Beware of air moisture and don’t let your floors cup or buckle this summer, but if you have problems, JD Enterprise in Denver is ready to help you repair your floor. According to a Wood Floor Business article, your wood floor is affected by the moisture in the air. Air with a high moisture content (MC) or high relative humidity (RH) can cause wood to collect moisture, which causes it to expand. When this happens, your wood floor may become distorted, resulting in your floor cupping and buckling.
Buckling is when a plank has begun to separate from the sub-flooring. Cupping is when the edges of a plank begin to rise above the midsection. Crowning is when the midsection begins to swell above the edges.
To avoid this, there are some things you should know about summer moisture:
- Warming air lowers its relative humidity
- Cooling air raises the relative humidity
- Cooling air too much causes condensation
- Outside air contains moisture
How can you control moisture by choosing your wood flooring material and planning installation?
There are some things you can do to improve the moisture conditions of your wood floor including:
- Acclimate the flooring the right way
- Use narrower boards
- Choose stable species of wood
- Use quartersawn boards
- Choose approved vapor barrier membranes or system for concrete slabs
- Accept some gaps
- Use products that are good in high relative humidity environments
How does moisture in the air affect your wood flooring?
To control summer-related flooring expansion, let’s first examine the environmental control of summer moisture issues.
Relative Humidity-Most mornings start out cool and humid, often causing dew to form on your grass. By afternoon, the air warms, the relative humidity drops and the dew evaporates. However, at night the air cools again and the humidity goes up and dew forms.
The amount of water in the air remains about the same every day, but because of the relationship between temperature and relative humidity, when the temperature changes, the relative humidity changes.
Dew point-This tells the amount of water in the air. It is the temperature (which can vary according to the pressure and the humidity) below which water droplets begin to condense. The dew point is different in different locations. For example, on a typical summer day, the dew point may be near 45°F in the Southwest, 55°F in the Northwest, 65°F in the Northeast, and in the upper 70s along the Gulf Coast. In winter, the dew point temperatures can be well below freezing.
Building Temperatures-Of course, the inside temperature of the building with the wood floor is important also. Many buildings are air conditioned which create a cooler temperature inside than outside. The area under a building is often cooler than the inside the building. This cool soil keeps slabs, basements, and crawl spaces cool as well. Ductwork in basements or crawl spaces can also help keep those areas cool. The summer air is warm and humid but the indoor surfaces are cool.
Moisture can enter through a crawlspace or basement foundation walls, from the exposed soil in a crawl space, or from activities in your home. Add that to the fact that cooling air raises the relative humidity and that creates some potential for problems with your hardwood floors.
Ventilation as a Moisture Source-Lots of people ventilate these spaces to try and control the moisture levels. Depending on where you live, the amount of moisture that needs to be removed in the summer will be different. But when warm outside summer air enters a house and cools, the relative humidity of that air increases. To get the relative humidity back down, the moisture needs to be removed. The more ventilation, the more moisture is going to get into the house.
So reducing ventilation can help remove moisture. Weatherization and home energy audits typically measure ventilation rates and can pinpoint leakage sites. Old windows are often major leakage sites, as are recessed lights, and other holes in ceilings and floors.
Warmer outside air requires more moisture removal. Higher ventilation rates require more moisture removal, and lower target indoor relative humidity levels require more moisture removal. Since the ventilation rate and moisture removal are connected, you should reduce ventilation rates before you try to remove moisture.
What are the best ways to avoid distortion to your wood?
According to the Wood Floor Business article, there are some ways to get rid of the moisture and protect your wood floor from cupping and buckling, including reducing ventilation, control water in crawl spaces or basements, add dehumidifiers, modify your AC system and of course, choose appropriate wood flooring.
Removing Moisture-Moisture is removed from indoor environments by ventilation and mechanical systems.
Ventilation-Ventilation with dry air can help dry out a house, but this air must be cold to be dry enough to be helpful. If the dew point is below 60 degrees, venting can assist in drying your house. If the dew point is above 60 degrees, then venting will just add moisture to your house. So except for some arid or cool parts of the country, venting to dry a house in the summer is not a good idea.
Mechanical Systems-So that leaves us to use mechanical systems like air conditioners or dehumidifiers.
Air Conditioning- A typical air conditioner uses about 25 percent of its energy to get rid of water from the air. A three-ton air conditioner can remove about nine pints of water per hour when it’s running wide open. An air conditioner only removes moisture when it is running. A properly sized AC runs wide open about 1 percent of the year. The rest of the time, it won’t remove nine pints per hour.
On a hot day, the AC may run 90 percent of the time in the afternoon, but only 10 percent of the time first thing in the morning. The outside dew point remains the same, so that means the same amount of moisture needs to removed in the morning and night to maintain the same indoor relative humidity.
But in the morning it may only remove one pint per hour because the air conditioner isn’t running much. Once the indoor temperature is cool, the air conditioner shuts off. But moisture is removed only when the air conditioner runs. An oversized air conditioner can cool the house quickly, but because it doesn’t run very long that means it doesn’t remove moisture very well.
Dehumidifiers- A central or whole-house dehumidifier is a good solution for humidity control in many buildings and homes. Good systems put close to 100 percent of their energy into removing moisture and can handle up to around 6.5 pints per hour, every hour, regardless of mild weather or cool mornings when an AC won’t run very much.
Dehumidifiers will shut down when an air conditioner can handle the moisture loads. And since dehumidifiers turn on and off because of humidity levels, you don’t need an oversized air conditioner and you don’t have to leave the fan on.
You can try portable dehumidifiers but they’re not usually as effective. They don’t remove much more than about two pints per hour, and they often use more energy than a whole-house dehumidifier. They can help in one room, but that leaves humidity control lacking in the rest of the house.
Dehumidifiers are good in basements because the surfaces in basements are cool, and an air conditioner won’t run much.
An unvented crawl space with a dehumidifier can be an efficient way of controlling humidity levels below wood floors that are over a crawl space.
We know that air with a high moisture content or high relative humidity can cause wood to collect moisture, which causes it to expand. If this happens, your wood floor may become distorted. Don’t let your floors cup or buckle this summer. But if anything happens, we can help. At JD Enterprise in Denver, our flooring experts can help you refinish, repair or replace your wood flooring. We’ve been in the Boulder since 2000 but we serve the entire Metro Denver, Boulder, and the Front Range of Colorado.