How to prevent a damp, cold and mouldy home

ARTICLE Erin Reilly

Your family’s health

“New Zealand homes aren’t especially good at helping us to stay warm and dry…with one in five people moving out of a house because of factors such as dampness or mould,” says AUT Professor of Sociology Charles Crothers.
“The health implications of a cold damp and mouldy home are phenomenal,” agrees Auckland Refresh Renovations builder. “If you suffer from asthma, which many New Zealanders do, living in a cold, damp and mouldy home will exacerbate the problem.”
Lucky for us, there are confirmed changes to the Residential Tenancy Act which will make homes warmer, drier and safer for New Zealand.
These changes require rental properties to have any replacement or installation of insulation to meet the required standard, and all rental properties to install underfloor and ceiling insulation that meets the standard requirement, where accessible.

The structural integrity of your home

“If water gets into your walls, flooring and other building materials, your home is instantly weakened,” continues the Refresh Renovations builder. “I once visited a home that had mould all down the walls, water coming in through the roof, and wet beams and leaky water pipes under their house. It was an appalling living situation.
“You can do a lot to a house if it’s structurally sound, but in that situation, it was really beyond redemption.”

Don’t forget your wallet

Damp homes hit the wallet hard, says Manukau Refresh Renovation builder Corey Rambhai.
“Damp equals cold,” he says. “It takes much more to heat your house when it’s full of moisture. You can heat it as much as you like, but as soon as you turn the heating off it gets cold again very quickly. Not only is this inefficient, but it also drives up power bills.”
The HRV State of Home Survey backs this up, with some respondents claiming their monthly power bills can get as high as $1,000 because of moisture and poor – or no – insulation.

Insulation

The first step to creating a warm, dry and mould-free home is installing insulation in your ceiling and walls, and under your floor. There are lots of insulation options out there, with the most common being glass wool and polyester-type products.
Insulation is required in the ceiling and underfloors if accessible. If you're renovating the walls of your home, then it is a requirement to install insulation into your walls.

What if you’ve got high ceilings with no cavity to fill with insulation?

“Install a false ceiling,” says the Refresh Renovations builder. “Cathedral ceilings give a great sense of space and light, but they can also be very cold. You only need 175ml or so to build a false ceiling and install insulation, so you can enjoy a warmer home without compromising on that space that many people love.

Ventilation

To have a warm home you need to have a balanced ventilation system. Think about where you dry your clothes - make sure that the moisture is being ventilated to the outside of your home, rather than into your ceiling cavity. Also, get your renovation builder to take a look under the house or under the ground to see what kind of moisture levels are there. If there is an issue, a moisture barrier can be installed to avoid moisture transferring into your home.
Think about your kitchen and bathroom extractor fans, too.
“Drawing steam out of your kitchen, especially rangehoods, or bathroom is great, but if moisture collects in the ceiling cavity you’ll encounter problems further down the track,” says the Refresh Renovations builder. “Always extract moisture from your kitchen and bathroom into the atmosphere, not into your ceilings.”

Double-glazing

“Kiwis like to let lots of light into our homes, especially during summer, so we tend to have a lot of glazing around our properties,” says The Refresh Renovations builder. “Double-glazing lets a homeowner open their home up while keeping the warmth in.”
“Installing new double-glazing on an existing home can be expensive, though,” says John. “If you have existing wooden or aluminium windows, retro-glaze the windows instead of removing them and starting again from scratch – it’s much more economical.”

Heating

Fires, electric heaters and heat pumps are popular heating options, but keep a few things in mind.
“Panel heaters are great, but make sure you get one with a thermostat and timer,” says the Refresh Renovations builder.  “Schedule your heater to turn on and off throughout the day so your home maintains a steady degree of warmth. You don’t have to have it on full-boar; just keep the chill out of the air so when you get home from work your home is much easier to heat up.”
The Refresh Renovations builder warns homeowners against some styles of gas heaters, though.
“Avoid unflued gas heaters,” he says. “Gases generate H2O, so you could find if you use an unflued gas heater, you could also have a damp home.”

Cheaper options

What if you don’t have much of a budget? Fortunately, there are plenty of cheaper – and simple – options to create a warm and dry home.
1. Lay thick building plastic over the ground under your house to prevent moisture build-up.
2. Repair any broken water pipes.
3. Invest in thick, lined full-length curtains.
4. If you’ve got high windows that curtains can’t reach, stick a plastic film over the inside of them to keep the heat in.
5. Use draught stoppers around your windows and doors, and fill in any holes or cracks that could let cold air in.
6. Don’t dry your clothes inside.
7. Put a lid on your shower cubicle to prevent steam from entering your bathroom.
8. Buy a dehumidifier.
9. Visit the Energywise website to see if you qualify for subsidised insulation.
1_The HRV State of Home Survey 2016 was conducted by Buzz Channel with participants sourced from buzzthepeople online research panel of more than 20,000 New Zealanders. We surveyed N=1450 respondents who were between the age of 18 and 74 years. The margin of error on this sample is +/- 3.6% at the 95% confidence level._

You might be interested in reading: Painting Q&A: preparation and removal.

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