Building codes help improve energy efficiency, yet mother nature creates another problem. Old homes are often draftee, lack energy efficiency, as such moisture balances (humidity) between the outside and inside of the home. Costs more to heat, yet at the same time climate equilibrium is reached. Newer homes, energy efficient spaces, do not allow climate equilibrium, simply put, and condensation forms on the warmer side during colder days.
Every modern home faces this issue in one way or another. Some cheaper windows may have drains at the base of the window to allow moisture move outside. Most new window frames do not have this, as this contravenes energy efficiency.
New homes use more fixed panel glass (non-opening), so the frames are not designed to mitigate water, just hold the glass in place. Most apartment buildings will have limited opening windows due to wind considerations assessed during the planning stage. These may include no windows on certain sides of a building or above a certain level.
The consequence of condensation is mould. Once mould forms, it is extremely difficult to get rid of it. If mould enters walls and grows through them, the only way to remove it is to replace the entire wall / roof panel, as cleaning it will not remove it from within the panelling (plaster, etc). The same goes for flooring, if mould grows from under carpet or other flooring, you will need to replace that section of flooring completely.
The simplest method is to mitigate condensation and control it so that mould never grows in your home.
How To Fix The Problem?
Door / Window opening – The cheapest of all methods, open a window or door and leave slightly ajar at night, and dress warmer to live within your home. This helps keep the humidity stable. You may need to turn on a ceiling fan in some rooms that have poor ventilation, OR, if you heat your bedroom, you will have condensation that you must deal with another way for that room. End of the day, most of your home will not have condensation issues using this method.
Window Vacuum – The next cheapest is to use a window vacuum every morning on all windows affected with condensation. This would need to be done first thing in the morning, as once the sun hits the window, condensation will pool and disperse from your window frame.
Dehumidifier – This is the optimal solution for modern homes / apartments during winter. A 20lt dehumidifier, centrally located, will sufficiently remove condensation from forming. Turn it on before going to bed, and empty it in the morning. Place it centrally on low fan and constant condensation removal, and you will have no issues.
Reverse Cycle Air Conditioning – This is probably the most expensive of the fixes, is to run a reverse cycle split system on automatic at a given temperature. Automatic includes the dehumidifier, which will keep the space condensation free. You can also run just the dehumidifier mode, but you’re still paying for a large system to work, so no matter what setting, your electricity use will be significant.
Personal Melbourne Apartment Experience
We live in a 100sqm apartment, we have used all of the above methods. When we go away during winter, we leave a door / window ajar, and run ceiling fans to equalise air flow, and we have no condensation issues when away from our apartment. When home during winter, we now use a 20lt dehumidifier, centrally located, which is more than enough to keep our apartment condensation free. We run it every night, and usually for 24hrs twice weekly, to keep the space dry. We also found that by running the dehumidifier, we used less heating, as the dehumidifier affects the temperature by putting dry air into the space.
We have tried the window vacuum, and its painful to do that every morning. We have used our split system, and its expensive and still doesn’t do as good a job as the central dehumidifier.
We’ve had guests in our home during winter who mention, how do we keep our place from the damp smell during winter, as most places they enter smell damp. That is all from a single 20lt dehumidifier. We turn it on before going to bed, we let it run until about 8am on winter mornings. Really cold nights it will be full, but using it how we do, where we run it for 24hrs twice weekly, we tend to not fill the unit the majority of the time, cold or not. We found that running it twice weekly for 24hrs keeps all the condensation build-up that happens within furniture and fixings to a minimum, thus how full the unit gets each night is then controlled so it doesn’t fill and auto turn-off.
Obviously smaller spaces will have less issue with the unit filling, but our experience is a guide for anyone using a separate dehumidifier to keep their space dry during winter.