Protective Underlay for Flexible Pond liners - Water Garden
  • It's important to safeguard your flexible Pond Liner with the use of a puncture resistant underliner.  Water Garden only offer Bonar Yarns UHD Heavy Duty Underlay as this is a high grade material with a minimum density of 250 g/m².  Lower grade materials are not a sound, long term investment and offer sub-standard protection of the pond liner.

    UHD Underlay should be laid on the base and sides of the newly constructed pond before the liner is fitted.  On very flinty soil, we suggest removing any obvious stones and then covering the pond base with 2 inches of sand before the underlay is fitted.

    To work out how much protective underlay you require, we suggest matching the same square meterage as your pond liner.  For example, if your liner measures 4m x 4m (total 16m2), then select 16m2 of underlay using the drop-down tool below.

    View our PVC, GreenSeal, Butyl & Firestone Pond Liners here.

    Find out more
  • Please select from the following options before buying your Protective Pond Underlay
  • QTY

    £48.00 inc. VAT

    £40.00 exc. VAT

  • Please select a product option above in order to add this item to your basket

    Pay in 3 interest free payments of £16.00


Highly puncture resistant polyester membrane to protect against root penetration and stone damage to pond liners. 

Heavy Duty underliner with a minimum density of 250 grams per square metre.

Simple to install, the 2 metre wide roll of underlay can be cut with scissors or a sharp knife.

We suggest allowing 6-8" (15-20cm) overlap between underlay sheets for maximum protection against roots and stones.

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  • Luke Burgess (c/o Elevate Ponds)
    Great product at a great price
    5 stars
  • Tony Appleyard
    Good quality
    5 stars
  • Christine Covil
    Good quality fine for the job, a bit thin but I doubled it up
    5 stars
  • Anonymous
    Excellent quality, plenty to work with.
    5 stars
  • Andrew Feather
    We bought our pond underlay from water garden with quality in mind many inferior products are available but if after doing all the hard graft of digging your water feature you want to finish it properly and this product
    5 stars

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This includes 30cm on the length and width for overlaps. Please use this information to select your pond liner above

Protective Pond Underlay

  • £48.00 inc. VAT

    £40.00 exc. VAT

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