Comparing life cycle implications of building retrofit and replacement options
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
When is it better to retrofit a building as opposed to demolishing and rebuilding it? Life cycle environmental and economic analyses are used to address this question through the study of a typical four bedroom detached house in Toronto. Three vintages of the reference house are used: 1930s solid masonry; 1960s wood frame; and post oil crisis, 1980s wood frame. Retrofit studies considered include insulating the attic and basement walls and air leakage sealing. Over a 40-year life cycle, the rebuild option has lower life cycle energy, global warming potential, and air pollution, which are predominantly associated with building operation. But the retrofit options have lower water pollution, solid waste generation, and weighted resource use, associated with material flows. The retrofit options also have lower life cycle economic costs than rebuilding. In this respect, the preferred options are basement plus air leakage sealing retrofit for the 1930s house, basement retrofit for the 1960s house, and no change for 1980s house. There are ways to overcome the trade-off in negative environmental impacts between retrofitting and rebuilding, such as use of renewable energy sources or re-use and recycling of deconstruction and demolition materials in new construction.Key words: life cycle assessment, life cycle costing, building retrofits, sustainable development.
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.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 it