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quentin Posted: Nov 14, 2006 05:30 PM	Mold problems? I've been trying to see if there is even a market for foam here since I am looking at getting in to it and talking with a local contractor he said it has a great R value but it doesn't let the house "breath". As a result he said he required a waiver on the one house he has used it on and within a month the basement was growing mold up the walls. They solved it with a couple of dehumidifiers running all out for almost a year but he is scared to really do anything with it now. I figured it was most likely due to using .5lb foam and moisture already in the basement causing the problem. We have a pretty high water table in a lot of areas around here and I am worried it may be a problem or the experience other contractors have had making any market about dead for me. Any ideas and am I guessing the most likely causes?
Gerry Wagoner Posted: Nov 18, 2006 09:24 PM	Yep. Install an HRV to solve the problems. Foamed houses need one automatically. olger
quentin Posted: Nov 18, 2006 10:23 PM	Ahhh, ok. Now I know what to tell them so they don't have a fit about that problem. No idea about any of this so doing all the research to see if I can get a market and start up a company in this area.
Gerry Wagoner Posted: Nov 19, 2006 08:48 PM	I understand Quentin. Where are you located? I'm in Ohio.
quentin Posted: Nov 19, 2006 09:08 PM	I'm in the Dayton area. If I can find anyone doing it that I can tail for a couple of days and maybe help out I might do that too. One of my wife's big worries is that I am a disable Marine and with a bad shoulder she is worried if I could handle the work even. If you happen to be doing any work within about an hour of here and wouldn't mind someone doing a tag along I'd love the chance!
Aaron Scurlock Posted: Nov 20, 2006 09:06 AM	Umm, I hate looking stoo-ped, but what is an HRV? I am going to do my sister's house with 2#. I will need to know all there is to know. I have only been spraying polyureas so far. What is the yeild on a 2# set?
Melvin Chandler Posted: Nov 20, 2006 10:55 AM	A.B. HRV is basically a return/fresh air ventilation system. The HRV is used in northern climates where the outside air (cold) can be heated when pulled into the house. That's the best way to ensure you are moving air properly into and through the house. The other option is to stick a 3-4" pipe out a wall with a bug cap on it and tie it into the return air trunk. That will pull fresh air in and may pressurize the house a bit but more than likely you'll have plenty of places for the pressure to excape (range hoods, chimneys, doors, pipes in walls, windows, etc)
quentin Posted: Nov 20, 2006 10:56 AM	I had to look it up too and that GOD for Google anymore! LOL http://www.toolbase.org/Technology-Inventory/HVAC/energy-recovery-ventilators HRV is Heat Recovery Ventilator which is a heat exchanger for venting air in and outside of a house without loss of cooling or heating of the interior air. Looking they are about 80% efficient.
quentin Posted: Nov 20, 2006 10:57 AM	Double posted by accident.
Aaron Scurlock Posted: Nov 20, 2006 11:57 AM	I forgot to mention maximium passes. Anways, might it not be a good idea to insulate the ypstairs addition with closed cellif they do not have the heat exchange thingy? The rest of the existing house is cellulose and fiberglass combo.
Gerry Wagoner Posted: Nov 20, 2006 09:41 PM	Spray foam the upstairs and consider having a blower door test after completion. The local utility company should offer the test. Anything below .2 is too tight. Anything above .2 is too sloppy. This is olger signing off..
Aaron Scurlock Posted: Nov 20, 2006 10:26 PM	Dammit, man, I am a roofer. :) What is the blower door test all about?
Melvin Chandler Posted: Nov 20, 2006 11:03 PM	I reckon they take this blower and put it in a door or entrance area. Crank up the fan and calculate what the air exchange rate will be based on how much air infiltration/leaks there may be in the area tested.
Dave Strnad Posted: Nov 21, 2006 10:27 AM	Ok I'm still not convinced on the mold issue. If the SPF is applied to the proper thickness then it's my understanding that there will be no condinsation on it. If there is no liquid water there can be no mold. Right? Hvac code requires a 4" fresh air piped into the return, I was told that this still is not adaquate, and that a HRV is still needed. Obviously we are all from different areas, but is the 4" fresh air enough or should an HRV always be used?
quentin Posted: Nov 21, 2006 10:37 AM	My understanding is that humidity in the house is the culprit on this and they solved the issue with dehumidifiers. While this might be needed in the summer which actually helps with keeping the house more comfortable, I don't think anything like that would be needed in the winter unless they saw serious condensation on the windows. It may be a case where the basement floor wasn't sealed properly too allowing moisture to seep in through the cement in the foundation that way.

Author

Comments

quentin

Posted: Nov 14, 2006 05:30 PM

Mold problems?

I've been trying to see if there is even a market for foam here since I am looking at getting in to it and talking with a local contractor he said it has a great R value but it doesn't let the house "breath". As a result he said he required a waiver on the one house he has used it on and within a month the basement was growing mold up the walls.

They solved it with a couple of dehumidifiers running all out for almost a year but he is scared to really do anything with it now.

I figured it was most likely due to using .5lb foam and moisture already in the basement causing the problem.

We have a pretty high water table in a lot of areas around here and I am worried it may be a problem or the experience other contractors have had making any market about dead for me. Any ideas and am I guessing the most likely causes?

Gerry Wagoner

Posted: Nov 18, 2006 09:24 PM

Yep. Install an HRV to solve the problems. Foamed houses need one automatically.

olger

quentin

Posted: Nov 18, 2006 10:23 PM

Ahhh, ok. Now I know what to tell them so they don't have a fit about that problem. No idea about any of this so doing all the research to see if I can get a market and start up a company in this area.

Gerry Wagoner

Posted: Nov 19, 2006 08:48 PM

I understand Quentin. Where are you located? I'm in Ohio.

quentin

Posted: Nov 19, 2006 09:08 PM

I'm in the Dayton area. If I can find anyone doing it that I can tail for a couple of days and maybe help out I might do that too. One of my wife's big worries is that I am a disable Marine and with a bad shoulder she is worried if I could handle the work even.

If you happen to be doing any work within about an hour of here and wouldn't mind someone doing a tag along I'd love the chance!

Aaron Scurlock

Posted: Nov 20, 2006 09:06 AM

Umm, I hate looking stoo-ped, but what is an HRV?

I am going to do my sister's house with 2#. I will need to know all there is to know. I have only been spraying polyureas so far.

What is the yeild on a 2# set?

Melvin Chandler

Posted: Nov 20, 2006 10:55 AM

A.B.
HRV is basically a return/fresh air ventilation system. The HRV is used in northern climates where the outside air (cold) can be heated when pulled into the house. That's the best way to ensure you are moving air properly into and through the house. The other option is to stick a 3-4" pipe out a wall with a bug cap on it and tie it into the return air trunk. That will pull fresh air in and may pressurize the house a bit but more than likely you'll have plenty of places for the pressure to excape (range hoods, chimneys, doors, pipes in walls, windows, etc)

quentin

Posted: Nov 20, 2006 10:56 AM

I had to look it up too and that GOD for Google anymore! LOL

http://www.toolbase.org/Technology-Inventory/HVAC/energy-recovery-ventilators

HRV is Heat Recovery Ventilator which is a heat exchanger for venting air in and outside of a house without loss of cooling or heating of the interior air. Looking they are about 80% efficient.

quentin

Posted: Nov 20, 2006 10:57 AM

Double posted by accident.

Aaron Scurlock

Posted: Nov 20, 2006 11:57 AM

I forgot to mention maximium passes.

Anways, might it not be a good idea to insulate the ypstairs addition with closed cellif they do not have the heat exchange thingy? The rest of the existing house is cellulose and fiberglass combo.

Gerry Wagoner

Posted: Nov 20, 2006 09:41 PM

Spray foam the upstairs and consider having a blower door test after completion. The local utility company should offer the test. Anything below .2 is too tight. Anything above .2 is too sloppy.

This is olger signing off..

Aaron Scurlock

Posted: Nov 20, 2006 10:26 PM

Dammit, man, I am a roofer. :)

What is the blower door test all about?

Melvin Chandler

Posted: Nov 20, 2006 11:03 PM

I reckon they take this blower and put it in a door or entrance area. Crank up the fan and calculate what the air exchange rate will be based on how much air infiltration/leaks there may be in the area tested.

Dave Strnad

Posted: Nov 21, 2006 10:27 AM

Ok I'm still not convinced on the mold issue. If the SPF is applied to the proper thickness then it's my understanding that there will be no condinsation on it. If there is no liquid water there can be no mold. Right? Hvac code requires a 4" fresh air piped into the return, I was told that this still is not adaquate, and that a HRV is still needed. Obviously we are all from different areas, but is the 4" fresh air enough or should an HRV always be used?

quentin

Posted: Nov 21, 2006 10:37 AM

My understanding is that humidity in the house is the culprit on this and they solved the issue with dehumidifiers. While this might be needed in the summer which actually helps with keeping the house more comfortable, I don't think anything like that would be needed in the winter unless they saw serious condensation on the windows. It may be a case where the basement floor wasn't sealed properly too allowing moisture to seep in through the cement in the foundation that way.

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