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Newton 409 Root Barrier 1.2m x 50m

£385.00 Ex VAT
£462.00 Inc VAT

Eliminate root penetration in green roof systems with Newton 409 membrane.

Puncture Resistant Root Barrier

Newton 409 root barrier membrane is an efficient and effective way to prevent root damage in green roof systems.

With high tensile strength and puncture resistance, this impermeable HDPE membrane protects your primary waterproofing membrane from root damage. As a green roof barrier membrane, it provides reliable protection from roots, including aggressive root systems like Japanese Knotweed.

Uses of Newton 409 Root Barrier

The Newton 409 root barrier membrane provides protection from roots in a green roof system. It is also suitable for use within planters.

Installing Newton 409 Root Barrier

Once a primary waterproofing membrane has been applied, you can roll out the Newton 409 RootBarrier membrane.

Note: It should be placed above the primary waterproofing and sometimes above the Newton 407 DeckDrain if this has been specified as part of the system.

Cut the root barrier membrane to size with a utility knife or shears. Subsequent lengths of membrane should be placed next to each other, overlapping by at least 150mm. These joints should be sealed with two lines of double sided Newton Waterseal Tape.

If you need to cut holes for any pipes or ducts, you should patch with pieces of the membrane and seal with Newton Waterseal Tape.

For more information read our green roof design and construction how to guide

Permagard - Providing Solutions. Inspiring Confidence.

Permagard are proud to stock a wide range of Newton membranes and waterproofing products. If you have any questions about Newton green roof or drainage membranes contact our technical team on 0117 982 3282. 


  • Cost effective root barrier
  • Eliminates root penetration
  • Quick and easy to install
  • Excellent chemical and biological resistance
  • Suitable for existing and newly planted trees and plants
  • Lightweight
  • Durable and puncture resistant
  • Resistant to sea water and fertilisers