A 12ft wide polytunnel will easily allow you to have one central bed and a further growing bed on each side - a layout that can really maximise the use of space while making it easy for the gardener to get around. If you are taking the next step on your journey towards a more sustainable way of life then a 12ft polytunnel could be perfect - big enough to grow a quantity of food but not so big that it becomes overwhelming in a domestic setting, on an allotment or in a community garden.
Check out 'What's in the Kit' to find out exactly what is included in your purchase of a 12ft wide polytunnel, then scoot on over to our accessories sections to see what added extras you may wish to include. Crop bars and staging will help you make the most of your space, while you can optimise your tunnel to meet your particular needs with things such as base rails and sliding doors. Even better - the more extras you include, the more you can save with our fantastic bonus save offers. Just pop everything in your basket to find out how much you can save on your ideal 12ft wide polytunnel.
The 12ft (3.66m) wide Polytunnel is another very popular Domestic option, ideal for the larger garden or allotment. On this width the straight sides give you ample room for staging, increasing your growing potential no end. Like all of our Domestic models, it comes with 'real' doors at each end, ensuring good air circulation.
Technical Specification
| Width | 12ft (3.66m) |
|---|---|
| Hoop Spacing | 5ft (1.53m) |
| Overall Height | 7ft 7in (2.31m) |
| Straight Side | 3ft 3in (0.99m) |
| Head Room (15cm from side) | 4ft 8in (1.42m) |
| Hoop Diameter | 1in (25.4mm) (1½in (35mm) on Super) |
| Steel Specification | E370 Galv High Tensile |
| Door Opening Width | 2ft 3in (0.69m) |
| Door Opening Height | 6ft (1.83m) |
| Distance over Hoop | 22ft 8in (6.90m) |
| Door Frame | 3in x 2in (75mm x 47mm) |
| Inner Door | 2in x 2in (50mm x 50mm) |
| Base Rail | 3in x 2in (75mm x 47mm) |
Downloadable instructions before you buy. All of our Polytunnels are supplied with a printed copy of the assembly instructions, however we invite you to visit our dedicated construction portal at construct.firsttunels.co.uk prior to purchase. There you will find comprehensive instructions and videos available for download. This ensures that you are fully informed about the assembly process and what to expect from your Polytunnel.
Complete build videos. We’ve created a series of detailed videos, showcasing the entire construction process of our Polytunnels. From the basic setup to the inclusion of every possible option, these videos are designed to guide you through each step of the build. By watching these, you’ll gain a clear understanding of the effort and craftsmanship that goes into each of our Polytunnels.
Embark on the thrilling adventure of constructing your expansive 12ft wide polytunnel with our exclusive playlist! Immerse yourself in a thoughtfully crafted series of step-by-step tutorials, expert tips, and insightful demonstrations designed to guide you through each phase of your polytunnel project. From the initial planning stages to the final embellishments, think of us as your dedicated companion.
Discover the essential tools and materials crucial for a triumphant build, and uncover clever hacks tailored to simplify the process, ultimately saving you valuable time and effort. Our committed experts are ready to personally guide you through foundation preparation, frame assembly, cover installation, and all the intricate details needed for crafting a resilient and functional 12ft wide polytunnel.
Join us on this captivating journey to transform your gardening space into an impressive 12ft wide polytunnel haven. Happy gardening!
Click on a video below to watch on YouTube:
We supply Timber Hinged Doors at each end, Anti Hot Spot Tape, Timber Base Rails and of course the Framework to support our 200 micron Super Therm Polythene cover. These options are pre-selected below, but can be amended to suit your needs.
You will be required to secure the foundations into concrete, alternative methods of securing the polytunnel can be selected, eliminating the requirement of concrete – see ‘Polytunnel Foundation’ section.
Select the options below in order to configure your Polytunnel and when you’re happy, press "Add to basket"
Your first big decision when choosing a Polytunnel is almost always..."What size is ideal?". But there's other important factors to take into consideration..."What type of cover do I want?". It might not sound like something to give a lot of thought to, but the cover you choose will affect your day-to-day Polytunnel management, what and how you grow. We have 4 options to choose from...
Our most popular polythene cover incorporates an additive that increases its Thermic efficiency, yet still retains 90% light transmission. In simple terms the polythene helps trap and preserve higher temperatures inside the structures for much longer - in heated structures, a 15-20% fuel savings can be achieved. A beneficial side effect of this added additive is that light entering the polytunnel is diffused - scattering light evenly throughout the structure. This UV stabilised film is 200 microns (800 Gauge) and is supplied with a five year guarantee.
FOR USE WITH All crops where heat is important such as bedding/annual plants, propagation houses & over wintered vegetable production.
Our polythene is exclusively sourced from Sotrafa in Spain, the world's biggest producer of horticultural film with an enviable reputation for quality thanks to exhaustive testing in the demanding weather conditions of Almeria.
First Tunnels are the sole distributor of Sotrafa products in the UK, and we are proud to work with the global leader to deliver the best possible products for our customers. UK suppliers make cheaper alternatives, but the quality simply doesn't compare.
Although guaranteed for 7 years against its biggest threat of sunlight degradation, when fitted correctly, it is not uncommon to hear our polythene covers have lasted in excess of 10 years.
View the terms of the Guarantee here.
Sunlight is the biggest enemy of polythene. While it's essential for the wellbeing of whatever you're growing, it also 'kills' polythene in much the same way you can find old discarded crisp packets lose their colour and become very brittle. First Tunnels polythene covers are developed and tested in the extreme conditions to give optimum performance and are UV stabilised to prevent the polythene from breaking down prematurely.
What is a KLy?
A Kilo-Langley is the measure of Solar energy radiated in 1 year. It varies from a minimum of 60 KLy in the Polar regions to 120 KLy in warm regions, and to a maximum of 200 KLy in the African desert. Southern Spain receives about 140 KLy whereas the UK receives about half of that, just 78KLy.
Our Super Therm polythene is 800 gauge/200 micron and made up of 3 layers for outstanding strength and performance.
We use a 3 layer polythene made of exceptional quality material, which has a hugely beneficial thermal effect.
The common misconception about polythene is the more layers, the better the product. Unfortunately this isn't true. More layers simply hide poor quality films, which are sandwiched inside a very average inner and outer skin. The result of these multi-layer (often called 5 or 6 layer) films is a noticeably poorer all-round performance - the thermal effect is significantly decreased.
Total Transmission of Visible Light
The amount of available light entering the polytunnel through the film. Measured as a percentage of total light.
Super Therm = 95%
Diffusion
The scattering of direct light entering the polytunnel ensuring no shadows, so all plants receive equal light. Measured as a percentage of total light.
Super Therm = 30%
Thermal Effect
A pocket of additives within the layers of the film that ensure and maintain a stable and optimum temperature within the polytunnel, especially during the night when it is colder.
Super Therm = 85%
Strength at Break
The load on a tested sample when it breaks. This is expressed in Pascals or MPa.
Super Therm = MD24/TD23
Elongation at Break
The strain on a tested sample when it stretches. This is also expressed in Pascals or MPa.
Super Therm = MD920/TD920
Creep
As the weather changes becoming hotter or colder, so the Polythene expands and contracts. Creep is the terms used to express this.
Super Therm = 5
Dart Test
A test to measure the impact strength on a test piece of plastic, using a weighted falling 'dart'.
Super Therm = 450
This specialist film reduces light transmission to 65%, and ultimately the temperature inside the structure. This film is most useful where sun scorch is a problem for growers. It is also suitable for animal husbandry applications and other stock and storage houses where a great build up of heat is not ideal. This UV stabilised film is 180 microns (720 Gauge) and is supplied with a five year guarantee.
FOR USE WITH Animal Husbandry structures and those plants that would normally grow under a shade canopy.
bpi.visqueen is a division of British Polythene Industries plc - one of Europe's leading manufacturers of polythene film products. Their products are used by Farmers, vegetable, fruit and flower growers across the globe and are all designed to help the grower create their own 'climate for success'.
Although guaranteed for 5 years against its biggest threat of sunlight degradation, when fitted correctly, it is not uncommon to hear our polythene covers have lasted in excess of 10 years.
View the terms of the Guarantee here.
Sunlight is the biggest enemy of polythene. While it's essential for the wellbeing of whatever you're growing, it also 'kills' polythene in much the same way you can find old discarded crisp packets lose their colour and become very brittle. First Tunnels polythene covers are developed and tested in the extreme conditions to give optimum performance and are UV stabilised to prevent the polythene from breaking down prematurely.
What is a KLy?
A Kilo-Langley is the measure of Solar energy radiated in 1 year. It varies from a minimum of 60 KLy in the Polar regions to 120 KLy in warm regions, and to a maximum of 200 KLy in the African desert. Southern Spain receives about 140 KLy whereas the UK receives about half of that, just 78KLy.
Our Smart White polythene is 720 gauge/180 micron and made up of 3 layers for outstanding strength and performance.
Total Transmission of Visible Light
The amount of available light entering the polytunnel through the film. Measured as a percentage of total light.
Smart White = 65%
Diffusion
The scattering of direct light entering the polytunnel ensuring no shadows, so all plants receive equal light. Measured as a percentage of total light.
Smart White = N/A
Thermal Effect
A pocket of additives within the layers of the film that ensure and maintain a stable and optimum temperature within the polytunnel, especially during the night when it is colder.
Smart White = N/A
Strength at Break
The load on a tested sample when it breaks. This is expressed in Pascals or MPa.
Smart White = MD23/TD22
Elongation at Break
The strain on a tested sample when it stretches. This is also expressed in Pascals or MPa.
Smart White = MD630/TD770
Creep
As the weather changes becoming hotter or colder, so the Polythene expands and contracts. Creep is the terms used to express this.
Smart White = 5
Dart Test
A test to measure the impact strength on a test piece of plastic, using a weighted falling 'dart'.
Smart White = 700
This green net incorporates durable flat tape threads and double lockstitch tearproof technology and is used as a windbreak or shade product to protect those hardier and specialists plants. This net has proven its durability in the toughest of conditions and also provides excellent protection against insect and birds. 50% density.
Tildenet is now considered to be one of the major brands of netting and textile manufacturers in the world. Exporting to over 100 countries, providing an extensive range of products for markets such as construction, sport and horticulture. Tildernet supply and manufacture extruded nets and meshes for all kinds of applications.
We have five options available. Foundation Tubes can be driven into the ground (if the polythene is to be trenched) alternatively you can use Anchor Plates. The Screw Anchor can be used if ground conditions are suitable. If you have a solid base of concrete or timber then Base Plates will be required.
We have three options available. The Trench method requires a trench digging all around the perimeter of the tunnel approx. 30cm wide and no less than 40cm deep. Quicker and easier than trenching the cover, are Base Rails, which are available in Timber or Aluminium versions.
We have three options are available. The Super Upgrade option allows you to upgrade the polytunnel hoops to 35mm – ideal for those very exposed and windy sites. Crop Bars are attached to every hoop apart from the first and last. Twin Support Brace runs down the full length of the tunnel, either side of the central ridge, both are ideal for hanging baskets, suspending canes/nets & crops.
We have three options available. Side Ventilation is a fixed rail (Timber or Aluminium) underneath which, is fixed a net windbreak, allowing ventilation and air flow. In addition we also have Timber Side Ventilation & Screen, which allows the net to be covered through the use of a screen, which can be lowered/raised, helping control temperature and air flow. Please note, the Screen is not compatible with Aluminium. All options available, for one or both sides.
Ground Cover inhibits the growth of annoying weeds. Acting as an excellent sub-base for use with bark, mulch or gravel. Ground Cover provides total floor coverage, supplied with metal staples.
Staging introduces a work surface at the ideal height of 75cm, significantly adding growing space. Complete with brackets, allowing you to attach a worktop (not supplied) of your choice.
Polythene Care Kit contains 1 roll of 4 inch repair tape and a 2.5 litre container of Algon Organic.
Overhead Irrigation comprises a water pipe suspended below the central ridge. Supplied with a header pipe, down tubes, sprinklers, inline tap, pressure regulator and hose connector. This complete kit is ready to go, just connect a hose and you’ll be amazed how quickly it will pay for itself in terms of time, money and improved productivity.
Automatic Overhead Irrigation is supplied with the added advantage of a weather resistant, battery operated hose end water timer. Essential for those days when you just can’t be there to operate the system manually.
All Polytunnels supplied come complete with two doors. We have hinged and sliding door options...
The top panel is covered in Shade Net to allow ventilation whilst the lower half is covered with polythene to prevent low level draughts.
The Outer Door Frame is 75mm x 47mm, whereas the Inner Door is 50mm x 50mm. All timber used is FSC® certified.
We also offer a DIY option...make your own doors and end frames. If you prefer to build your own bespoke doors - you can exclude the doors and timber end frames and receive a discount.
All door panels are covered with polythene, ventilation is easily controlled as you can slide the doors open to leave any gap of your choice. Sliding doors sit securely on the doorframe, flush to the polytunnel, and out of harm's way.
The Outer Door Frame is 75mm x 47mm, whereas the Inner Door is 50mm x 50mm. All timber used is FSC® certified.
We also offer a DIY option...make your own doors and end frames. If you prefer to build your own bespoke doors - you can exclude the doors and timber end frames and receive a discount.
When you buy one of our Polytunnels you will receive a Free Polytunnel Lucky Bag, consisting of the following:
The two best selling Polytunnel books by Andy McKee and Mark Gatter.
Crop wheel, a wealth of growing information...when to sow, grow, harvest and a really useful measuring device too.
Polytunnel planner, the essential monthly planner packed full of tips and advice.
Tomato seeds, specially selected to help you get your polytunnel growing...they taste yummy too.
Polytunnel Growing Guide, will take you through a whole 12 months of activity in your polytunnel.
At First Tunnels, we really like to reward our customers. Every time you buy a commercial polytunnel or a domestic polytunnel from us, we will offer you great bonus savings based on the value of the goods you are buying. Of course we want you to choose us, for all your polytunnel needs – from the basic structures to all the add-ons that make life just that little bit easier. But with this bonus save scheme, what is good for us is also good for you. The more you buy from us, the greater the discount you will receive on the items you have bought.
There is no need to get out your calculator to work out how much you can save – an intelligent basket system will calculate the savings that will apply on the goods you have chosen while you shop – doing the hard work so you don't have to. If you have almost spent enough to qualify for our great bonus save, you will be informed and will have the option of including another small, useful item in your order and making even bigger savings.
Items such as base rails, sliding doors, crop bars and staging can all improve your polytunnel experience – purchasing them alongside your polytunnel can now help you save money too!
No. When we tell you that you can get great savings, that is what you will get. Our prices are already fair and competitive and these discounts mean even better value for money on our great polytunnels and polytunnel related products.
All you need to know is that bonus savings can only be made when one of our commercial polytunnels or domestic polytunnels, however large or small, is included in your purchase.
No matter whether you are buying a small polytunnel for your garden or allotment or a far larger commercial polytunnel for your business, smallholding or farm, you make great savings of up to 20% on your purchase!
Unfortunately, we cannot offer savings on accessories and polythene covers ordered separately, if a Polytunnel is ordered then there is no limit as to what you can order and save.
