{"product_id":"allpondsolutions-pond-underlay-2-x-15m-150gsm-non-woven","title":"AllPondSolutions Pond Underlay 2 x 15m 150gsm Non-Woven","description":"\u003cp\u003eAllPondSolutions is proud to offer our own branded pond underlay. This is 150 grams per square metre of 100% virgin non-woven polypropylene, and it is the layer that stands between your liner and whatever is buried underneath it.\u003c\/p\u003e\n\u003cp\u003eThis piece is 2 x 15m and covers 30 square metres, our largest. It is the most economical way to underlay a big pond, and one roll will cover a 5 x 4m or 6 x 4m liner on its own.\u003c\/p\u003e\n\u003ch3\u003eWhy underlay matters\u003c\/h3\u003e\n\u003cp\u003eA pond liner rarely fails because the material is poor. It fails because something sharp was left underneath it. As the pond fills, the weight of the water presses the liner hard onto whatever is below, and a stone, a root or a fragment of glass will work through it over a season or two.\u003c\/p\u003e\n\u003cp\u003eUnderlay is the cushion that stops it. It also lets gas from the soil escape sideways rather than collecting in bubbles beneath the liner.\u003c\/p\u003e\n\u003ch3\u003eCheck the weight of \"free\" underlay\u003c\/h3\u003e\n\u003cp\u003ePond liners are often sold with free underlay included. It is usually around 60 g\/m2, which is thin enough to tear on the first sharp stone it meets. Ours is 150 g\/m2, two and a half times the material, in the place it matters most.\u003c\/p\u003e\n\u003ch3\u003eHow much do I need?\u003c\/h3\u003e\n\u003cp\u003eAllow the same area as your liner plus about 10% for overlapping the pieces. It does not need to be a single sheet: lay pieces side by side, overlapping each by 5 to 10cm, and work outwards from the deepest part of the pond. Do not tape or glue the joins, as the overlap is enough and it lets trapped gas escape.\u003c\/p\u003e\n\u003ch3\u003eLaying it\u003c\/h3\u003e\n\u003cp\u003eClear the excavation of every stone, root and sharp edge you can see, then run your hand over the surface to find the ones you cannot. Start at the bottom and work up the sides, carrying the underlay past the rim so the liner never touches bare ground. Lay the liner on top, then trim both back together once the pond has filled and settled.\u003c\/p\u003e\n\u003ch3\u003eUse it on top as well\u003c\/h3\u003e\n\u003cp\u003eIf you are adding gravel, cobbles or rock, or building a stream, lay a second layer over the liner first. Sharp stone dropped onto a bare liner is one of the most common causes of a leak.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSize: 2 x 15m, covering 30 square metres\u003c\/li\u003e\n\u003cli\u003eOur largest piece and the best value per square metre\u003c\/li\u003e\n\u003cli\u003e150 g\/m2 non-woven polypropylene\u003c\/li\u003e\n\u003cli\u003e100% virgin fibre\u003c\/li\u003e\n\u003cli\u003eRot resistant and permeable, so gas and groundwater can escape\u003c\/li\u003e\n\u003cli\u003eInert and safe for fish and plants\u003c\/li\u003e\n\u003cli\u003eOverlap pieces to cover a pond of any size or shape\u003c\/li\u003e\n\u003cli\u003eRequired for the guarantee on AllPondSolutions HDPE pond liners\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"AllPondSolutions","offers":[{"title":"Default Title","offer_id":56421013619067,"sku":"APS-PU150-020X150","price":59.99,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0733\/7220\/5341\/files\/APS-PU150-020X150_2x15m.png?v=1789571534","url":"https:\/\/www.allpondsolutions.co.uk\/products\/allpondsolutions-pond-underlay-2-x-15m-150gsm-non-woven","provider":"AllPondSolutions","version":"1.0","type":"link"}