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200gsm Black Flexible Pond Liner with Underlay, 3m x 4m

200gsm Black Flexible Pond Liner with Underlay, 3m x 4m

Regular price £15.69
Regular price Sale price £15.69
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100 in stock

  • Build your garden pond: a 3m × 4m nominal sheet of flexible 200gsm PE for the water-holding layer.
  • Follows your pond's contours: flexible polyethylene fits around curves, shelves and changes in depth without a rigid preformed shape.
  • Black face with grey reverse: UV-resistant PE for outdoor ponds and garden water features.
  • Underlay included: 1 separate 3m × 5m sheet of 50gsm fabric for laying beneath the liner.
  • One liner supplied: cut-size tolerance ±5%. Allow for depth and edging; prepare smooth ground and remove sharp debris before fitting.
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Description

Line the pond contours with a flexible PE sheet

This 3m × 4m bundle brings together a 200gsm polyethylene pond liner and 50gsm fabric underlay. The liner's black face forms the pond lining, with the fabric fitted beneath it as a separate protective layer.

A nominal 12m² rectangular sheet gives more material along one axis. Choose its orientation around the excavation, allowing for the base, side walls, shelves and edges.

One liner · fabric underlay included

Illustrative positioning of flexible black PE pond liner over fabric underlay
Illustrative preparation. Liner and fabric underlay are included; landscaping and installation accessories are not.
3m × 4mNominal liner cut size
12m²Flat liner area
200gsm PEUV-resistant liner
50gsmFabric underlay included

Plan the layers before filling

A carefully prepared excavation supports both materials. The lightweight fabric is part of the preparation, rather than a reason to leave sharp objects in the ground.

Clear the excavation

Remove sharp stones, roots and debris. Smooth the base and supporting sides, including any shelves.

Lay out the fabric

Check coverage around the contours and plan any overlaps. Assess whether your actual ground conditions need additional protection.

Ease the liner into place

Let the flexible sheet follow the shape without tension across gaps. Check the position and perimeter allowance before adding water.

Measure through the pond, not just across it

The 3m × 4m dimensions describe the liner laid flat. They do not describe the pond opening or the finished water surface: the depth and side walls use part of the sheet in both directions.

Measure the longest and widest routes along the actual contours, including shelves, then add the material needed for the edge finish. Compare those two measurements with the 3m and 4m sides. Allow for the ±5% cut-size tolerance, and check the shorter route as carefully as the longer one.

4m3m12m²nominal flat liner areaCut size ±5% · not the finished pond size

Included materials and specification

You receive one nominal 3m × 4m 200gsm PE pond liner with 50gsm fabric underlay. The UV-resistant liner has a black face and grey reverse. Plants, stones, edging and installation accessories are not included.

GSM is weight per square metre. The 200gsm liner and 50gsm fabric have separate ratings; adding them does not describe the liner's weight or thickness. This is a polyethylene liner rather than EPDM rubber.

Choosing and fitting this size

Can I rotate the sheet to suit my pond?

Yes. Position the 4m side along the route that needs it, then check that the 3m side also reaches through its complete contour with enough for the edge finish. Allow for the ±5% cut-size tolerance.

What does the 12m² area include?

It is the nominal area of the flat liner sheet. Material used for depth, sides, shelves and edging is part of that area, so it is not a 12m² water-surface allowance.

Do I need to order underlay separately?

This bundle already includes 50gsm fabric underlay. Plan its layout and overlaps for your excavation, clear sharp objects first, and assess whether the actual ground needs further protection.

Product information & technical details

SKUPLB3X4-001+
Product typePond Liner with Underlay
Size3m x 4m
Length4m
Width3m
GSM200gsm
ColourBlack, Grey
MaterialPolyethylene (PE)
Nominal flat liner area12m²
Included underlay1 × 3m × 5m sheet of 50gsm fabric; separate pieces, allow for overlaps.
Cut-size tolerance±5%

Quantity supplied: one liner with fabric underlay. Intended use: ponds.

All delivery times are estimates and not guaranteed. Orders placed before 1 pm, Monday to Friday (excluding bank holidays), will be dispatched the same day, while orders placed after 1 pm will be dispatched by the end of the next working day.

If an invalid postcode or address is provided, the order will be cancelled without further notice, as we are unable to modify addresses or print labels for invalid postcodes.

Our standard delivery option is Royal Mail Tracked 48, which typically takes 3–5 business days. If you need your order more quickly, Expedited delivery via Royal Mail Tracked 24 is available, offering a 1–2 business day service.

Large or bulky items may be sent via courier at our discretion and are usually dispatched for next-day delivery. Please note that we only ship to mainland UK addresses; delivery to non-mainland locations, including the Highlands & Islands, may not be available for large or heavy items. If your address falls into one of these areas and you wish to purchase such items, please contact us with your postcode and order details before placing your order. If we cannot ship to you, you are welcome to arrange your own courier for collection.

Please see our shipping policy for further information.

All products, unless otherwise stated, come with a standard manufacturer warranty against faulty workmanship.

If your product fails within six months of delivery, please contact us with your order reference number, a description of the issue, and clear images illustrating the fault.

Should your item require a return for further investigation, it is your responsibility to arrange and cover postage back to us.

If we are unable to repair the fault, we may offer either a replacement or a full refund.

In cases where the item is inspected and found not to be faulty, or where damage is determined not to be due to manufacturing defects, you will not be entitled to a refund or replacement. We will then either return the item to you via standard post or dispose of it at your request.

Please see our warranty policy for further information.

You may return any order within 14 days of delivery. As soon as you receive your items, please inspect them carefully, taking reasonable care to keep both the product and its packaging clean and undamaged. If you discover an error or defect after 14 days, we reserve the right to decline your return. If your product fails or breaks after this 14-day time window then your order may be eligible for a warranty claim, please see our warranty information for more details.

To initiate a return, please contact us via our contact form to obtain a return authorisation and the correct returns address (different from the address on your invoice). This can also be done through your 'recent orders' page on your account if you are registered with Shop. Returns sent without prior authorisation will be discarded.

Returned items must be in the same condition in which you received them: unworn or unused, with tags attached and in their original packaging. You must include either a copy of your invoice or a slip with your order reference number inside the parcel. Please be sure not to obscure your return reference number on the label.

If you refuse delivery or reject the parcel without prior notice, we will inspect the returned package and issue a refund upon receipt. Although there is no restocking fee, we will deduct the cost of the return postage label (£3.35) from your refund.

If the returned item or its packaging shows signs of use, damage, or staining, we may deduct up to 50% of the order value, or refuse the return entirely, depending on its condition. Examples include damaged tags, stained, modified or damaged packaging, or missing components.

For faulty, incorrect, or damaged items, please contact us before sending anything back so we can attempt to resolve the issue directly. If we agree that a return is necessary due to our error, we will provide you with a pre-paid return label.

Products that have been modified or damaged through customer action are not eligible for return. This includes, but is not limited to, items that have been cut, trimmed or otherwise altered (such as a tarpaulin or pond liner resized to your specifications), or any product showing damage beyond normal inspection handling.

Please see our refund policy for further information.

All delivery times are estimates and not guaranteed. Orders placed before 1 pm, Monday to Friday (excluding bank holidays), will be dispatched the same day, while orders placed after 1 pm will be dispatched by the end of the next working day.

If an invalid postcode or address is provided, the order will be cancelled without further notice, as we are unable to modify addresses or print labels for invalid postcodes.

Our standard delivery option is Royal Mail Tracked 48, which typically takes 3–5 business days. If you need your order more quickly, Expedited delivery via Royal Mail Tracked 24 is available, offering a 1–2 business day service.

Large or bulky items may be sent via courier at our discretion and are usually dispatched for next-day delivery. Please note that we only ship to mainland UK addresses; delivery to non-mainland locations, including the Highlands & Islands, may not be available for large or heavy items. If your address falls into one of these areas and you wish to purchase such items, please contact us with your postcode and order details before placing your order. If we cannot ship to you, you are welcome to arrange your own courier for collection.

Please see our shipping policy for further information.

All products, unless otherwise stated, come with a standard manufacturer warranty against faulty workmanship.

If your product fails within six months of delivery, please contact us with your order reference number, a description of the issue, and clear images illustrating the fault.

Should your item require a return for further investigation, it is your responsibility to arrange and cover postage back to us.

If we are unable to repair the fault, we may offer either a replacement or a full refund.

In cases where the item is inspected and found not to be faulty, or where damage is determined not to be due to manufacturing defects, you will not be entitled to a refund or replacement. We will then either return the item to you via standard post or dispose of it at your request.

Please see our warranty policy for further information.

You may return any order within 14 days of delivery. As soon as you receive your items, please inspect them carefully, taking reasonable care to keep both the product and its packaging clean and undamaged. If you discover an error or defect after 14 days, we reserve the right to decline your return. If your product fails or breaks after this 14-day time window then your order may be eligible for a warranty claim, please see our warranty information for more details.

To initiate a return, please contact us via our contact form to obtain a return authorisation and the correct returns address (different from the address on your invoice). This can also be done through your 'recent orders' page on your account if you are registered with Shop. Returns sent without prior authorisation will be discarded.

Returned items must be in the same condition in which you received them: unworn or unused, with tags attached and in their original packaging. You must include either a copy of your invoice or a slip with your order reference number inside the parcel. Please be sure not to obscure your return reference number on the label.

If you refuse delivery or reject the parcel without prior notice, we will inspect the returned package and issue a refund upon receipt. Although there is no restocking fee, we will deduct the cost of the return postage label (£3.35) from your refund.

If the returned item or its packaging shows signs of use, damage, or staining, we may deduct up to 50% of the order value, or refuse the return entirely, depending on its condition. Examples include damaged tags, stained, modified or damaged packaging, or missing components.

For faulty, incorrect, or damaged items, please contact us before sending anything back so we can attempt to resolve the issue directly. If we agree that a return is necessary due to our error, we will provide you with a pre-paid return label.

Products that have been modified or damaged through customer action are not eligible for return. This includes, but is not limited to, items that have been cut, trimmed or otherwise altered (such as a tarpaulin or pond liner resized to your specifications), or any product showing damage beyond normal inspection handling.

Please see our refund policy for further information.