Table 3

Building performance and indoor environment conditions in the English stock for present day (baseline) and cumulative health effect after 50 years for selected exposure-specific diseases under the 2030 energy efficiency retrofit experiment with ventilation scenarios

BaselineExperiment ventilation scenarios
Intervention stockRegulationInstaller discretionNo added ventilation
SampleN
 Dwellings (1000s)18 99017 35017 320
 People (1000s)44 74041 13041 060
Building characteristicsMean (SD*)
 Fabric heat loss (W/K)294 (167)219 (120)213 (115)213 (116)
 Ventilation heat loss (W/K)75 (45)70 (42)51 (35)50 (33)
 Heat system efficiency (%)76 (12)88 (11)89 (10)89 (10)
 Permeability (m3/m2/h)16 (5)11 (5)11 (5)11 (5)
Exposure†Mean (95% credibility intervals)
 Standardised indoor temperature‡ (°C)17.8 (0.7)18.1 (18.1, 18)18.1 (18.1, 18.1)18.1 (18.1, 18.1)
 STS§0.5 (0.4)0.5 (0.5, 0.4)0.7 (0.7, 0.6)0.7 (0.7, 0.7)
 Indoor¶ PM2.5 (μg/m3)9.4 (5.4)4.6 (4.4, 4.2)10.6 (10.1, 9.6)11 (10.5, 9.9)
 Outdoor PM2.5 (μg/m3)6.2 (1.7)6.8 (6.5, 6.2)5.9 (5.6, 5.3)5.8 (5.5, 5.2)
 Radon (Bq/m3)22.9 (14.1)22.4 (20.3, 20.1)34.2 (30.7, 30)35 (31.3, 30.7)
 Mould (% with MSI >1)14.9 (7.5)12.3 (11.6, 11)18.5 (17.8, 16.2)18.8 (18.3, 16.5)
 Heating energy (MWh/year)22.9 (10.4)16.6 (16.4, 16.3)15.7 (15.6, 15.4)15.6 (15.5, 15.4)
Health impact**Total QALYs per 10 000 persons (95% credibility intervals)††
 Cardiovascular (winter)119 (106, 131)69 (57, 81)65 (53, 77)
 Heart attack312 (287, 336)−232 (−279, −185)−271 (−319, −223)
 Stroke306 (282, 330)−258 (−310, −206)−296 (−349, −242)
 Cardiopulmonary1268 (1169, 1371)−44 (−83, −6)−130 (−166, −96)
 Lung cancer233 (209, 258)−75 (−93, −57)−97 (−115, −81)
 Common mental disorder2 (2, 4)3 (3, 4)3 (3, 4)
 Asthma (children)1 (4, 7)−1 (−8, −4)−1 (−9, −5)
 Net impact2241 (2085, 2397)−539 (−678, −399)−728 (−864, −592)
  • *Standard deviation is given for building characteristics as a measure of spread.

  • †Weighted average values of kitchen (10%), lounge (45%) and bedroom (45%).

  • ‡Average between living room and bedroom temperature when 5°C outdoors.

  • §STS 1=average exposure level of smoking household.

  • ¶Indoor sources of PM2.5 relate to cooking only with an emission rate of 1.6 µg/min.

  • **Cardiovascular disease is modelled with equal risk across the population and toxicity of indoor and outdoor PM2.5 is considered equal and as such the results are likely overestimating the impact—see uncertainty analysis for tests.

  • ††Credibility intervals are derived from Monte Carlo analysis showing using the 5th and 95th centiles from 1000 model iteration results as limits.

  • MSI, mould severity index; PM2.5, particulate matter with a diameter of 2.5 μm or less; STS, secondhand tobacco smoke; QALYs, quality adjusted life years.