Fire can kill. A badly designed and poorly constructed building, irrespective of the materials used, can be a death trap for those who live or work there. The 2017 Grenfell Tower disaster in London stands as a stark reminder of fire's ability to destroy lives and property. Seventy-two people died, primarily from toxic smoke inhalation, in the capital city of one of the world's richest countries with one of the best emergency services.

Tall buildings, including those built from timber, can be safe buildings with a low fire risk. The issue is not one of material, but of expertise. According to Jose Torero, a world-leading authority on the fire safety of large timber buildings, “Timber can be perfectly safe if it's done right. This is not a technological or technical problem. It is fundamentally a problem of competency. The problem is whether [building designers] are competent enough to be able to make a proper assessment, and that is a much, much more complicated question”.

In this chapter the three main types of structural timber build are discussed in the context of fire: post and beam, timber-framed, and engineered timber. The material that has been used to construct the frame of the building and the material that is preventing the building from falling down is timber and hence we use the term “structural timber”.

Before discussing these different types of timber build in the context of fire, a word about saving lives and saving property. The first is infinitely more important than the second. Burnt out buildings can be rebuilt; burnt out bodies cannot. Hence when discussing fire in buildings the priority is the safety of the occupants and, if a fire does occur, the lives of the attending firefighters.