Root resistance test EN 13948 – FLL

Determination of resistance to root penetration – French laboratory waterproofing systems testing

The CRITT horticole has greenhouses equipments for testing the resistance to root penetration of root protection membrane, roof and waterproof lining sheets and liquid surface treatment material according the European standard EN 13948 and the FLL guidelines for the planning, construction and maintenance of green roofing (2008 edition).The EN 13948 test takes place in a climate-controlled greenhouse during 2 years. The FLL guidelines is a 4 years test in outdoor conditions.

Determination of membrane root resistance according EN 13948

The CRITT Horticole (Center for Innovation and Technology Transfer) and the CSTB (Scientific and Technical Center for Building, European notified body for construction products) have set up a partnership to perform root resistance tests on waterproofing membranes according to the EN 13948 norm (Determination of resistance to root penetration).

During the test, the membrane (bitumen, plastic and rubber flexible sheets, liquid applied kits…) is exposed to root penetration during 2 years in experimental containers. The containers are installed in a specifically dedicated modern greenhouse with climate control system. The CRITT Horticole provides the experimental means and carries out the test in its facilities in accordance with quality requirements of the EN ISO/CEI 17025 norm.

The CSTB operates as test supervisor and administrative responsible. As a TAB (Technical Assessment Body) according to Regulation (UE) N° 305/2011, the CSTB is notified for construction products so waterproofing suppliers can use test results for CE marking and other technical approval procedures.
The CRITT Horticole has research tax credit accreditations.

Determination of membrane root resistance according FLL guidelines

The CRITT Horticole also performs root resistance test on membrane according the German FLL standards. This procedure covers investigations into resistance to root penetration of roots and rhizomes of different test plants in root protection membranes, roof and waterproofing lining sheets and liquid treatment materials for all types of green roofing (extensive and intensive green roofs).

The European norm EN 13948 « Waterproofing membranes, bitumen, plastic and elastomeric membranes for roof waterproofing – Determining the resistance to root penetration » supersedes the FLL procedure.

Both procedure have almost the same identical contents, the differences are the followings :

  • The FLL procedure tests 8 instead of 6 samples for each product tested
  • The FLL procedure takes rhizome forming couch grass as a second testing plant besides pyracantha, while the EN 13948 uses only one test plant : pyracantha