Field evaluation of ventilation wetting and drying of rainscreen walls in coastal British Columbia
Bibliographic record
Abstract
The climate in southern coastal British Columbia (BC) is characterized by a long rainy winter. Building envelope failures that have occurred in recent years in this region promoted the adoption of the rainscreen principle in both rehabilitation and new construction and are now mandatory in the wet regions of Be. In addition to the functions of a capillary break and drainage, drying in an air cavity behind the cladding of the rainscreen wall system may occur through cavity ventilation. Current practice varies in terms of cavity depth and vent heights for rainscreen walls clad with panel systems, especially with respect to the top slot vents. The awareness of potential drying provided by cavity ventilation initiated the idea of providing top vents on brick veneer walls recently in the BC construction industry. However, there exist different views on the drying provided by cavity ventilation based on existing research. Whether cavity ventilation would be beneficial for this climate remained open for discussion. To answer this question, a comprehensive research program was designed by Dr. Hua Ge with the candidate using a two-storey building envelope test facility at British Columbia Institute of Technology (BCIT) which Dr. Hua Ge developed. The candidate investigated twelve wall specimens, six clad with brick veneer and six clad with fibre cement panels, installed on the southeast façade, which faced the prevailing wind-driven rain direction. The test variables include cladding type, air cavity depth and height, vent configurations and initial moisture load in plywood sheathing to evaluate the impact of cavity ventilation on the drying and wetting of test walls. The hygrothermal conditions across the wall assemblies were monitored for moisture content (both resistive and gravimetric), temperature, relative humidity, air speed in the cavity and pressure differentials between top and bottom of each cavity. The on-site weather conditions were measured including wind speed, wind direction, solar radiation, horizontal rainfall, and wind-driven rain. Indoor conditions were controlled at 22±1°C and 55±5% RH In this study, the drying and wetting rates of plywood sheathing in the test walls during the winter and spring seasons were quantified, under-cooling effects on the temperature of cavity-surfaces of claddings and plywood sheathing were analyzed and the daily hours of condensation on the cavity-surface of claddings for all test walls were calculated. Simulation and measurements of MC in plywood sheathing for two brick veneer walls and two fibre cement walls were compared.
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 | 0.001 | 0.001 |
| Science and technology studies | 0.003 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".