Repair the air path without defeating drainage

A repair must close the intended air path while preserving the water path. New material evidence can invalidate an otherwise sound detail.

Original case · Suggested 15 minutes · Edition 2026-10-12.1

By the end of this workshop

Choose a method that respects the supplied conditions.
Explain how a changed condition affects the decision.
Identify a physical or procedural cross-check and an applicability limit.
Record the assumption you would verify next time.

Start with the complete model

Givens and assumptions

The exterior membrane is the documented continuous air-control layer. The window head return has an untaped air gap; both jamb transitions are connected.
Head flashing drains outward and sill weeps are open. Field air testing locates leakage at the head return.
An approved compatible transition system is available to connect the head return to the frame while preserving flashing laps and weeps.

Study calculator, scratch notepad and whiteboard

Expression Trigonometry in degrees

Supports +, −, *, /, ^, parentheses, sqrt, abs, log (base 10), ln, sin, cos, tan, pi and e. Confirm units independently.

Scratch notepad

Scratch text and drawings stay in this tab and clear when you leave or reload. Save important reasoning in a response or reflection below before leaving.

Scratch whiteboard

Sketch a control volume or air path with a mouse, pen or touch. Ink stays in this page session and clears on reload. Use the response and reflection fields as a keyboard alternative. Sign in before starting and save a reflection to retain your reasoning.

1 · Choose the method

Which response addresses the supplied head-return air leak while preserving the documented water path?

Choose one responseInstall the approved head transition; preserve flashing and weeps.Seal all sill weeps; use the existing head flashing as the air seal.Add cavity insulation; retain the untaped head gap for air movement.Paint the gap with any available coating without compatibility evidence.

ConfidenceWhy did you choose this method? Optional personal reasoning, up to 1,000 characters.

2 · Change the condition

Predict before you inspect the calculation.

The contractor substitutes a transition product with no compatibility approval for the installed membrane and frame.

The same head air gap needs repair while head flashing and sill weeps stay functional. The proposed substitute has no verified compatibility or approved substitution; the original compatible system remains specified.

Check the first decision to open the changed-condition response.

Personal notes are not automatically graded. Workshops are linked learning experiments, separate from timed diagnostics and mocks. They do not predict a pass or award instructional hours.

Reference navigation drill

Search concept: air-barrier continuity, flashing, submittals

Mark the intended air and water paths independently. Identify the document needed to accept a substituted transition.

Use an authorized reference. A search term does not guarantee that a current examination reference contains every relationship used in this teaching case.

Where this model stops

Original coordination facts; real assemblies require project details, manufacturer instructions, material compatibility and applicable code. This case does not identify a real defective product.

NCARB · ARE 5.0 ↗

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