 6″)

    Customise your Greenhouse

    More Sizes:

    Select your Glazing:

    Which glass do I need?

    Horticultural Glass

    This is standard greenhouse glass with 2' x 2' panes that overlap and join with S clips. This glass breaks into shards.

    Toughend Glass

    Recommended! Toughened Glass is much stronger than Horticultural glass and won't crack. If it does break it disintegrates into hundreds of small pieces.

    Polycarbonate Glazing

    Polycarbonate Glazing is ideal for family gardens where safety is the No 1 priority. It's virtually unbreakable and won't shatter.

    Select your Colour:

    Add a Base Plinth (Recommended):

    Add a galvanized steel base plinth for strength and stability.

    Do I need a Base Plinth?

    Vitavia Greenhouse Base Plinth

    Add a galvanized steel base plinth for strength and stability. Ideal for placing straight onto slabs or concrete. Includes corner posts for soft ground installations. Your greenhouse MUST sit on a raised plinth. You can build one from bricks, timber or easiest is to buy this base plinth with your new greenhouse.

    Save £32
    Vitavia Black Steel Base
    £123

    Get it installed by Professionals:

    Installation requires that you purchase the Base Plinth Option if one is available. You MUST have a surface of slabs, concrete or decking. NOT soil or gravel.

    Get it installed by Professionals?

    Installation

    Please Note: Installation requires an optional base plinth (if available) on a flat, level surface like slabs, concrete, or decking that meets the minimum base size. The package includes the greenhouse, ventilation, and downpipes only; accessories and groundwork are excluded. Installation will be carried out 2-8 weeks after the delivery of your Greenhouse.

    Installation is available in these postcode areas, if your area is not shown, please contact us directly.: B, BA, BB, BD, BL, BN, BS, CA, CB, CH, CO, CR, CT, CW, CV, DA, DE, DH, DL, DN, DY, EH, GL, GU, HD, HG, HP, HU, HX, IP, KA, KT, LA, LE, LL, LN, L, LS, M, ME, MK, ML, NE, NG, NN, NR, OX, OL, PE, PR, RG, RH, SE, SG, SK, SM, SN, ST, SW, SY, TF, TN, TS, TW, WA, WF, WN, WR, WS, WS, WV, YO.

    Installation
    £600

    Add Staging?

    £11 off
    1 Tier Staging Black
    + £74

    This 1 Tier Vitavia black greenhouse staging gives you a handy work surface and storage area. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    Qty 1
    £10 off
    1 Tier Staging Silver
    + £69

    This 1 Tier Vitavia silver greenhouse staging gives you a handy work surface and storage area. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    Qty 1
    £11 off
    2 Tier Staging Silver
    + £88

    This 2 Tier Vitavia silver greenhouse staging gives you a handy work surface with additional low level storage. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    Qty 1
    £6 off
    Top Tier Staging Extension Black
    + £39

    This little top level black shelf attaches to 1 or 2 Tier staging to give you a bit more storage space

    Qty 1
    £10 off
    Silver Shelf
    + £29

    Silver aluminium shelf that fixes to side of greenhouse. 122cm x 15cm

    Qty 1
    £23 off
    2 Tier Staging Black
    + £96

    This 2 Tier Vitavia black greenhouse staging gives you a handy work surface with additional low level storage. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    Qty 1
    £10 off
    Black Shelf
    + £49

    Black aluminium shelf that fixes to side of greenhouse. 122cm x 15cm

    Qty 1

    Staging information

    1 Tier Staging Black - £74.00
    1 Tier Staging Black

    This 1 Tier Vitavia black greenhouse staging gives you a handy work surface and storage area. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    1 Tier Staging Silver - £69.00
    1 Tier Staging Silver

    This 1 Tier Vitavia silver greenhouse staging gives you a handy work surface and storage area. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    2 Tier Staging Silver - £88.00
    2 Tier Staging Silver

    This 2 Tier Vitavia silver greenhouse staging gives you a handy work surface with additional low level storage. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    Top Tier Staging Extension Black - £39.00
    Top Tier Staging Extension Black

    This little top level black shelf attaches to 1 or 2 Tier staging to give you a bit more storage space

    Silver Aluminium Shelf - £29.00
    Silver Aluminium Shelf

    Silver aluminium shelf that fixes to side of greenhouse. 122cm x 15cm

    2 Tier Staging Black - £96.00
    2 Tier Staging Black

    This 2 Tier Vitavia black greenhouse staging gives you a handy work surface with additional low level storage. Dimensions: 76cm (H) x 50cm (D) x 120cm (W)

    Black Aluminium Shelf - £49.00
    Black Aluminium Shelf

    Black aluminium shelf that fixes to side of greenhouse. 122cm x 15cm

    Add Ventilation?

    £8 off
    Auto Roof Vent Opener
    + £38

    This automatic opener for your roof vents will automatically open your roof vents to ventilate your greenhouse when it becomes too hot.

    Qty 1
    £9 off
    Curtain Shading
    + £27

    Curtain shading will protect your plants from sun scorch and provide shade to moderate temperature. 6ft x 8ft.

    Qty 1
    £20 off
    Louvre Window Black
    + £45

    A louvre window brings fresh cool air into your greenhouse to moderate the temperature inside. An essential add on. Not available for Zeus models

    £1 off
    Auto Louvre Opener
    + £48

    This automatic opener mechanism will open your louvre window for you when you’re not around. No need to worry about ventilation, this does it automatically for you! (Does not include louvre window).

    Ventilation information

    Auto Roof Vent Opener - £38.00
    Auto Roof Vent Opener

    This automatic opener for your roof vents will automatically open your roof vents to ventilate your greenhouse when it becomes too hot.

    Curtain Shading - £27.00
    Curtain Shading

    Curtain shading will protect your plants from sun scorch and provide shade to moderate temperature. 6ft x 8ft.

    Louvre Window Black - £45.00
    Louvre Window Black

    A louvre window brings fresh cool air into your greenhouse to moderate the temperature inside. An essential add on. Not available for Zeus models

    Auto Louvre Opener - £48.00
    Auto Louvre Opener

    This automatic opener mechanism will open your louvre window for you when you’re not around. No need to worry about ventilation, this does it automatically for you! (Does not include louvre window).

    Add Extras?

    £9 off
    Rainwater Downpipe Kit
    + £16

    Kit contains 2 x Downpipes to collect the rainwater from the gutters in your greenhouse.

    £10 off
    Screwhooks
    + £7

    These handy screwhooks screw into the roof bars of your greenhouse for to attach wire or string to for growing vine plants like tomatoes. 10 screwhooks per pack.

    Qty 1
    £7 off
    Water Butt Connecting Kit
    + £17

    Hose and connector fittings to connect your Vitavia Downpipe to your Vitavia Water Butt.

    Qty 1

    Extras information

    Rainwater Downpipe Kit - £16.00
    Rainwater Downpipe Kit

    Kit contains 2 x Downpipes to collect the rainwater from the gutters in your greenhouse.

    Screwhooks - £7.00
    Screwhooks

    These handy screwhooks screw into the roof bars of your greenhouse for to attach wire or string to for growing vine plants like tomatoes. 10 screwhooks per pack.

    Water Butt Connecting Kit - £17.00
    Water Butt Connecting Kit

    Hose and connector fittings to connect your Vitavia Downpipe to your Vitavia Water Butt.

    Add Bar Capping?

    Glazing Bar Capping
    + £139

    Adding Bar Capping to your greenhouse makes the glazing fully secure in the frame. This is particularly advantageous with Polycarbonate that can flex in windy conditions.

    Bar Capping information

    Capping replaces the wire clips that hold your glass in the greenhouse frame.

    Glazing Bar Capping - £139.00
    Glazing Bar Capping

    Adding Bar Capping to your greenhouse makes the glazing fully secure in the frame. This is particularly advantageous with Polycarbonate that can flex in windy conditions.

    Add Black Cresting?

    Vitavia Black Roof Cresting
    + £115

    Complete the look of your Vitavia greenhouse with ridge crestings

    Black Cresting information

    Vitavia Black Roof Cresting - £115.00
    Vitavia Black Roof Cresting

    Complete the look of your Vitavia greenhouse with ridge crestings

    The 8x12 Vitavia Neptune 9900 Black Greenhouse is a superb 8ft wide large greenhouse at a great price !

    The Neptune Greenhouse is a spacious greenhouse for keen growers. An 8ft wide greenhouse gives those with a bit more space the ability to grow large crops in a very comfortable space big enough for all your growing needs.

    This Vitavia Neptune 8x12 has 2 opening roof vents for ventilation, a smooth sliding single door, powder coated Black finish and integral gutters.

    • 2570mm (8ft 5") Wide Aluminium Greenhouse - Practical width for serious growing.
    • Full Length 3mm Toughened Glazing - Great Safety and Wind Resistance.
    • 2 Opening Roof Vents - For good ventilation.
    • Black Powder Coated Aluminum Frame - No rust or discoloration!
    • Single Sliding Door - Door can be held at any desired position.
    • High Eaves (1350mm) - For Optimum Growing Height.
    • Integrated Gutters - Collect all that lovely rain water for your plants.
    • Extra Bracing and Corner Plates - for strength in roof and corners.
    • Optional 60mm Galvanised Steel Base Available Below - For rigidity and strength.
    • 12 Year Warranty - on frame and base.
    • PLEASE NOTE - Image shows 8x12 with Toughened Glass.

    Delivery is currently Within 4-6 Weeks to UK Mainland for Greenhouses, 3-5 Working days for Accessories only.

    Optional Installation: If selected, Installation will be carried out 1-8 weeks after the delivery of your Greenhouse. The Installation Team will contact you directly to book in your installation.Our installation service requires a level concrete, slabbed, or decked area to the minimum size stated on the website. Failure to provide a suitable base area may result in you being charged for the failed installation. If you require staging or shelving assembly, you can arrange it directly with the installation team.

    Greenhouse Size Diagram

    Greenhouse Dimensions

    A: Greenhouse width

    2570mm (8′ 5″)

    B: Greenhouse depth

    3830mm (12′ 6″)

    C: Ridge height

    2300mm (7′ 6″)

    D: Eaves height

    1350mm (4′ 5″)

    E & F: Door Size

    610mm (2′) x 1860mm (6′ 1″) (aperture)

    Minimum Base Size

    2570mm (8′ 5″) x 3830mm (12′ 6″)

    Toughened Safety Glass
    Toughened Safety Glass

    Our toughened safety glass offers superior clarity and durability. It's designed to break into small, less harmful pieces, providing enhanced safety for your greenhouse environment.

    Vitavia Powder Coated Green Frame
    Black Powder Coated Frame

    The Black powder coated frame and optional base look great and protect the aluminium from weathering. Powder coating is a process where powdered paint is applied using an electrostatic charge to transfer the powder to the aluminium.

    Vitavia Greenhouse
    Vitavia Greenhouses

    Vitavia Greenhouses are known for their high-quality construction, featuring corrosion-resistant aluminium frames and a range of glazing options. Designed for both novice and experienced gardeners, they offer durability, style, and excellent growing conditions.

    Vitavia Greenhouse 12 Year Warranty
    12 Year Warranty

    Vitavia greenhouses come with a 12-year warranty on the greenhouse frame. This warranty covers any manufacturing defects in materials or workmanship. However, it does not cover glass, polycarbonate or Wind Damage. The warranty is only valid if the greenhouse is assembled according to the provided instructions

    Frequently Asked Questions

    • Do I need a Vitavia Base Plinth?

      Yes, you'll definitely need some kind of base for your greenhouse. Here's why:

      1. The front door end of the frame sits a bit lower than the rest of the greenhouse.
      2. This means it needs to hang over something sturdy, like timber battens or a Vitavia Steel Perimeter base.
    • Why choose a Vitavia Steel Perimeter base?

      It's a great option because it:

      • Helps make sure your greenhouse is nice and square
      • Keeps everything level before you start adding the glass

      Think of it as giving your greenhouse a solid foundation to stand on. It's like making sure your house has good footings – it just makes everything more stable and secure. Remember, a well-set base means a happier, longer-lasting greenhouse!

    • How do I prepare the base for my greenhouse?

      For best results, build your greenhouse on a perfectly square and level slab or concrete base, or use anchor spikes if you have a Vitavia Base. You'll find the exact measurements and instructions for using the spikes in Section '0' of your assembly guide.

    • How is the Greenhouse Packaged?

      Your greenhouse frame and base will arrive in long, thin boxes made of sturdy cardboard. The glass packaging depends on what you've ordered: boxed for horticultural glass, or as individual sheets for full pane toughened glass.

    • Where do I find the assembly instructions?

      The assembly instructions will be in the main greenhouse box, and it will clearly state “assembly instructions in this box”. You can email us at sales@greenhousestores.co.uk and we can email them to you also.

    • How long does it take to build?

      Building your greenhouse is typically a weekend project: set aside Saturday for the framework and Sunday for glazing. Remember, it's crucial not to leave the greenhouse partially glazed, and the time may vary depending on the size of your greenhouse.

    • Where should I start with my greenhouse assembly?

      Begin by thoroughly reading the assembly instructions, then prepare the ground, assemble the base frame, build the greenhouse frame, and finish with glazing - in that order. Follow the instructions step-by-step, including the summary at the front of the manual, to ensure a smooth assembly process.

    • What if I'm missing parts or something is damaged?

      If you discover any missing or damaged parts, don't worry - we're here to help! Simply email us at support@greenhousestores.co.uk with your order number, and we'll get in touch with you as soon as possible to resolve the issue.

    • Do you provide installation services?

      If you're interested in this service, just add the Installation option above. One of our Professional Greenhouse Installers will install your new greenhouse for you. All we need is a properly prepared flat slab or concrete base to fit your greenhouse onto.

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