Deflection Drift Angle
US Patent #8,595,999 B1 (Deflection Drift Angle) is a composite steel angle with intumescent tape factory applied to the inside leg of the steel angle.The DDA is a fire-rated accessory that when combined with slotted or deep leg track will offer 2” unencumbered movement at the head-of-wall joint in accordance with UL-2079 “Test for Fire Resistance of Building Joint Systems”. The 2-1/2” outside leg marked for proper identification. The section is fabricated from minimum 0.018-inch thick hot-dipped red galvanized steel complying with ASTM A653 having minimum G-40 coating.
- The DDA provides a universal fit for any wall width, gauge, height, radius, pitched, shaftwall or standard wall.
- Easy installation; DDA is tapped in to place over the leg of the track, the ¾” leg is friction fit between the overhead structure and the web of the header track
- There is no need for mechanical fasteners the DDA’s friction fit provides fire and smoke protection during both vertical and lateral drift movement.
- The DDA comes in 10’ lengths with 10 per box up to 2” unencumbered movement with positive stud attachment
- DDA butt joints are over lapped.
- When fire spray is required Rectorseal brand fire sprays are required on ONLY ONE SIDE of the wall.
- Over 20 separate UL reports in accordance to UL2079 “Test for Fire Resistance of Building Joints”.
- Maintains best possible L Rating (smoke rating) and NO loss of STC sound ratings at head of wall joint.
- Uses up to 75% less fire spray with the majority of the joint systems requiring no fire spray at all.
- DDA and Rectorseal brand fire spray offer an industry best sustainable-life warranty
- DDA and Rectorseal brand fire sprays and sealants are 100% made in in the USA
- All Engineering Judgments utilizing fire spray or fire sealant are provided by Rectorseal
DDA not only meets all current building code deflection requirements but it can also provide fire, smoke and sound protection for drift & lateral movement. DDA is the first of its kind to provide unencumbered movement in both vertical deflection and lateral drift movement in a joint system that utilizes fire spray over mineral wool on just one side of the wall.
DDA has no restrictions providing 100% unencumbered movement. DDA has been tested for compliance with Section 713.3 of the 2006 and 2009 IBC and 2007 CBC and is listed with UL Underwriters Laboratories in accordance with:
- UL 2079: Tests for Fire Resistance of Building Joint Systems.
- ASTM E 1966: Standard Test Method of Fire Tests of Firestop Systems.
- ULC S115-M95: Standard Method of Fire Tests of Firestop Systems.
- ICC ESR-2012
Whether the protection you need is Fire, Smoke, or Sound, DDA will help you achieve your requirements. Sound tests were performed at Western Electro-Acoustic Laboratory in Southern California to prove that the DDA will maintain maximum STC ratings without secondary acoustic sealant applications. In fact several sound tests were conducted both with a ½” to ¾” open joint at the head-of-wall and with a sealed head-of-wall joint on the same wall assembly. Both open and closed joints rendered the exact same STC rating proving that no sound is lost through the open head of wall joint.
Unlike fire or acoustic sealants that will crack and split with minimal movement the DDA will provide protection for the most extreme real life conditions and allow your head-of-wall joint to freely move both lateral and vertically without ever compromising the sound (STC) rating.
DDA is approved for Class III cycling requirements, 500 cycles at 30 cycles per minute, meeting seismic building codes requirements. The class III movement provides design advantages over mastic reliant systems which are currently limited to class II (wind sway) capabilities of 500 cycles at 10 cycles per minute.
AIR LEAKAGE RATING
Air leakage tests conducted for compliance with Section 713.6 of the 2006 IBC and 2007 CBC are witnessed by UL on conditions using DDA as the joint treatment established L-Ratings of less than 1 CFM per lineal foot. Any rating below 1 CFM is also considered the best possible L-Rating.