BRANZ report No. ST0583. Appraisal completed & issued on 8th April 2010
BRANZ - SCREW BOLT Result
For both internal & external walls, fasteners securing bottom plates to concrete floors shall have a minimum capacity when tested within NZS3604 as follows
In the plane of the wall………3604 Spec 4 kN (internal) 5kN(external)
FORTRESS SCREW BOLT = 12.95 kN
Out of the plane of the wall…3604 Spec 3 kN (internal) 4kN(external)
FORTRESS SCREW BOLT = 5.58 kN
‘Pull out’ tension of the fastener… 3604 Spec 8kN (external walls only)
FORTRESS SCREW BOLT = 23.55 kN
BRANZ report No. ST0583. A copy of this report is available on request
Technical Comparison
HANDIBRAC Panel Hold Down Bracket
- The Gib Handibrac has been developed in conjunction with MiTek
- Specifically designed for superior bracing of internal and external walls
- Ultimate tension uplift of 15 kn. M12 X 150 Fortress Screwbolt meets this requirement
- Handibrac has been designed as a substitute for the pre-fitted double strap
FAQ’s
Q: Do I have to use a Screwbolt for an ordinary bottom plate fixing?
A: No, a Fortress 12 x 135 Through Bolt is fine in this situation. It has a capacity of 12.2kN.
Fortress Screwbolts will not cause blow-outs in header block foundation which can occur with a Through Bolt.
|
Load Requirement & Direction |
|
In Plane (kN) |
Out of Plane (kN) |
Tension (kN) |
NZS3604:1999 Standard Bottom Plate Fixing Current (No change) |
5.0 |
4.0 |
8.0 |
Q: Can I use a Through Bolt in a bracing situation?
A: No, we recommend a Fortress 12 x 150 Screwbolt. It has a capacity of 15kN
Q: Can I use a Through Bolt in a braced wall if I use Screwbolts in my Handibrac’s?
A: No, as per Table all anchors used in a braced wall must have a capacity of 15kN.
Q: Do I have to use a Galv Screwbolt in bracing situations?
A: No, not necessarily. ZC is fine in dry internal locations, not subject to airborne salts or rain wetting. In these situations ZC will give a service life of 50yrs, as required by NZS3604:1999
We do stock Galv Screwbolts if required for specific Situations
Bottom Plate Anchors
Build February/March 2008 Issue
Calls to the BRANZ Helpline indicate that there is still confusion about the correct use of bottom plate anchors with concrete floor slabs...
Read full article »