Basements, Attics and Crawl Spaces - Crawlspace Mold and Encapsulation - Need advise.
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deadbolt67
10-28-09, 06:55 PM
I am new to the forum and need some advise. We have a home that is just over a year old and was new when purchased. This past summer we had a lot of rain and the weather was very humid.
About two months ago, I notice some hardwood in our dining room was cupping and thought "moisture". I opened the crawlspace and looked around the foundation of the home, but did not find any leaks, standing water, or any sign of water staining on the blocks. However, it was very humid in the crawlspace. The space does have a moisture barrier, but it was poorly installed with gaps between the sheets and it does not meet the walls in many places. Anyway, when I took a closer look at the joists and OSB, I noticed mildew and light green mold in patches throughout the entire crawlspace. I did some reading and decided to seal the foundation vents and add a standard home type dehumidifier and directed the drain hose about 15ft outside through the foundation drain. Since then, the humidity has dropped to about 55% avg throughout the space.
I have received three quotes on cleaning up the mold and mitigating it's return over the 1900 sq ft. of flooring.
Quote 1) Fog the entire space with moldicide, leave the existing cheap vapor barrier, cover the walls, and piers, with new 6mil plastic sealed in place with treated wood strips about 10 in. below the sill plate. Then, install new 12 mil plastic on the floor and cover all seams with tape to create a encapsulated space. Cost: $6750.00
Quote 2) Spray the entire floor with Bora Care w/ Mold care. Then, return a few days later, remove existing vapor barrier, cover the walls, and piers, with 6mil plastic (Clear) sealed in place with treated wood strips up to the sill plate. Then, install 10 mil plastic on the floor and join together with tape to create a encapsulated space. Finally, they want to add a Dry-Crawlspace Plus dehumidifier and install a new access door. Cost: $4600.00
Quote 3) Soda blast the entire floor space and joists to remove the mold, follow up with hydrogen peroxide solution sprayed on the floor space, remove the old vapor barrier, install a new 6 mil barrier on the floor (no walls, or tape, just overlap and bring up to the walls), install a SaniDry CSB dehumidifier and a new access door. Cost: $5250.00
Quote 1 is a local company that is not franchised and they offer a 3 yr warranty. Quote 2 is a larger nationwide franchise with a 10 yr warranty, but they indicated they don't normally tape all of the floor barrier seams, just enough to keep everything fastened. Quote 3 is a large franchise that sells high end encapsulation systems. However, the tech said he did not see a reason to install a system (no indication of any water just humidity) and recommended getting rid of the mold, install a dehumidifier and keep the vents sealed.
I know this is a long post, but I don't know which way to turn. I would really appreciate any insight from the fine folks on the forum. BTW, we are located in AL where the summers are very hot and humid.
THANKS!
About two months ago, I notice some hardwood in our dining room was cupping and thought "moisture". I opened the crawlspace and looked around the foundation of the home, but did not find any leaks, standing water, or any sign of water staining on the blocks. However, it was very humid in the crawlspace. The space does have a moisture barrier, but it was poorly installed with gaps between the sheets and it does not meet the walls in many places. Anyway, when I took a closer look at the joists and OSB, I noticed mildew and light green mold in patches throughout the entire crawlspace. I did some reading and decided to seal the foundation vents and add a standard home type dehumidifier and directed the drain hose about 15ft outside through the foundation drain. Since then, the humidity has dropped to about 55% avg throughout the space.
I have received three quotes on cleaning up the mold and mitigating it's return over the 1900 sq ft. of flooring.
Quote 1) Fog the entire space with moldicide, leave the existing cheap vapor barrier, cover the walls, and piers, with new 6mil plastic sealed in place with treated wood strips about 10 in. below the sill plate. Then, install new 12 mil plastic on the floor and cover all seams with tape to create a encapsulated space. Cost: $6750.00
Quote 2) Spray the entire floor with Bora Care w/ Mold care. Then, return a few days later, remove existing vapor barrier, cover the walls, and piers, with 6mil plastic (Clear) sealed in place with treated wood strips up to the sill plate. Then, install 10 mil plastic on the floor and join together with tape to create a encapsulated space. Finally, they want to add a Dry-Crawlspace Plus dehumidifier and install a new access door. Cost: $4600.00
Quote 3) Soda blast the entire floor space and joists to remove the mold, follow up with hydrogen peroxide solution sprayed on the floor space, remove the old vapor barrier, install a new 6 mil barrier on the floor (no walls, or tape, just overlap and bring up to the walls), install a SaniDry CSB dehumidifier and a new access door. Cost: $5250.00
Quote 1 is a local company that is not franchised and they offer a 3 yr warranty. Quote 2 is a larger nationwide franchise with a 10 yr warranty, but they indicated they don't normally tape all of the floor barrier seams, just enough to keep everything fastened. Quote 3 is a large franchise that sells high end encapsulation systems. However, the tech said he did not see a reason to install a system (no indication of any water just humidity) and recommended getting rid of the mold, install a dehumidifier and keep the vents sealed.
I know this is a long post, but I don't know which way to turn. I would really appreciate any insight from the fine folks on the forum. BTW, we are located in AL where the summers are very hot and humid.
THANKS!
airman.1994
10-28-09, 08:35 PM
Looks like most of the quotes are about the same. Let me tell you what I would do. 1st Closing the vents was a good idea. 2nd fogging the crawl space will not get enough chemical on to the wood. We use an airless sprayer. Make sure they use a chemical that is EPA approved for it's use. We use Foster 40-80. 3rd soda blasting or any kind of blasting is a very bad idea there are lots of studies saying this. The issue is it makes all the mold air borne and it could easily get into your home. 4th spray glue is much better way to seal the joints and VB to the wall because it will not come loose after a few years down the road. 5th If you are not storing any thing in the crawl 6mil VP will be fine on the floor. It will take some walking on and is stronger than you think. Also Id go with white thats what we use. You will be able to see so much better. What # am I on Oh 6th Say no to the dehumidifier at this time. Once you get everything installed you most likely will not need it. But I will say go to Radio Shack and get a remote RH sensor so you can see what it is with out going down there. 7th THIS IS THE MOST IMPORTANT PART OF THE JOB. NO MOLD REMEDIATION SHOULD BE DONE UNLESS THEY PUT THE CRAWL UNDER NEGATIVE PRESSURE. This goes back to #3 and making the mold air borne. This should be done which ever way you go.#8 did any of them try to sell you a antimicrobial coating to keep any mold from growing back. I highly recommend it. We use Foster 40-51 or 40-20.
Maybe I have my head in the clouds but I think we offer more for the money than your guys. And I have never had a crawl job over $4000 and your crawl is about the norm.
Maybe I have my head in the clouds but I think we offer more for the money than your guys. And I have never had a crawl job over $4000 and your crawl is about the norm.
ArmchairDIY
10-28-09, 08:41 PM
Our Climate here is very different from yours, and mold issues such as yours are something I do not see often. I'm going to assume someone with more specific expertise will answer shortly.
The one suggestion I will make is, contact the original builder. It appears to me proper measure were not taken to prevent moisture issues.
The one suggestion I will make is, contact the original builder. It appears to me proper measure were not taken to prevent moisture issues.
GBR in WA
10-28-09, 09:14 PM
If in a termite area don't seal the wall plastic to the sill plate or you won't see the bugger's towers.
Be safe, Gary
Be safe, Gary
deadbolt67
10-29-09, 04:27 PM
Looks like most of the quotes are about the same. Let me tell you what I would do. 1st Closing the vents was a good idea. 2nd fogging the crawl space will not get enough chemical on to the wood. We use an airless sprayer. Make sure they use a chemical that is EPA approved for it's use. We use Foster 40-80. 3rd soda blasting or any kind of blasting is a very bad idea there are lots of studies saying this. The issue is it makes all the mold air borne and it could easily get into your home. 4th spray glue is much better way to seal the joints and VB to the wall because it will not come loose after a few years down the road. 5th If you are not storing any thing in the crawl 6mil VP will be fine on the floor. It will take some walking on and is stronger than you think. Also Id go with white thats what we use. You will be able to see so much better. What # am I on Oh 6th Say no to the dehumidifier at this time. Once you get everything installed you most likely will not need it. But I will say go to Radio Shack and get a remote RH sensor so you can see what it is with out going down there. 7th THIS IS THE MOST IMPORTANT PART OF THE JOB. NO MOLD REMEDIATION SHOULD BE DONE UNLESS THEY PUT THE CRAWL UNDER NEGATIVE PRESSURE. This goes back to #3 and making the mold air borne. This should be done which ever way you go.#8 did any of them try to sell you a antimicrobial coating to keep any mold from growing back. I highly recommend it. We use Foster 40-51 or 40-20.
Maybe I have my head in the clouds but I think we offer more for the money than your guys. And I have never had a crawl job over $4000 and your crawl is about the norm.
Thank you for the advise.
The first two companies did not mention negative pressure, but the third (soda blasting), said the space would be negatively pressured to prevent blasted mold from entering the house. I don't remember what secondary product they were going to use but do remember it had a hydrogen peroxide component.
I am going to try and find some other companies offering similar services in this area. We are not too far from Nashville and I am sure there are plenty in that area.
Regarding ArmchairDIY, I spoke with the guy who inspected my home last year. He said the codes only mention having the ability to remove water from the foundation (I have a drain system in the crawl) and ventilation. He doubted that I would have any luck trying to go back on the builder.
Thanks!
Maybe I have my head in the clouds but I think we offer more for the money than your guys. And I have never had a crawl job over $4000 and your crawl is about the norm.
Thank you for the advise.
The first two companies did not mention negative pressure, but the third (soda blasting), said the space would be negatively pressured to prevent blasted mold from entering the house. I don't remember what secondary product they were going to use but do remember it had a hydrogen peroxide component.
I am going to try and find some other companies offering similar services in this area. We are not too far from Nashville and I am sure there are plenty in that area.
Regarding ArmchairDIY, I spoke with the guy who inspected my home last year. He said the codes only mention having the ability to remove water from the foundation (I have a drain system in the crawl) and ventilation. He doubted that I would have any luck trying to go back on the builder.
Thanks!
crawlspacemd
11-06-09, 09:41 AM
Deadbolt67,
Sealing the vents is a good first step. The key to successful crawlspace repair is to permenantly stop the stream of moisture into the rest of the house. The CleanSpace Encapsulation System is the only system designed to handle ground moisture, and moisture from a plumbing leak, with SmartSump and to bring the relative humidity to a point where mold can no longer grow, with the SaniDry CSB.
Whether you are looking to stay in your house for only a few years or forever, the CleanSpace Encapsulation System will pay for itself over time. Having seen the results of thousands of successful installations, I can attest to the fact that CleanSpace is a solution, others are merely band-aids to a future problem.
Sealing the vents is a good first step. The key to successful crawlspace repair is to permenantly stop the stream of moisture into the rest of the house. The CleanSpace Encapsulation System is the only system designed to handle ground moisture, and moisture from a plumbing leak, with SmartSump and to bring the relative humidity to a point where mold can no longer grow, with the SaniDry CSB.
Whether you are looking to stay in your house for only a few years or forever, the CleanSpace Encapsulation System will pay for itself over time. Having seen the results of thousands of successful installations, I can attest to the fact that CleanSpace is a solution, others are merely band-aids to a future problem.
airman.1994
11-06-09, 05:34 PM
Deadbolt67,
Sealing the vents is a good first step. The key to successful crawlspace repair is to permenantly stop the stream of moisture into the rest of the house. The CleanSpace Encapsulation System is the only system designed to handle ground moisture, and moisture from a plumbing leak, with SmartSump and to bring the relative humidity to a point where mold can no longer grow, with the SaniDry CSB.
Whether you are looking to stay in your house for only a few years or forever, the CleanSpace Encapsulation System will pay for itself over time. Having seen the results of thousands of successful installations, I can attest to the fact that CleanSpace is a solution, others are merely band-aids to a future problem.
Id say know real difference between them.
A sealed crawl is a sealed crawl.
Sealing the vents is a good first step. The key to successful crawlspace repair is to permenantly stop the stream of moisture into the rest of the house. The CleanSpace Encapsulation System is the only system designed to handle ground moisture, and moisture from a plumbing leak, with SmartSump and to bring the relative humidity to a point where mold can no longer grow, with the SaniDry CSB.
Whether you are looking to stay in your house for only a few years or forever, the CleanSpace Encapsulation System will pay for itself over time. Having seen the results of thousands of successful installations, I can attest to the fact that CleanSpace is a solution, others are merely band-aids to a future problem.
Id say know real difference between them.
A sealed crawl is a sealed crawl.