The 01' Professor

摘要

Fairfax county, virgini, had a fire that started on a rear decik of a townhouse and communicated to exposures on both sides. In Montgomery County, Maryland, a burning porch collapsed on a firefighter. The porch was lag bolted to a ledger board and thus appeared to be substantial, but the ledger board was not adequately attached to the house. A few years ago, a porch in Prince George's County, Maryland, collapsed under the weight of several people. The "sturdy" ledger boards had been nailed into the ends of 2 × 2 top-on-bottom flanges of the wooden I-beams. The same was true for all the houses in the development.