Sound transmission loss evaluation of rainscreen wall assemblies; investigation of test specimen installation and comparative evaluation of 54 rainscreen assemblies
Bibliographic record
Abstract
The sound transmission loss of wood-frame wall assemblies with rainscreen cavity and optional split insulation was investigated. New BC building codes and provincial guidelines requires high performance exterior wall assemblies to be designed with the incorporation of rainscreen principles; however the sound isolation performance of these wall assemblies was not addressed. Evidence from previously reported test results suggested an improved overall STC rating is expected for rainscreen wall assemblies; however, the limited data is not sufficient to predict the transmission loss of the currently mandated assemblies. In addition, during the previous evaluations of rainscreen wall assemblies the specimen under test was fully sealed, representing a face-sealed wall assembly, which does not account for the gaps in the cladding required for drainage and ventilation in a rainscreen assembly. Therefore, the prerequisite to evaluating rainscreen assemblies is a specific investigation of the design of the test specimen for acoustical measurements in three conditions: fully sealed exterior cladding, with a single drainage gap, and with a drainage and top ventilation gaps. The result of this study indicated that use of a face-seal wall test specimen to evaluate rainscreen assemblies will results in an under-estimation of transmission loss at high frequencies and critically overestimate transmission loss in low frequencies. The outcome was to include a drainage gap for the evaluation of 54 rainscreen wall assemblies with variation in exterior insulation material, exterior insulation thickness, rainscreen cavity width, cladding attachment, and cladding material layers. Overall tests results showed an expected superior behavior for fiber cement board as cladding; XPS is more sensitive to compounded variables than is rigid mineral wool in the outboard cavity; and resiliency in cladding attachments marginal increases transmission. The OITC and STC ranges over the 54 tested assemblies was 26 to 30 and 37 to 47 respectively.
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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".