“Bang” Machine Testing Dropped, Re-opening Door for Wood Frame Construction into Korea’s Multi-family Sector
Multifamily housing technology has gained a lot of attention in Korea over the last few years as developers seek to improve the efficiency of their existing portfolios of real estate and meet increasing demand for urban housing. However, the entry into this sector for wood construction was interrupted – at least until this August of this year.
For the past thirty years, floor impact noise in multi-family wood frame houses has been evaluated in Korea with a method called the “(big) bang machine”. However, the impact force of the bang machine (4,200 N) is above the range of typical impact forces and the testing method has been long criticized by the Korean wood construction industry for not being able to simulate true-life impact sources.
Technical work by Canada Wood and industry researchers, such as Professor J.H. Park from the Hanyang University, led to the introduction of an impact ball – a standardized impact source with lower impact forces. The 2.5kg weight rubber ball generates a similar impact to the noise of children running and jumping by free-dropping from a height of 1 meter. (Whereas the bang machine consisted of an air filled tire.) On August 4 the Korean authorities announced that the impact ball will replace the bang machine for sound testing of floors.
This regulatory change represents one of several significant steps towards reinstitution of light timber construction in South Korea’s multifamily housing market and mass timber construction.