HOT, WET SUMMERS, HIGH LEVELS OF HUMIDITY + LITTLE CHANGE BETWEEN DAY/NIGHT TEMPERATURES
- Movement of air is an important
- Open up houses as much as possible
- Use lightweight materials for the walls and roof
- So they do not store much heat and shed heat quickly
- ie steel or timber stud frame with metal, timber or fibre cement claddings
- Avoid Heavy mass products, such as brick and block
- Such mass re-radiate the heat they have stored during the day, which keeps the house hot after sunset
- If must use, ensure they are well shaded
- Windows should be shaded from the sun and protected from rain
- The roof and/or ceiling should be insulated and roof space is well vented
- Living room + bedroom has at least two openings
- The building should be engineered to withstand cyclones
- Develop a long, thin floor plan with as many rooms as possible having windows or openings on at least two walls to achieve maximum cross-ventilation
- Provide covered external living areas that are positioned to catch the prevailing breezes in both the wet and dry seasons
- Insulate the eastern and western walls
- Using lighter, more reflective colours on roofs and walls
- Raise the ceiling height to greater than 2700mm or using sloping ceilings with a minimum height of 2400mm
- Choose windows that catch the breeze and can be left open in wet conditions,
- ie louvres, casements or awning windows
- Use awnings to shade windows and provide rain protection
- Put high level windows or vents in all rooms, to let out the hot air and draw in cooler air
- However it is important that windows or vents can be closed in storms
- Avoid shrubs and dense planting up to 2100mm high that will block breezes, make internal rooms darker, and provide breeding areas for mosquitoes and other pests
Design for Natural Ventilation
- Use the breeze for cross ventilation through openings in opposite walls and internal partitions
- Maximise the area of windows (e.g. louvres) that can be opened
- Orientate house to catch the breeze (whilst still minimising sun on east and west walls)
- A long narrow floor plan catches the breeze best.
- Trees and shrubs act to cool the air passing through the house.
- Don’t use exposed concrete on ground immediately outside the house as it heats the air.
- Roof space ventilation draws the heat out.
- Dirty flyscreens block more breeze. Consider using openable/removable flyscreen shutters
Minimum Insulation Standard
- Light coloured well ventilated roofs: foil/sisalation
- Other roofs: R1.5 batts and foil/sisalation
- Full shading of wall is much more important than wall R-value. Unshaded, masonry walls store heat and release it well into the night.
- Shelter windows with louvres, canopies, shutters or fixed overhangs – then you can enjoy the cooling effect of rain.