Specification

Sizes 

Haygrove Garden Tunnels are available in two widths, 3m (9’8”) and 4m (13’1”). 

The lengths available range from 6m (19’6”), and then increase in 2m increments, up to a maximum length of 20m (65’6”). 

Steel Frame

Our Garden Tunnel frames are made completely from galvanised steel including doors, side vents and the base anchoring system.

The grade of steel is specified as E320. This is the structural grade of steel used in building and construction and not the mild steel grades that are often used to cheapen products, but will not perform in heavy winds. Galvanisation is to the British Standard of 275g/m2.

Our Garden Tunnels are mounted on a steel skid plate that forms the perimeter base of the structure. This means that the structure is completely fixed to the ground and there is no need for the polythene to be dug into the soil.

As the polythene does not need to be buried into the ground, you can simply remove the anchors and move your Garden Tunnel to a different site! 

The Haygrove Garden Tunnel cover is a high quality coated woven polyethylene material – UV treated to ensure we can guarantee it for 5 years against UV degradation.

The material is 172g per sq m in weight and due to being woven it’s extremely strong, with a breaking strength of 18kg per sq cm or 255llbs per sq. inch! The woven property also means that a cut in the cover does not run and can be patched up with repair tape. 

The material has 88% light transmission which means that it generally performs better than glass which has a light transmission of 65% to 85% depending on the pane size and glasshouse structure.

In addition the material has an additive that diffuses or scatters the light when it enters the polytunnel. This means that the light is more available and gets deeper into the canopy of the plants and there is less direct radiation and risk of scorch on the upper leaves of the plant.

The light diffusing nature of the plastic is demonstrated because on bright sunny days there is very little shadowing in the polytunnel.

Every Garden Tunnel comes with a steel-framed door at one end for access. On all sizes of polytunnel there is the option to upgrade to two doors, one at either end. 

As well as being used for access, doors are an effective way of managing ventilation. When the doors are shut they give an excellent seal to maintain the temperature in the tunnel. When the doors are open they allow air to flow freely into the polytunnel. 

On Garden Tunnels over 10 metres, we would recommend having two doors to ensure good airflow, especially on hot summer days. 

The doors are a standard width of 1m (3ft 3”). Wide enough for wheelchair access and perfect for the wheelbarrow! 

Anchoring

In each 2m section, there are 4 steel anchors that are driven at a 45° angle into the ground. Each anchor is 0.8m (2’6’’) long and is made out of 3mm galvanised reinforced steel bar. If you are looking to position your polytunnel on hard standing, Garden Tunnels can also be bolted to concrete or tarmac. 

Side Height

The A-frame shape of the Garden Tunnel gives a side height of over 2m (6’6’’) even to the edge of the polytunnel. This maximises the growing space in your polytunnel for tall plants and means less awkward bending over for you!