Moving into a brand new home is an exciting time. Fresh walls, carpet and cabinets all lie ready for your belongings to turn the space into a welcoming home for you and your family to enjoy. 

There are many benefits to living in a newly constructed house, including the fact that they’re generally warmer and easier to heat than many of the older homes around the country. However, new homes can actually experience high levels of internal moisture for up to two years after construction.

There are a few different sources of moisture and knowing about these potential issues will help you be more prepared before you either start building or once you move in. Read on to learn about where the moisture in new homes comes from and what you can do to prevent it both during and after construction.


Where Does Moisture in the Home Come From?

Moisture in a home — such as condensation on windows — can be extremely annoying to deal with, but sadly it’s unavoidable. Moisture finds its way in through a variety of sources. Knowing how and when moisture is elevated will better equip you to tackle it before it turns into problematic damp.

steaming pot

Internal Moisture

The biggest sources of internal moisture comes from things vital to our everyday human activities and they’re not exactly things that we can stop doing. 

Activities in the kitchen produce up to four litres of water every day through cooking and doing the dishes. An easy way to reduce this is using lids on as many pots and pans as possible to reduce the steam vapour escaping into the room. Meanwhile, the bathroom is responsible for 1.5 litres of moisture per day, per person thanks to showers and baths. 


In both the kitchen and bathroom, having an extractor fan (or rangehood in the kitchen) is really important to ensure the steam is quickly whipped away from the room and doesn’t have the chance to turn to damp, mildew and mould in the house.

New builds can also experience internal construction moisture from a different source: building materials. During the building process, moisture gets trapped in construction materials such as concrete and timber, which can take a long time to completely dry. Sources vary but it could take between one and two years for a new home to completely dry out[1]. During this time it’s important to make sure you home is properly heated, well-ventilated year-round and sufficiently insulated. 


External Moisture

Moisture doesn’t only come from inside the home, there are many external moisture sources as well. These outdoor sources can be bad for your home’s health, seeping into the house and causing issues that often aren’t seen until it becomes a costly problem to fix.

One big contributor to external moisture can be inadequate drainage. If your home has broken, blocked, leaky or poorly connected guttering or pipes then water could be escaping and finding a way to cause dampness issues. This can be a problem that takes a bit of time to fix and the best way is to inspect your pipes and guttering during a downpour to ensure it all drains away correctly. When you move into your new home, take a look at how the drainage is performing when the first bout of heavy rain hits!

Although your home might be new, the roof can be another area that lets water inside. If your roof is flat, has parapets or has roof-to-wall junctions then it’s more prone to leaks than homes without these features and you should bear this in mind in case issues arise.

Finally, a home’s windows can also be a source of external moisture. Condensation on windows is a problem a lot of homes suffer from and even double glazing isn’t a solution. Window flashings can also be a problem for external moisture, however this is generally a problem for older homes where the flashings have deteriorated over the years. 

condensation on window

Are You Building a New Home? Here are Some Tips:

While you may not necessarily have the skills to actually construct a new home, making yourself knowledgeable about how to ensure a sturdy new build is still a great move. 

The first step towards a safe, comfortable home is choosing the right people for the job. Not only does this mean skilled and reliable building professionals, but those who will complete your home in line with the Building Code. Whether you’re building a house, townhouse or apartment, you may find that you need a licensed building practitioner (LBP) to carry out certain important work. 

When your home is being designed, keep in mind that it’s good to plan for passive ventilation. Having a home fit for passive ventilation means having doors, windows, vents, louvres and other openings that will bring adequate amounts of fresh air inside, allowing the old air to escape. This is a must-have for any home, though for a long-term solution you could also consider installing a home ventilation system.

To make sure no moisture makes its way into your home from outside, install a ground moisture barrier under the house. This barrier — made of thick polythene sheeting — will make sure that any rising damp coming from the ground under your home won’t make its way to the floor of your house.

Proper insulation is one of the biggest ways to kick excess moisture to the curb and these days it must be installed in every newly built home in New Zealand. Having sufficiently insulated walls, ceilings and floors will make a home less prone to moisture and damp and therefore drier and easier to heat. 

We talked earlier about areas of the home that are frequently exposed to excess moisture, including the bathroom and kitchen. Because of this, it’s very important to make sure the rooms are adequately fitted with extractor fans. Find one that can handle the amount of moisture the room will be exposed to.

Aside from considering extractor fans for these rooms, also think about their position in your home. It’s important for moisture to be taken from the kitchen and bathroom and deposited outside. While you’re in the design phase, consider whether moisture will be able to be vented outdoors with ease, or if the room’s placement will make that tricky.

While older New Zealand homes usually have single glazed windows, these days double glazing is much more commonplace for new homes. Having double glazed windows in your home means that it’s harder for heat to escape and therefore your home should retain warmth for longer — perfect for those long, cold NZ winters. They also help reduce noise, making your home a quieter, warmer environment.

It’s important that all homes are ventilated, but even more so with new homes that need to dry out after construction. Having your home installed with a home ventilation system is an easy way to ensure you never have to worry about this. 

A home ventilation system is installed in your roof space and works to replace the air in your home continuously. For example, HRV’s ventilation systems replace the air up to three times every hour. A home ventilation system can be installed in existing homes but having one put in during the building phase ensures that it’s there from the beginning of your home’s life, quietly working to reduce moisture.


Properly Ventilate During and After Construction


Ventilation allows fresh air to circulate your home. While it’s important in both new and old buildings, if you live in a new home you should be particularly vigilant in order to reduce internal moisture. 

Passive ventilation is an option for new homes — and your home should have been built with this in mind — but having a home ventilation system installed helps ventilation happens automatically, without you having to worry. A home ventilation system will also filter the air before it gets into your home.

If you’re interested in learning more about options for your new home, book in a free home assessment. HRV offers full home solutions and the sooner into the building process we can form a plan for your home, the better! Contact the HRV professionals today.