Evaluation of Air Leakage Properties of Seam-Fastened Mechanically Attached Single-Ply and Polymer-Modified Bitumen Roof Membrane Assemblies
Bibliographic record
Abstract
The National Research Council of Canada (NRCC) in collaboration with the Canadian Roofing Contractors Association (CRCA), National Roofing Contractors Association (NRCA), Roofing Industry Alliance for Progress, and the Single-Ply Roofing Institute (SPRI) addressed the issue of air movement in roof assemblies through a research and development project designated air movement impacts on roof Systems (AIR). The AIR steering committee developed goals for a two-phase testing program: Phase 1, quantify air permeances of single-ply and polymer-modified bitumen membrane materials; and Phase 2, quantify air leakage rates of seam-fastened mechanically attached single-ply and polymer-modified bitumen roof membrane assemblies. In Phase 1, four roof membrane materials were tested using ASTM E2178 test protocol to measure the air permeability rates. The tested materials meet the air permeability criterion of ASHRAE 189.1, ASHRAE 90.1, and the International Energy Conservation Code (IECC) for effective air barrier materials. In Phase 2, a test method for measuring air leakage rates across membrane roof assemblies was developed. Test assemblies were constructed with seam-fastened mechanically attached Phase 1 roof membrane materials, rigid board roof insulation, and steel roof decks. Each test assembly also included five common roof penetrations flashed in accordance with the manufacturers' installation instructions. The results demonstrated that the tested assemblies comply with ASHRAE 189.1, ASHRAE 90.1, and the IECC air leakage requirement for effective air barrier assemblies. An ASTM work item under the D08 committee is underway on the developed test method for measuring air leakage rates across membrane roof assemblies.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".