Humidity fluctuation question

[Manu]

Few things here...

Condensation on windows happen because the surface of your window is cold due to outside temperature. This will happen especially if you have curtains blocking air movement. It's nothing to worry about and doesn't mean your house is rotting. Similar phenomenon to entering your house from cold weather with glasses on, they fog up right with away.. the cold glass will become fogged up even with 30% humidity.

High humidity is not bad for your health, it's actually a good thing for breathing. Think of sick kids in winter, you add a humidifier in their rooms because the air is too dry...

Warmer air can hold more water. I maintain 60-70% humidity and there is no condensation on walls or wood structures.. I keep my temps around 23 24 day time. I will get window condensation if curtains are closed at night. As long as you have air circulation and temperatures are not too low, high humidity is a good thing for your health and your plants!

---------- Post added at 11:34 PM ---------- Previous post was at 11:10 PM ----------

And to answer your initial question, the fluctuation will not harm the plants as long as they have sufficient humidity/are watered adequately. Warmer air will hold more moisture therefore dropping RH. When the sun is strong, or when the heat is on, your RH will drop. The same occurs in nature in most areas that have clear blue skies and reasonable humidity levels. During the peak warm hours, humidity drops and raises back in the evening/night/morning.

[katrina]

Originally Posted by Manu

Few things here...



High humidity is not bad for your health, it's actually a good thing for breathing. Think of sick kids in winter, you add a humidifier in their rooms because the air is too dry...

Warmer air can hold more water. I maintain 60-70% humidity and there is no condensation on walls or wood structures.. I keep my temps around 23 24 day time. I will get window condensation if curtains are closed at night. As long as you have air circulation and temperatures are not too low, high humidity is a good thing for your health and your plants![COLOR="Silver"]

---------- Post added at 11:34 PM ---------- Previous post was at 11:10 PM ----------

Pushing it to 60-70% on a consistent basis...even at those temps...could create problems, over time. Some viruses thrive at higher humidity (the flu!), as do dust mites, fungi, and molds/mildew. And, unfortunately, a lot can be going on behind walls that you can't see. By the time it becomes evident...the problem is huge. I had a friend who experienced black mold in their house and they didn't know it was behind walls and under the carpets...they started having health issues and after a long "what is going on w/us"...they discovered the mold. It was so bad at that point that they had to move out and the house was almost completely gutted in order to remedy the situation. They didn't see it...it got started in areas that they couldn't see.

Adding to the mix...when humidity is kept at a higher level it can also release more toxins into the air. Formaldehyde from building materials being just one of those toxins.

Healthcare professionals and home builders all say the same thing...the healthiest range for us and the health of our homes is between 45 and 55% (some say 40-50%), tops. You might not see the problems right away but sustained, high humidity can and will eventually create some problems.

[Manu]

Originally Posted by katrina

Pushing it to 60-70% on a consistent basis...even at those temps...could create problems, over time. Some viruses thrive at higher humidity (the flu!), as do dust mites, fungi, and molds/mildew. And, unfortunately, a lot can be going on behind walls that you can't see. By the time it becomes evident...the problem is huge. I had a friend who experienced black mold in their house and they didn't know it was behind walls and under the carpets...they started having health issues and after a long "what is going on w/us"...they discovered the mold. It was so bad at that point that they had to move out and the house was almost completely gutted in order to remedy the situation. They didn't see it...it got started in areas that they couldn't see.

Adding to the mix...when humidity is kept at a higher level it can also release more toxins into the air. Formaldehyde from building materials being just one of those toxins.


Healthcare professionals and home builders all say the same thing...the healthiest range for us and the health of our homes is between 45 and 55% (some say 40-50%), tops. You might not see the problems right away but sustained, high humidity can and will eventually create some problems.

I'm sorry but that is not simply not true... This is a misconception. Some climates have naturally that level of humidity year long. In my climate we have naturally 60% humidity and houses do not rot.. I'm not sure where you get this information from... please keep in mind humidity means nothing if you don't take into account other temperature and other factors...

[katrina]

Originally Posted by Manu

I'm sorry but that is not simply not true... This is a misconception. Some climates have naturally that level of humidity year long. In my climate we have naturally 60% humidity and houses do not rot.. I'm not sure where you get this information from... please keep in mind humidity means nothing if you don't take into account other temperature and other factors...

My information comes from reliable sources...a friend who is a home builder, one friend who is an HVAC person, and my allergy doctor. And, my friend who shared her very long and horrendous experience of black mold. As a matter of fact, a little googling will all provide the same parameters and information. Even when I try to find something that says 70% is OK...I can't find it. Anywhere.

Obviously, your house is your business and maybe...just maybe...your house has some aspects or special something where that level of humidity will not cause long term problems. However, the facts are the facts, and most newer homes w/a sustained level of 70% indoors...well, it could very well be a recipe for disaster.

On the flip side...low humidity also comes w/it's share of problems. Sinus issues, other illnesses thrive in low humidity, and wood problems from too little humidity. It's a balancing act and both home builder experts and healthcare professionals say the "sweet spot" is 45-55% (or 40-50%).

[Manu]

Just to clarify. The problem is NEVER humidity. The problem is CONDENSATION. If you can maintain 70% humidity and not have condensation you will not have mold, corrosion, etc issues.

Low humidity is brutal on homes... Wood shrinks under low humidity, causing walls and furniture to crack, floors to have gaps cracking of paint, the list is long.

When they give a figure of 45 50% that's probably at a 20C temperature. You should be able to maintain 60% without any issues if you have other conditions ok, and much higher if temperatures are a bit higher. Also, air circulation is key! If you have a couch that blocks air circulation to a cold wall, carpets to a cold floor, curtains to a cold window, all this will cause condensation which will cause mold and other issues. I hope this clarifies that!

---------- Post added at 07:36 AM ---------- Previous post was at 07:30 AM ----------

Also Katrina, you are sharing things based on your Ohio personal conditions and your friends story, like if this was science and facts that applied to everyone. If you google properly, you will find the right information, look for dew point charts. It should help understand how it works a bit.

[greenpassion]

Well let me chime in here. I now have two cool mist ultrasonic humidifiers going in a very large room and the humidity hovers around 50%. When I got up this morning it was 49%. I have three small fans and there's plenty of air circulation in this room. The temps are always between 67 + 69. So far so good!

[katrina]

Originally Posted by Manu

Just to clarify. The problem is NEVER humidity. The problem is CONDENSATION. If you can maintain 70% humidity and not have condensation you will not have mold, corrosion, etc issues.

Low humidity is brutal on homes... Wood shrinks under low humidity, causing walls and furniture to crack, floors to have gaps cracking of paint, the list is long.

When they give a figure of 45 50% that's probably at a 20C temperature. You should be able to maintain 60% without any issues if you have other conditions ok, and much higher if temperatures are a bit higher. Also, air circulation is key! If you have a couch that blocks air circulation to a cold wall, carpets to a cold floor, curtains to a cold window, all this will cause condensation which will cause mold and other issues. I hope this clarifies that!

---------- Post added at 07:36 AM ---------- Previous post was at 07:30 AM ----------

Also Katrina, you are sharing things based on your Ohio personal conditions and your friends story, like if this was science and facts that applied to everyone. If you google properly, you will find the right information, look for dew point charts. It should help understand how it works a bit.

These are not my opinions and my information is not for Ohio conditions only. My friend w/the mold issues lived in Baltimore, Maryland at the time and other folks with similar devastating problems have lived all over the US.

The information I shared is widely recognized and advised for all homeowners by many professionals. The US EPA advises humidity be maintained between 30 and 50%...the lower during the winter and the higher during the summer. I did a bit of googling and it turns out the Canadian gov't advises the same 30-50% as a healthy level for humans as well as structures. All recognized authorities state the same thing...consistently high humidity levels w/in a home can, eventually, result in not only health issues but structural problems.

So, no, these are not my opinions and they are not based solely on Ohio climate. The newer a home is and the more air tight the structure...it is even more important to heed this advice. Like I said, my friend's home was infested w/black mold and they never saw it...a lot can be going on behind the walls that most people can't see...until it's too late. So much w/in the building is porous...drywall, carpet, wood, insulation...and even though you can't see it...all of it is absorbing moisture even when the air feels dry.

Personally, I would never risk my house or the headache of a major remediation of mold in order to keep my orchids a little more comfortable during the winter. My humidity is typically in the 30-45% range during the day and goes up in the upper 50's+ during the night. On my big watering days the humidity will soar into the 60% range at night for a day or two...but then returns to the 50'. This is a range that is quite comfortable for me and, quite frankly, most orchids are OK w/that level, provided they are watered properly. I grow a wide variety of orchids and most never skip a beat w/these levels of humidity. Even the mounted plants. Admittedly, there are some orchids I can not grow due to my dry conditions...but I accept that because my house is priority over an orchid. If I ever get a g/h then I will consider those that perhaps need more humidity. In the meantime, I will stick w/what the professionals consider the ideal for the health of my home and if for some reason I started losing all my orchids (hasn't happened in almost 10 years!) then I will simply switch back to growing mostly cacti and succulents. Actually, I joke about that all the time because I would have far more time if I did grow only those in the cacti and succulent families because I would definitely cut back on the number of watering I would have to do in a month. Some of my cacti see water only once a month! Life would be easier, for sure.

Manu, I wholeheartedly disagree w/your statements and respectfully suggest that it is you who needs to do a bit more googling on this subject. I would really hate to see you in the situation that my friend had to deal with. I wouldn't wish what happened to her and her family on anyone...it was awful. Not just the health problems she and one of her kids experienced but also the financial difficulties they endured over the entire situation.

[Manu]

Katrina, it seems you did not take time to do your homework before commenting... Did you research dew point, relative vs absolute humidity. Etc?

---------- Post added at 09:29 AM ---------- Previous post was at 08:42 AM ----------

First, I do not maintain 70% humidity in my entire house, I maintain that amount in my growing area, naturally. A few feet away l, I measure 50 %. The plants transpire and the moist moss increases the humidity in the immediate vicinity of the plants.

Second, yes the government's will recommend 40-50% RH for your comfort. Those figures are provided as guidelines don't don't take in consideration other factors. They obviously won't recommend you maintain 70% in your house and neither do I.

Third, I suggested you research dew points, I will reiterate this. You need to understand how condensation occurs which is what can de damaging to structures. Also have a look at relative vs absolute humidity, another important concept you need to understand.

4th, this is not a home building/maintaining forum, we are here to discuss orchids and their growing conditions. Providing 70% would be beneficial for almost all orchids, some even much higher. The key is air circulstion with these level of humidity.

Also, without even performing any research, common sense dictates that you can have yearly 70% RH levels and not be sick or have dammage to buildings. Think of all the tropical climate countries on this planet and level of constant humidity they deal with. Humidity means nothing if you don't take in consideration the other surrondings factors.

What you are doing here is like saying that someone that weights 200 pounds is automatically overweight... Sure if you measure 5 feet and weight 200 pounds, you probably have a weight issue. But if you measure 6ft3 and weight 200 pounds you're probably in a heathly weight range. Then there are other factors, suchs as muscle %. I hope this image will help you take a step back and understand you need to take all factors in consideration.

Bottom line, you are spreading misinformation.

[Ray]

Manu, I think your are missing or ignoring Katrina's point.

It is well established throughout the world that maintaining an in-home relative humidity level at around 50% (+/-) is the best for the structure and its contents, animate and inanimate.

That is not to say that going away from that target is automatically going to be damaging or unhealthful, but it does increase the likelihood of an issue arising.

[Manu]

No no Ray, don't go there, I fully understood and clearly explained that, Not sure why you'd say that, please read above!!

---------- Post added at 11:44 AM ---------- Previous post was at 11:40 AM ----------

You can't look at relative humidity alone that was my point all along and I think I made it very clear in my last comment if it wasn't already clear, need to look at all factors, and I know for a fact that you very well know that being as smart and knowledgeable as you are :-)