Wood high-rises still contentious ahead of ICC vote
- The International Code Council, which provides the basis for building codes around the world, is set to vote this fall on whether it will back a code change to allow construction of wood buildings up to 18 stories. A public comment hearing after the organization's annual conference in October will be followed by an online voting period of two weeks.
- The ICC's Ad Hoc Committee on Tall Wood Buildings, formed to investigate the science and safety involved in tall wood building construction, approved several wood-related code proposals in April. However, the group has been met with opposition from some industry groups like the Portland Cement Association (PCA) and even its own members. In order to help address concerns, the committee set out to dispel common myths about the proposed code changes and clarify the codes themselves in a response document. Among the committee's statements were assurances that it had based the changes on careful analysis and fire testing, a clarification of the difference between highly flammable "stick-built" construction and mass timber, and an explanation of how they reached fire-resistive ratings.
- The PCA sponsored an 800-participant online survey in which 75% of respondents said they did not believe raising the allowable height of wood buildings was a good idea. When asked why high-rise wood construction was a bad idea, survey participants' answers included that wood was not strong and required more maintenance than other materials (33%); was a fire hazard (31%); would deteriorate faster than other materials (10%) and would be more susceptible to natural disasters like earthquakes and hurricanes (8%).
If the ICC passes the new tall wood building codes, state and local agencies are likely to modify their own regulations to allow for this type of construction, as they do with the other changes the ICC makes. And, as with the ICC proposals, there is bound to be pushback from those concerned about fire safety, although wood advocates maintain that charring of heavy timber actually allows wood structures to maintain up to 90% of their strength during a fire.
Oregon is one state that isn't waiting for the final ICC version of tall wood codes. Earlier this month, the Oregon Building Codes Division issued a statement of alternate method (SAM), which introduced three new types of construction for tall wood buildings. This makes Oregon the first U.S. state to allow construction of wood buildings taller than six stories without a special review process or consideration. The three new categories of wood construction provide parameters for nine-story, 12-story and 18-story structures.
- ICC Ad Hoc Committee on Tall Wood Buildings ICC AD HOC COMMITTEE ON TALL WOOD BUILDINGS RESPONDS TO CONCERNS RAISED ON CODE PROPOSALS ADDRSSING TALL WOOD BUILDINGS (AUGUST 1, 2018)
- Stop Tall Wood Americans’ Views on Tall Wood and Building Safety
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