The excess air pressure from a nuclear explosion may be of the order of 28 000 kg per square meter (40 pounds per square inch). This may be compared to normal roof loading, for instance 200 kg per square meter (100 pounds per square foot). This ratio happens to be around 140, but it could be much higher closer to a blast. The Department of Defense has sponsored graduate‐level courses on “hardened” construction, in which the author participated. Advice was given against such construction as glass‐front office buildings. An alternate construction has been envisioned by the writer, in which the excess pressure on the building would be reduced by pressure‐relief ports (a patent on this has expired). It is hoped that a combination of hardened frame and yieldable front would provide an economical compromise for semi‐hardened construction. This might have application to tornado resistance as well as nuclear attack.