Condensation occurs with fluctuating temperatures and is normal but if left unattended can lead to moisture damage. Shipping Container Homes are prone to condensation due to its airtightness. Moisture is naturally created by certain daily activities such as cooking, washing, bathing and drying. These areas need to be properly ventilated to vent out the warm humid air. This can be solved through proper planning and ventilation of opening up windows and doors. One can also use more active solutions such as dessicants, dehumidifiers and certain linings used.
What is Condensation?
The fog from your bathroom shower or mirror after a hot bath, a few dew drops accumulating under your plant leaves, your car windshield dewing from the fog, or droplets forming on your cold bottled drinks. These are some examples of our everyday encounters with condensation. (1, 2)
Condensation is when the moisture in the air condenses, changing from a gas (vapor) to a liquid (droplets). This usually happens when there is a big difference in temperature between hot and cold. (2)
For container homes, this phenomenon is often referred to as “container rain”, “container sweat” or “wall moisture”. (2)
Shipping containers are securely welded in order to keep their contents safe across oceans makes for a very air-tight home. This is great in a sense that no humid air can enter or seep in. However, it also means any humid air won’t also flow out. (1)
What Causes Condensation in Container Homes?
Our regular bodily activities of breathing and sweating can add moisture to the air. As we see in fogging up mirrors with our breath or the sweat beads that come about after a good workout, we naturally generate a good amount of moisture!
In our homes, think about the areas that have activities that attract a lot of moisture. They are the bathrooms, kitchen, and laundry. (2)
Hot showers, boiling water, and washing your dishes with on a high heat with steam can introduce water vapor into the atmosphere of those areas. This is why it is important these rooms are planned with proper ventilation. It’s also why having an air tight home is not as beneficial in these cases as you would want to let the vapor air out. Washing your clothes, letting them hang to dry, and ironing (as it involves steam) also give the same effect.
Other indoor sources of condensation in our homes, as noted by How to Stop Container Condensation can be the following:
- Non-electric space heaters: Gas, oil-fired, and propane space heaters or wood-burning stoves. Through combustion, they can give off vapor without proper ventilation.
- Damp Building Materials: “green wood”, also known as wood that isn’t fully dried inside, or other materials that may have been exposed to rain and have retained moisture they later on release. This is also an issue if this certain material was closed in during construction. Say partially damped materials have been sealed off in your walls and can cause moisture damage from the inside out.
- Improper Sealing from Moisture: Beware of how snow, rain water and surface water run off can seep into your home if the joints aren’t properly sealed off.
- Plumbing Leakage: Be cautious of any leaks as they are internal problems that are harder to detect. If left unattend can cause bigger problems fast.
- Pressure Differentials: If the outdoor environment has a higher positive pressure than inside, the outdoor air that is warm and humid can be sucked inside, bringing in this moisture in the air.
For shipping containers specifically, these metal boxes sweat when there is a great temperature variance between inside and outside. Just think of scenarios of when there is a significant difference in temperature, like it being hot outside but air-conditioned inside. (3)
“Container sweat occurs when the container walls are cooled to a temperature lower than the dew point of the air inside the container. This can result in moisture collecting and condensing inside the container or on its contents.” – 6 Simple Steps To Prevent Shipping Container Condensation (3)
Besides this, the types of items you have inside your home, like the amount of paper-based and fabrics lying around have a greater ability to absorb moisture.
Another major factor of course will be your climate. Some climates are constantly humid, while others fluctuate frequently. (3)
Shipping containers being airtight can be beneficial in that it does not allow humid air in. However, again, any air that does get in will also stay inside and never leak out. Another factor is that metal is a non-permeable material. This means that any moisture will not be absorbed by the walls as opposed to other building materials. (2)
For a scientific run down on testing for condensation and types of condensation for container homes, check out How to Stop Container Condensation
Why Do We Not Want Condensation to Happen?
As we know, moisture can damage metal by causing it to rust or weaken. The same can occur in brick or concrete that can eventually crack. Wood will also swell, warp and rot or form mold when exposed to moisture and untreated.
Your coatings and paints, equipment, and insulation can also damage and reduce performance. One can also slip from accumulated pools from condensation, becoming a safety hazard. Condensation can also pose a health hazard in the presence of mold growth.
Solutions to Ridding Condensation
There are several solutions we can use to approach condensation problems. In the end, we try our best to avoid it at the planning stage but should they still arise due to unforeseen factors, here are a few things we can try: (2,4)
Home Solutions
Try to control the moisture coming in and out of your building with the following tips:
- Make sure your bathroom areas have excellent ventilation whether its a window or forced with an exhaust fan.
- When cooking, cover up with lids to contain the steam or turn of the exhaust hood above the stove.
- Try to make it that your clothes are drying with the winds blowing away from your home and not into your home. Ensure the dryer vent exhausts to outside.
- Check for any leaks in your plumbing
- Check for any damp or wet building materials before sealing off a part of construction
- Be sure to seal off all joints and seams well from moisture seepage and penetration.
A passive solution, (if your home was planned according to the prevailing winds) is to open your doors and windows to ventilate the space. Have ceiling fans installed, this is a great solution for tropical climates. A more active solution would be switching your air conditioner into “dry mode.” (2)
Ventilation
The simplest, most cost-effective, and most sustainable strategy is to properly ventilate your home.
Of course, this needs heavy consultation from your architects as they carefully study your climate and its effects on your home to achieve natural ventilation. This can mean installing vents into your home or even ceiling fans to move the air and prevent it from being stagnant. The placement of windows and louvers can also be analyzed to maximize airflow in and out of your home. (4)
“The more air you have circulating your house, the smaller the difference between inside and outside temperature, which in turn will reduce or prevent condensation.” (4)
Dehumidifier
These are better solutions for those in cold climates or experience winter seasons. (2)
This turns the moisture in the air into water, so this needs to be emptied out regularly. It’s the easiest solution in that you only need to buy the appliance at the store. However, it does need some maintenance on your part and can consume a lot of energy. Not to mention it takes up precious floor space in our cozy container home. (4)
References:
- Preventing & Stopping Condensation in Shipping Container Home – iContainerHome.com
- How to Stop Container Condensation
- 6 Simple Steps To Prevent Shipping Container Condensation
- How to Prevent Condensation in Shipping Container Homes and Buildings | SHELTERMODE
- How to Stop Condensation in a Shipping Container
