Buying a Polytunnel: What to Look For & Questions to Ask

A well-made polytunnel can be a game-changer for any keen gardener or professional operator. Choosing the right polytunnel supplier is one of several key choices. With the many polytunnel companies to choose from, there are options available. It’s very easy to make a rushed decision, but by investing time into research, planning, knowing what you intend to grow and asking the right questions, you will save money and avoid stress in the long run. Polytunnel companies are experienced professionals.

Important Things to Look for When Buying from a Polytunnel Supplier

Professional polytunnel companies use coated galvanised steel or strong aluminium frames when they either supply or install.  Aluminium is much lighter, a little less robust, and not as sturdy when used on heavier, complex or multi-connected builds. The choices of materials used in builds when purchasing from professional polytunnel companies ensure their products meet the environmental demands and stress of UK locations they are placed in.

Your polytunnel supplier should be able to answer questions about preparation, installation, construction or other concerns, such as frame and cover quality, strength, and build materials used in the kit or for a bespoke structure.

Polytunnel Companies Provide Manufactured Polythene of Quality

Most professional polytunnel companies will supply standard UV-stabilised coverings that last from 4 to 5 years from 120 to 150 micron on small garden structures or thicker heavy-duty polythene with at least a 6 to 8-year expected lifespan, using layered or insulated thicker materials 180 to 200 plus microns plus far more robust and resists tearing better and provides better insulation, normally used for covering commercial polytunnels or if requested for specific bespoke builds, check with your polytunnel supplier.

Good Ventilation and Access

Either single entry or doors at both ends, good ventilation is required for controlling humidity and temperature. Poor or badly managed ventilation can lead to plant stress, disease, and heat buildup.

Discuss options with your polytunnel supplier. Do you need roll-up sides, additional vents, or a covering that better suits the intended crops or plants to be grown? The related size of the tunnel will mostly decide the ventilation requirements.

Size and Design for a Planned Layout

What shape and size of a polytunnel are most suitable for a beginner or someone new to permaculture? For serious gardeners or those growing produce to sell, a larger one is often necessary. Always provide enough space for your crops and plants by considering their size, spread, and height when mature, ensuring it's comfortable to walk around and has enough working space to access all parts.

Anchoring and Other Ground Fixings

How will the tunnel be secured? Options include base rails, ground tubes, anchor plates, or trench foundations.  Based on your local seasonal weather conditions, soil type, wind exposure and surrounding environmental stresses.

Ease of Installation and Assembly

Some kits are truly DIY-friendly, while complex or bespoke builds may require more technical skill or a small team to assemble, depending on size. Look for clear instructions and support availability. Check all of the above with your polytunnel supplier.

Some Questions to Ask Before Purchasing

1. Check what the quote covers

2. Warranty on the frame and the polythene cover?

3. Are there upgrades or bespoke build options like crop bars, staging, slide doors or other venting options, etc?

4. What design performs better in harsh and strong rain, winds or snow?

5. Is delivery included, and how are the parts packaged?

6. Do you offer assembly support or guidance for installation?

7. What happens if parts are missing?

8. Does a self-build affect the warranty?

9. What is the lead time from order to delivery?

Asking polytunnel companies questions helps avoid cheap and poorly manufactured kits that may be unsuitable for your particular growing environment and location in the UK, when using all year round.

Visiting your Local Polytunnel Supplier in Person?

When making a sizable investment, especially for bespoke or large domestic and complex commercial-sized tunnels, paying a visit to the polytunnel supplier can be a good way to confirm your choice:

• You can inspect the materials and walk inside a model tunnel to get a feel for size and build quality

• Staff can walk you through modifications or accessories tailored to your needs.

• A local visit gives insight into how the company treats its customers and how easily you can get support later.

• They can advise you on absolutely everything from anchoring systems, ventilation, and layout, based on location, climate, and soil type, to what you will need for year-round use.

Final Thoughts

Buying from polytunnel companies directly offers peace of mind, and it isn’t just about picking a size and price that suits your pocket; it’s about matching the tunnel to your growing goals, site conditions, and long-term goals. By asking expert polytunnel companies who understand your requirements, they know exactly what you will need, asking relevant questions, and, if possible, visiting the polytunnel supplier, you are better equipped to choose a lasting investment that can better meet and support the demands placed on it to complete your growing success. 

Read More:

Polytunnels and Miniature Cultivation Is an Entrepreneurial Niche

Common Polytunnel Repairs: From Garden to Commercial Scale