Understanding the Conditions in Under-Heated Problem Dwellings

1. 10 slides max!! Understanding the Conditions in Under-Heated Problem Dwellings Joseph Little - BArch, MRIAI, MSc Archit. AEES

2. PROBLEM DWELLINGS 10 slides max!! There can be four parties responsible for problem dwellings: 1) The builder/developer - who may have wanted too high a profit, or set too small a budget to do a good job, may have hired an inadequate team, & may even have wanted corners cut 2) The design team - which may have agreed too low a fee to do the job properly, may have resourced the project inadequately and inspected it insufficiently, or been compromised in their role by the very nature of the builder/developer model 3a) The careful occupant - who faced with a badly-built apartment responds by turning the heat down (“I’m damned if I waste further money”) and switches the intermittent fan to manual control, or 3b) The unthinking occupant - who blocks vents, frequently dries clothes in small rooms and (perhaps) likes lots of stews! Too often the whole problem is blamed on the occupant 4) Lastly the government - which has under-resourced building control for over two decades, and has unwittingly allowed inadequate guidance, like Part F (ventilation), to negatively effect the air quality of the homes of thousands of families

3. PROBLEM DWELLINGS 10 slides max!! To deal with the physical conditions that help create fuel poverty we have to analyse what happens in problem dwellings. What prevents even & adequate air & surface temperatures? Quality of construction, insulation continuity & airtightness Heating equipment (location and specification) Heating regime What prevents ventilation maintaining low humidity & good air quality? Quality of construction, window & background vents design Extract ventilation (type, spec. and location Ventilation regime

4. PROBLEM DWELLINGS 10 slides max!! To deal with the physical conditions that help create fuel poverty we have to analyse what happens in problem dwellings. What prevents even & adequate air & surface temperatures? Quality of construction, insulation continuity & airtightness Heating equipment (location and specification) Heating regime What prevents ventilation maintaining low humidity & good air quality? Quality of construction, window & background vents design Extract ventilation (type, spec. and location Ventilation regime Often, not always, occupant issues Related to the other three parties This presentation focus on conditions in one boom-time apartment, only 5 years old. It is not the worst case, but it is instructive

5. THE APARTMENT north Bed #2 Living area Bed #1 Kitchen Hall Bathroom Corridor Entrance door

6. ITS STRUCTURAL PROBLEMS

7. ITS STRUCTURAL PROBLEMS thermal bridge thermal bridge moist grout in pre-cast wall moist air

8. INADEQUATE HEATING The area where heat is needed most to deal with surface condensation & thermal comfort Electrical convection heaters in bedrooms Heat sources in middle of plan Storage heaters in hall and Livingroom

9. INADEQUATE HEATING Heating regime Occupant comment about electrical convector heaters: “I hate using them, they’re just too expensive”

10. INADEQUATE HEATING Heating regime - Visit on 9/12/2011 Heat loss & thermal bridges along external envelope 14°C 14°C 11°C 12°C L 15°C 17-18 16.5°C 23-21°C 16-17°C occupant is gaining heat from neighbour! 45-119°C 17.5°C 18.5°C 18.7°C 42-30°C B#1 17.8°C 49.3 %RH Hall K

11. INADEQUATE VENTILATION Duct runs this long, especially when shallow (i.e. 25 x 300mm) create much resistance Kitchen extract duct (6.5 – 7m) Bathroom extract duct (6.5 – 7m) Intermittent extract fan with 5 minute over-run

12. INADEQUATE VENTILATION Logged data from bathroom of apartment - 25th July – 11th August 2011 Temperature quickly returns to normal From a health point of view it has been recommended to maintain the relative humidity below 45% for some time each winter to reduce the dust mite population. At 22°C this corresponds to 7 g water vapour per kg air (ref: Korsgaard J. (1983)) Temperature (°C) 90% increase in moisture content When showers aren’t daily this appears to be base moisture content 10 Moisture content of air (g/Kg of air) Even after 24 hours ventilation does not return to baseline

13. IMPROVING VENTILATION In order to minimise ceiling heights (& extra cost to developers) ducts for fans were typically 300 x 25mm. These have 4 times resistance of ducts 204 x 60mm It appears the bathroom extract was sized to meet the min. flow rate of 15 l/s. We calc’d ~ 51.5 Pa static pressure due to length & type of ducts, bends & grille 22 l/s suggests an allowance of 40% was added to 15 l/s 51.5 Pa However, whether due to too small a flow rate, too short an over-run or restrictions in ducts, this system is not delivering healthy conditions ~22 l/s

14. IMPROVING VENTILATION Note: DEAP assumes 0.5 ACH is delivered through infiltration & ventilation We have followed old guidance from the UK - other countries have far more specific and onerous ventilation requirements : we suggest revision is needed A big difference in requirements is evident comparing standards from elsewhere (USA, France, Australia, etc) In France, Poland Germany they have used humidity-triggered ventilation systems for many years – these ventilate till humidity levels are low and healthy Aereco, GlidevaleiMEV, Lunos are some of the systems

15. IMPROVING VENTILATION Revised Regs (TGD F-2009, 1.2.2.12) for single-sided apartments requires low & high level openings, or openings & passive stacks to rear Kitchen extract duct (6.5 – 7m) Air rises vertically in passive stacks

16. IN CONCLUSION Unless we understand what are the causes of the various, & often inter-related, issues in a problem dwelling we will not solve this part of the fuel poverty triangle We need: Far more rigorous examination of the causes of problem dwellings Like the Stamford Brook studies in the UK we need all parts of the construction industry to understand their part in what goes wrong Could a conference focus on this issue specifically? We need changes to guidance (like Part F) so that minimum standards support healthy conditions We need properly resourced building control Thousands of tenants of social housing & owners of boom-time dwellings are experiencing conditions that they may, or may not, be exacerbating but that they did not create They need our support Thank you

17. 10 slides max!! Joseph Little - BArch, MRIAI, MSc Archit. AEES consult@buildinglifeconsultancy.com