Crawl Space Remediation - Humidity Control - Non Valkyrie Related

[carolinarider09]

When I built the house, I washed a lot of TV about home building, took the course to become a "contractor" and read what I could.  One of the programs I watched was Holmes on Homes.  It's why I have an instant on gas water heater, the lighting system we have and the "Fresh Water Manifold". 

I think he also discussed things having to do with sealing the crawl space and humidity control.  I opted out of doing that but did try and include some humidity control.  My system, some fans, was a failure. 

I also put down the required plastic barrier on the crawlspace "dirt".  I had the same thing done (don't remember why) at our previous home. I had an issue with it because the "plastic" barrier was always damp.  (I know why now )

So, we had this "black mold" event.  First step, install a sump pump in the crawl space.  Next step seal the crawl space.   That was done this week.  And the fourth step, install a dehumidifier. 

The dehumidifier has been up and running for about 48 hours now and the carrell space has been totally sealed (well there is one door that needs some work but its only a small opening) and a plastic liner has been installed. )Oh I did put down a plastic barrier when I was building the house but put a little sand over the plastic so there would be no standing water.)

I have been monitoring the temperature and humidity in the crawl space since June.  In July, July, and August, the humidity was 98% to 99% and the temperature was in the mid 70's.   

As outside temperature dropped in September and now October, the temperature dropped to the low 70's to upper 60's.  Humidity was around 85%, depending on outside stuff.

Now are having the dehumidifier up and running for about 48 hours, and with outside temps ranging from low 40's to mid 70's the crawl space temperature is fairly stable at 67 degrees and the humidity is stable at about 67%.   I credit the dehumidifier with the drop on humidity.  But.... outside humidity has been in the 80's.  The sensor in the crawlspace is on the other side of the dehumidifier. 

Only time will tell about the whole project.  Next task, remove the ceiling black mold.   Will have to have someone else do it.  Not a job I can tackle. 

Here is what the crawl space and dehumidifier look like.





The small device in the front is a "condensate" pump to remove the water the dehumidifier removes from the air to the outside.  Did have to drill another hole for the discharge. 
 

[Jess from VA]

Nothing I like more than crawling around under a house with high heat and humidity and black mold.

Any bugs, bees or snakes under there?   

Those are some monster stringers.

Perfect place for a mother-in-law suite.   

[carolinarider09]

No bees, no snakes, just a few bugs that were just "bugs"   

[_Sheffjs_]

Well somewhat new to WNC with a new build, I am interested in this very topic.   

[98valk]

with a sealed up, encapsulated crawl space, your duct work should not be insulated and sealed. just normal leakage of duct joints is usually enough for good air transfer in the crawl space.
This is how I have my crawl space and for a rental house I use to own.

https://crawlspacerepair.com/blog/crawl-space-foundation-vents-can-you-really-seal-them-up/

[sidecarwilliam]

Black mold dies just like any other mold, Bleach (10%) and can be kept away with continued dehumidification with warm dry air and a dehumidifier. Antibacterial paint helps and it is all DIY if you are one of the lucky ones like me, no reaction to mold.
Spent 10 years as an Industrial Hygienist chasing mold and other things .

bill.

[carolinarider09]

with a sealed up, encapsulated crawl space, your duct work should not be insulated and sealed. just normal leakage of duct joints is usually enough for good air transfer in the crawl space.
This is how I have my crawl space and for a rental house I use to own.

https://crawlspacerepair.com/blog/crawl-space-foundation-vents-can-you-really-seal-them-up/

I will give that a look.  Thanks.

[carolinarider09]

Black mold dies just like any other mold, Bleach (10%) and can be kept away with continued dehumidification with warm dry air and a dehumidifier. Antibacterial paint helps and it is all DIY if you are one of the lucky ones like me, no reaction to mold.
Spent 10 years as an Industrial Hygienist chasing mold and other things .

bill.

Bill, thanks for the information.  Two issues in my case.  One, its at the very top of the ceiling, about 20 feet up and while I have a scaffold I used to put up the ceiling boards I don't want to put it back up now that the house is "finished".   Two, I am older now and I don't think I want to use an "extended" device but, could be persuaded. 

If you do not mind, I might send you some questions via "messenger" on here for some specific feedaback. 

The mold is the black spot in the center of the image on the white (drywall) material. 

[carolinarider09]

Well somewhat new to WNC with a new build, I am interested in this very topic.   

Any questions, just ask. 

I did my best to study and learn and find things out before I started my build.  I did all the work except for the plumbing (waste and water, was not real sure on the use of PEX tubing), HVAC install (although I got the CERT), and drywall.  Oh, I forgot, I did not do the foundation pillars or curtain wall but I did pour (with the help of a friend) the footer. 

[Jersey mike]

Now that the crawl space is nice and clean looking keep an eye out for rodent droppings and get rid of them as quickly as possible. Also check your condensation pump every once in a while to be sure bugs and dust aren’t accumulating in there, it could be considered a water source for undesirable pests.

[Oss]

we have the simplesafe alarm set up in our home
wireless
they have tiny sensors that detect water
they work
had one under the kitchen sink and it let me know when something bad happened...loudly  lol

so we have a similar pump that takes the condensate out for humidifier/ac unit in my basement

I took a plastic container  maybe 14 x 20 x 4 and the pump is sitting IN the clear container with a sensor in it    Someday the pump will fail, the sensor will alert me and disaster avoided again if I am home

Just change the little battery yearly, I use rechargeable batteries I can use either the solar or regular charger  to keep fresh supplies

nice clean install Jim  

Oss

Now that I think about it I should order another to put under the hot water heater

[Jess from VA]

One, its at the very top of the ceiling, about 20 feet up and while I have a scaffold I used to put up the ceiling boards I don't want to put it back up now that the house is "finished".   Two, I am older now and I don't think I want to use an "extended" device but, could be persuaded. 

I have one of these fairly lightweight aluminum telescoping extension poles, that might reach your problem, from that balcony.  https://www.amazon.com/Unger-Professional-Connect-Clean-Telescopic/dp/B004S8XIE0/ref=asc_df_B004S8XIE0/?tag=hyprod-20&linkCode=df0&hvadid=312188616697&hvpos=&hvnetw=g&hvrand=4339953411624887371&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9008188&hvtargid=pla-522782619299&psc=1&tag=&ref=&adgrpid=62456414592&hvpone=&hvptwo=&hvadid=312188616697&hvpos=&hvnetw=g&hvrand=4339953411624887371&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9008188&hvtargid=pla-522782619299

The other (crazy) idea I had was to use one of those Super Soaker long range squirt gun rifles with a mild bleach and water solution, also from the balcony.  The mild bleach mix should not damage anything oversprayed.  It might need a few applications (with no scrubbing).  This thing goes up to 40 feet, and with a 24"bbl, accuracy is supposed to be good.  https://www.amazon.com/Stream-Machine-QF-2000-35-Inch-Launcher/dp/B000F32SM0/ref=asc_df_B000F32SM0/?tag=hyprod-20&linkCode=df0&hvadid=312163510212&hvpos=&hvnetw=g&hvrand=9842452167658204730&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9008188&hvtargid=pla-442421980541&th=1

[carolinarider09]

Now that the crawl space is nice and clean looking keep an eye out for rodent droppings and get rid of them as quickly as possible. Also check your condensation pump every once in a while to be sure bugs and dust aren’t accumulating in there, it could be considered a water source for undesirable pests.

I do keep track of the condensate pump for the HVAC unit will do the same for the dehumidifier.

[carolinarider09]

we have the simplesafe alarm set up in our home
wireless
they have tiny sensors that detect water
they work

Thanks.  I installed the security system in our house and there are two water sensors.  One in the room with the whole house "filter" and one behind the washing machine.  I have never tested them.  Guess I should

[carolinarider09]

Jess, regarding your two options. 

The first one I have considered and might well do but the wife was telling me that "chemicals" needed are not good for human consumption.  And yes I do have a face shield I could use... Still the other part of the issue is the floor underneath is hardwood.  It can be protected with some plastic but...... 

Regarding the second suggest, probably not but I also sort of considered it but, again, would require some "stuff" on the floor to catch the "extra" "overflow" stuff. 

[t-man403]

If you find that the work you have done is not doing what you expected then you may want to consider an HRV. That is the route that I would’ve taken in a situation like yours. Not sure what your outdoor humidity levels are, but the HRV will exchange air from outside to in without losing your indoor energy, but will exhaust the humidity and bring in outside dry air. Also helps with radon mediation which seems to be a huge concern nowadays, at least here. You would need just a small unit no more than 150 CFM.

[98valk]

If you find that the work you have done is not doing what you expected then you may want to consider an HRV. That is the route that I would’ve taken in a situation like yours. Not sure what your outdoor humidity levels are, but the HRV will exchange air from outside to in without losing your indoor energy, but will exhaust the humidity and bring in outside dry air. Also helps with radon mediation which seems to be a huge concern nowadays, at least here. You would need just a small unit no more than 150 CFM.

 

[Jersey mike]

Many homes in our area which have crawl spaces are built with vents (appx 12 x on both ends and front and rear of the foundation block work allowing air to circulate, not sure if your home has that or if so, what will it do to the run time of your dehumidifier.

I’ve know people who have equipped the crawl space with attic fans near the vents to exhaust the air down there quicker than natural air flow provides.

[carolinarider09]

If you find that the work you have done is not doing what you expected then you may want to consider an HRV. That is the route that I would’ve taken in a situation like yours. Not sure what your outdoor humidity levels are, but the HRV will exchange air from outside to in without losing your indoor energy, but will exhaust the humidity and bring in outside dry air. Also helps with radon mediation which seems to be a huge concern nowadays, at least here. You would need just a small unit no more than 150 CFM.

When we built the house, and watch some stuff on TV (like Holmes on Homes ). I saw that.  I added two four inch ventilation pipes on the back porch roof but never connected them.

Mentally I had an issue with the "regeneration" (may not be the correct word) but if I wanted to bring in fresh dry air, the only way to do it would be to dry it and then cool it (drying generally adds heat) and then I would also have to add an exhaust system.

The two four inch intakes were my basic start and supplying fresh air since each bathroom has a "exhaust" fan.  And, if the house is well sealed then the exhaust fan actually draws a vacuum on the house and the air coming in may not be what you want.  However, I never got to the point were I could mentally accept the fresh air coming in as clean without having to "clean it and filter it"..... So, The pipes are there but not connected to anything.

Have thought of it several times over the past few months, (because of the mold and health also).  But....

[carolinarider09]

Many homes in our area which have crawl spaces are built with vents (appx 12 x on both ends and front and rear of the foundation block work allowing air to circulate, not sure if your home has that or if so, what will it do to the run time of your dehumidifier.

I’ve know people who have equipped the crawl space with attic fans near the vents to exhaust the air down there quicker than natural air flow provides.

I have two "exhaust fans" installed on two of the foundation wall vents that were set to control humidity.  I ran them for a while but no success.   

What I summarized was that if I was going to try and control the temp and humidity of the crawl space I would need some way to use air that was not at 80% humidity at 90 degrees.   Fresh air is a boon but..... it brings with it other issues. 

It can be filtered and heated, cooled or..... but that all takes money and "stuff".  So, I settled, for now, on the crawl space humidity thing.  I may well try and re-start my external air input and discharge system for the house but.. right now, that's just a thought.

[scooperhsd]

If you find that the work you have done is not doing what you expected then you may want to consider an HRV. That is the route that I would’ve taken in a situation like yours. Not sure what your outdoor humidity levels are, but the HRV will exchange air from outside to in without losing your indoor energy, but will exhaust the humidity and bring in outside dry air. Also helps with radon mediation which seems to be a huge concern nowadays, at least here. You would need just a small unit no more than 150 CFM.

South Carolina in the summer (not to mention spring and fall about a month each bordering summer) is pretty humid - heck, KC is humid during the summers.

[Rams]

Black mold dies just like any other mold, Bleach (10%) and can be kept away with continued dehumidification with warm dry air and a dehumidifier. Antibacterial paint helps and it is all DIY if you are one of the lucky ones like me, no reaction to mold.
Spent 10 years as an Industrial Hygienist chasing mold and other things .

bill.

The man knows of what he speaks.

I had a similar problem in a crawl space years ago.   I did install a sump pump for heavy rainy periods but, at the time really couldn't afford the dehumidifier.   So, using the a couple of vent openings in the block stem wall, I installed two exhaust fans to keep air moving down there.  Those fans were wired into the crawl space lighting switch which was easily reached.   Worked for me, mold wasn't seen again down there.

Rams

[f6john]

My solution has been a full basement with full HVAC control, problems solved. It does bring up another issue, two much house for two people and the corresponding higher cost for insurance, taxes and maintenance and the list goes on.

[Robert]

You did a great job on the crawl space 

[t-man403]

If you find that the work you have done is not doing what you expected then you may want to consider an HRV. That is the route that I would’ve taken in a situation like yours. Not sure what your outdoor humidity levels are, but the HRV will exchange air from outside to in without losing your indoor energy, but will exhaust the humidity and bring in outside dry air. Also helps with radon mediation which seems to be a huge concern nowadays, at least here. You would need just a small unit no more than 150 CFM.

When we built the house, and watch some stuff on TV (like Holmes on Homes ). I saw that.  I added two four inch ventilation pipes on the back porch roof but never connected them.

Mentally I had an issue with the "regeneration" (may not be the correct word) but if I wanted to bring in fresh dry air, the only way to do it would be to dry it and then cool it (drying generally adds heat) and then I would also have to add an exhaust system.

The two four inch intakes were my basic start and supplying fresh air since each bathroom has a "exhaust" fan.  And, if the house is well sealed then the exhaust fan actually draws a vacuum on the house and the air coming in may not be what you want.  However, I never got to the point were I could mentally accept the fresh air coming in as clean without having to "clean it and filter it"..... So, The pipes are there but not connected to anything.

Have thought of it several times over the past few months, (because of the mold and health also).  But....

For what it’s worth, I still would’ve gone with an HRV. The HRV filters the air before it enters your home. Even the air exiting your home is filtered through it. The filtration is done to keep the heat exchanger/core clean. I’ve installed many of these units and in some cases in much higher humidity than you have in your home i.e. indoor swimming pools.
The more you seal up your home, the more humid it’s going to be. The HRV acts as the open window and allows your home to breathe, without losing your energy dollar. To get rid of the humidity you need to cool the air, not heat it. The warmer the air, the more humidity it holds.
I always pressurize the home by bringing in more air than I am exhausting. That helps with negative pressure in the case of bath fans, dryers and central vacuum systems are running. So, if I’m exhausting 100 CFM, I will supply 110 CFM to replace it, just for numbers sake. The jist of what I’m saying is, you would not believe the difference in air quality in a home simply by moving air. If folks knew the contaminates in the air in their homes, just from the materials we build with alone, everyone would install an HRV! Having said that, I don’t have an HRV in my home  , but to make up for it, my furnace blower is on 24/7 and I draw in outdoor air via the duct system, full time no matter the season. Yes, I lose some of my heating dollar in the winter but at least the house isn’t stale and the temperature is consistent throughout the house.
Anyway, I think what you have done there is definitely going to help and what I am saying is just another route that could’ve been taken.

[carolinarider09]

t-man403:

Got it.  We are looking at the issue and seeing what might be done.  Not today but, maybe tomorrow. 

Thanks for the feedback.

[carolinarider09]

Just wanted to note that today, the system/device I have that is monitoring the crawlspace humidity and temperature, reached the reported set point for my newly installed Santa Fe dehumidifier which was 55%. 

It has been trending down since installation but 55% was the goal.  Will keep monitoring as outside gets cooler and dryer and we finally get some rain.  That, the rain, might well make a difference.