
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.
*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
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 is 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” www.branz.org.nz
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 most effective and important way to keep your home warmer is to install insulation, particularly in the ceiling. It is often relatively simple to install insulation under the floor. Putting insulation in the walls is a major job so it is best done when renovating.
It is better to put a modest amount of insulation throughout the house rather than concentrating on one area or room. If you have to choose, concentrate on the ceiling because this is where most heat is lost. The World Health Organisation recommends a minimum internal temperature of 18°C. Below 16°C there is an increased risk of respiratory disease, so keeping your home warm will help keep you healthy.
From July 2016, grants are available through Warm Up New Zealand: Healthy Homes for ceiling and underfloor insulation for rental properties occupied by low-income tenants.
Visit the Energywise website to find out if you or your rental property is eligible for this funding, or for other information on funding options.
Portions of this were sourced from BRANZ Home Series Bulletin 8 “Reducing heat loss” www.branz.org.nz
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.
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.
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Take the asthma control test to find outAn informative pamphlet on how to keep the home dry, warm and pollution-free.

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