Envelope failures are almost never material failures. Brick does not fail. Membranes do not spontaneously fail. Junctions fail, and they fail because nobody drew them at a scale where the failure was visible.

Four rules

One: every junction gets drawn at 1:5. Two: water has to have somewhere to go at every horizontal. Three: the airtightness line is a single unbroken pencil stroke on every section, or it does not exist. Four: if a detail needs more than one trade on site at the same time, redraw it.

The cost of getting it right

Our standard detail set took two years to write and costs roughly 1.5% of fee to maintain. It has eliminated envelope defects across eleven completed buildings.