Roof, wall and foundation transitions · Lesson 3 of 4

Roof, wall and foundation transitions: methods and worked application

A transition schedule, the nine checks in order, a reroof datum example with tapered insulation, the build order at a rising wall, a sidewall and a wall base, stepped flashing on sloping ground, a screed buried by landscaping, and the shop drawing check.

You will be able to: Apply a nine-check method to a roof, wall and foundation transition set, fixing the datum for every height, working a reroof, a stepped wall base and a planting-bed example with every assumption labelled, and checking an AFS shop drawing against the schedule.

11 min · 11 slides · 7 questions

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Slide 1 of 11

A transition schedule

Hutchinson advises drawing in each layer of insulation and its attachment method.

A transition schedule lists, for each transition, the layers on both sides, the piece that joins them, the datum, the measured height, the governing document and the trade.

This is a working method, not a code requirement; it makes every number name its source and its datum.

Sources

The Integration of Roof and Brick Requires Concise Details, page 3 (T. W. Hutchinson, Roofing magazine, 21 November 2016) - Roofing magazine
Insight-050 Parapets: Where Roofs Meet Walls (J. W. Lstiburek, rev. 2012) - Building Science Corporation

Videos for this lesson

What this video shows: The International Masonry Institute's clip on a low roof to high wall detail, where the work of one trade stops and another begins.

Video: A.31 Roof to wall detail by International Masonry Institute, on YouTube. Chosen from the video's published description.

Glossary

Transition schedule: A table the designer builds listing each transition, the layers on both sides, the joining piece, the datum, the measured height, the governing document and the trade; a working method used in this module, not a code term.
Tapered insulation: Insulation laid in a slope to drain a roof; added at a wall it raises the roof surface there, which Hutchinson notes can rise above an existing through-wall flashing at a reroof.
Stepped flashing: Base-of-wall flashing laid in steps where the grade slopes, with the higher end of each piece turned up as an end dam and the higher piece lapping the lower by 4 in minimum (BIA).
End dam: A turned-up end of a flashing piece that stops water running off the end and sends it to the weeps; BIA calls for one at the higher end of each step.
Interior gutter: A designed gutter at a wall, used at a reroof so the existing through-wall flashing can stay in place (Hutchinson).