Because Dri Flex ties cannot be randomly tested on site, it is necessary to perform comprehensive preinstallation tests.
There are several different methods of performing tests, but the most straightforward way is to drill into both leaves as described in the Installation Procedures section above. The near leaf hole may then be overdrilled to 12mm. The Dri Flex tie should then be installed into the far leaf and a test performed using the Target Load Test Unit. The fixing capability into the near leaf material may ascertained by drilling into the near leaf as in the Installation Procedures section above and inserting the tie to a maximum depth of 80mm and then test using a Target Load Test Unit. It is recommended that testing is performed in accordance with the requirements of BRE Digest 401. Only in exceptional circumstances does the proof test load requirement exceed 1kN.