Wall joint or sound block component and wall assemblies

A fire, smoke, and/or sound blocking head-of-wall assembly that allows dynamic movement, the assembly comprising:

• a header track coupled with an upper surface, the header track having a web and first and second flanges extending from the web in a same direction, wherein each of the first and second flanges is substantially planar such that the track defines a substantially U-shaped cross section;
• a stud coupled with the header track, an upper end of the stud located between the first and second flanges;
• a wall board coupled with the stud;
• a deflection gap with a variable height formed between an upper end of the wall board and the upper surface, wherein the height of the deflection gap is larger in an open position than in a closed position;
• an elongate component to block fire, smoke, and/or sound, the elongate component comprising:
• a first leg having a first end and a second free end opposite the first end, wherein the first leg extends in an upward direction;
• a second leg having a first end and a second free end opposite the first end;
• a third leg perpendicular to the second leg, the third leg having a first free end and a second end, wherein the second end of the third leg joins the first end of the first leq and the first end of the second leg;
• and
• a compressible block positioned on top of the third leg, the compressible block having a lower face positioned on the third leg and an upper face opposite the lower face, wherein when the compressible block is uncompressed, the upper face of the compressible block extends above the second free end of the first leg.