Tips for healthy homes

Healthy Home

Living in a dry and warm environment is good for everyone, but for people with a respiratory condition it is vital for them to stay well. 

Many houses are damp and cold, leading to more colds and flu which aggravates respiratory conditions. Making your home dry, warm and pollution-free will make it a healthy home and also save you money and energy.

How to stay dry and keep moisture out

  • Put lids on pots when cooking
  • Dry clothes outside
  • Vent your clothes dryer to the outside
  • Air your house on fine days
  • Air clothes, shoes and wardrobes regularly
  • Use extractor fans or open windows in the kitchen and bathroom to remove moisture
  • Remove mould or mildew from walls, shower curtains, etc. with a fungicide e.g. very diluted household bleach.
  • Check for water leaks from guttering, plumbing etc, and have them repaired
  • Ensure that there is adequate drainage around your house
  • Black plastic on the ground under the house will keep it drier and easier to heat
  • An in-roof ventilation system will reduce condensation
  • Consider double glazing if you are building or replacing windows

How to stay warm and keep heat in

  • Have well-fitting curtains and pull them at night to keep heat in
  • Use draught stops under doors and draught proofing strips around windows and doors
  • Use a healthy form of heating such as a flued gas heather, heat pump, pellet or wood burner
  • Insulate your ceiling and under the floor to keep heat in and heating costs down**

*Unflued gas heaters release moisture and harmful gases into the home

**40% of heat can be lost through an uninsulated ceiling and 10% through the floor

How to stay pollution-free and keep air clean

  • Make your home smokefree. Stop smoking or smoke only outside
  • Use an electric or flued gas heater rather than unflued gas heaters
  • Air your house on fine days
  • Limit the use of strong-smelling cleaners, air fresheners and flysprays
  • Keep dust to a minimum – dust with a damp cloth and vacuum regularly
  • Consider hard floors and rugs, ideally with underfloor insulation, instead of fitted carpets

Dealing with Condensation

Condensation occurs when water vapour is converted into liquid water. If the air temperature drops, at night for example, some of that moisture will be released when the warm air comes in contact with a cooler surface like a wall, ceiling or window pane and then droplets of water form on the surface. This contributes to mould growth and makes houses feel colder and more difficult to heat. Mould is also a trigger for asthma.

Our daily habits create a cycle of condensation – even morning showers and cooking breakfast produce water.  Ventilation is important for reducing and controlling condensation. Fortunately it takes just a little effort to do this. The cheapest and most effective method is to have windows open a small amount over long periods of time. (Security concerns can be addressed through fitting security stays or fitting aluminium windows with passive ventilation and condensation channels.) Externally vented extraction systems in the kitchen (range hood) or bathroom (extraction fans) will reduce moisture levels significantly. Close doors to the bathroom or laundry if large amounts of water vapour are being produced so that it doesn’t spread throughout the house, and open the window in those rooms to allow water vapour to escape

Portions of this were sourced from BRANZ Bulletin 367 “Condensation”

Dealing with dampness

Damp homes can cause health problems for the people who live in them, and they are more difficult to heat. It is important to try to identify the causes of the dampness and correct them. If a home is insulated, ventilated and adequately heated but dampness and mould growth continue, it is likely that moisture is coming from damp ground beneath the floor, from rainwater leaking into the home, or from leaks in plumbing.

Many of our homes were built before insulation was required to be installed and unfortunately many homes were never retrofitted with insulation. About 40% of heat can escape through an uninsulated roof and 10% through an uninsulated floor. No curtains or badly fitted curtains also allow heat to escape. Similarly, gaps under doors or around windows also make it hard for us to heat our home. Many people just give up trying to heat their home adequately because with all the ways in which heat can escape, but these problems can be fixed.


The World Health Organisation recommends a minimum internal temperature of 18°C – or higher if people in the home have health conditions or are elderly.

Quality, well-installed ceiling and underfloor insulation is the top priority for a warmer, healthier home. Wall insulation is best installed when you are renovating and replacing wall linings.

Check out whether you are eligible for a Government Warmer Kiwi Homes grant offering ceiling and underfloor insulation and/or an efficient heater. Grants are for lower-income homeowners living in their homes and cover 90% of the cost (heaters capped at $3,000, including GST). 

Reducing draughts will reduce heat loss for relatively little cost:

  • block off open fireplaces if they are not in use
  • use draught stoppers to close off the gaps under doors
  • use draught strips or seals on windows and doors
  • good fitting curtains reduce heat loss at night and keep in the heat gain from the sun during the day – to be effective the curtains must fit snugly to trap a layer of air between them and the glass
  • double-glazing can halve the heat loss of single glazed windows but you’ll still need curtains.

Portions of this were sourced from BRANZ Home Series Bulletin 8 “Reducing heat loss”

What kind of heating is best for my health?

First you need to think about the size of the area that you want to heat – is it large or a small room? How cold does your part of the country get? When and how often you want to heat each space – only for short periods? Do you want instant heat or can you wait for a wood burner to heat up? The costs of the appliance and running it are also important considerations. Some options should be avoided if at all possible. Open fires are inefficient, polluting, expensive and hard to control. Portable or bayonet fitting unflued gas, kerosene or LPG canisters and heaters release pollutants and water vapour into your home. Don’t use these unless you absolutely have to and particularly not in bedrooms or small unventilated rooms.


(information sourced from EECA)

For larger rooms that you want to heat regularly, like a living room, it’s worth paying a bit more upfront for a fixed heater with lower running costs and more heat output than a small electric heater can provide. This could be a modern wood or wood-pellet burner, an energy efficient heat pump, or a four-star qualified flued gas heater.

Electric heaters may be enough for smaller rooms and rooms you only heat occasionally, like bedrooms. Avoid unflued gas heaters (with pipes fixed to the walls or portable) which release toxic fumes and moisture, and open fires which are draughty and inefficient 

Find out if you qualify for a Warmer Kiwi Homes grant for an efficient fixed heater for the main living area

Heating options

Heat pumps

Heat pumps are an efficient form of heating although there are significant differences between appliances. It is important to get one that is a good fit for the size of the area that you want to heat and if you live in one of the colder parts of the country, check that it will work effectively when the temperature drops below 10 degrees Celsius.

Wood burners

These can be cheaper and produce a lot of heat. Newer models create little air pollution and are relatively efficient. It is important to use dry, well-seasoned wood from sustainable sources (dried for at least a year).

Gas heaters

Flued gas heaters are an effective form of heating. They are also healthy because the products of combustion are removed from the house. Unflued gas heaters, by contrast, should be avoided if at all possible. They emit nitrogen dioxide which is particularly bad for people with asthma and also water vapour that will make the house damp and more difficult to heat.

Wood pellet burners

Wood pellet burners are an efficient and environmentally friendly form of heating. They burn pellets made from waste wood, in a controlled manner and have a low level of emissions. They only use a small amount of electricity.

Electric heaters

Electric heaters include radiant, fan, convection and night store heaters and underfloor heating. All of these operate differently and have different pros and cons. A portable heater can be useful for heating a small room for a short period or where the heat is for one person.

Central heating

Central heating heats up either water or air that is then used to heat the entire house. Hot air is distributed in a series of ducts while hot water systems may involve radiators or pipes built into the floors. The heat may be generated by gas, a wood pellet-fuelled boiler or heat pumps. Many of these systems have controls that allow you to control the temperatures in different parts of the house, for example, bedrooms can be kept a little cooler than living areas.

The Asthma and Respiratory Foundation acknowledges the use of the EECA energywise action sheet in preparing this information.

Read how to become smokefree.

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Healthy Home Checklist

Home Sweet Healthy Home

A useful checklist identifying the key steps to creating a dry, warm and healthy home for you and your family.