I have a 50 year old house with a crawlspace. I have hardwood floors and they are uninsulated underneath the house. Would it really make a difference to put insulation between the floor joists? I feel like I am losing alot of heat and air through my floors.
Thanks!
Well, I'm no heating and air expert, and I don't know didley squat about floors. However, I know heat rises. So unless your floor is where your roof should be, I'm guessing you're OK.
You might get the same benefit from making sure your crawl space is really tight.
Actually I think you will benefit from insulating your conventional floors. Use a vapor barrier batt and a batt support system when you do it. The batt supports will keep the batts snug against the floor and prevent them falling away.
They also say that insulating the walls of the crawlspace will help with keeping the floors warm during the winter months.
(02-02-2010 01:42 PM)BinghamptonNed Wrote: [ -> ]You might get the same benefit from making sure your crawl space is really tight.
This is your answer in a nutshell. In my business we remove insulation from crawlspaces very frequently. Too often it becomes moist, falls down, becomes a haven for rodents, and either does not allow your wood floors the moisture content that they need, OR traps too much moisture between the insulation and wood substructure causing wood destroying fungi to grow. Button up the crawlspace and make sure you have adequate ventilation, a great vent is one that opens and closes with the outdoor temp automatically (most people do not open and close their vents manually but your crawlspace needs the ventilation). Also, ensure that you have at least 80% of the crawlspace covered by at least a 6 mil poly vapor barrier so that any ground moisture that does rise will be trapped and dissipated with the proper ventilation above.
Putting insulation under floors that have not had it for 50 years will dramatically alter the moisture content of the wood. Whether it creates too much or alleviates what is there, warping of the wood will occur. As mentioned above, unless you have cracks in the floor, heat rises, and the chances of your home "losing" heat through the floors would be unlikely. Now, if there are cracks, etc., they could be drafty at foot level so I would make sure they are snug as well.
(02-02-2010 09:22 PM)Chi-Town Wrote: [ -> ] (02-02-2010 01:42 PM)BinghamptonNed Wrote: [ -> ]You might get the same benefit from making sure your crawl space is really tight.
This is your answer in a nutshell. In my business we remove insulation from crawlspaces very frequently. Too often it becomes moist, falls down, becomes a haven for rodents, and either does not allow your wood floors the moisture content that they need, OR traps too much moisture between the insulation and wood substructure causing wood destroying fungi to grow. Button up the crawlspace and make sure you have adequate ventilation, a great vent is one that opens and closes with the outdoor temp automatically (most people do not open and close their vents manually but your crawlspace needs the ventilation). Also, ensure that you have at least 80% of the crawlspace covered by at least a 6 mil poly vapor barrier so that any ground moisture that does rise will be trapped and dissipated with the proper ventilation above.
Putting insulation under floors that have not had it for 50 years will dramatically alter the moisture content of the wood. Whether it creates too much or alleviates what is there, warping of the wood will occur. As mentioned above, unless you have cracks in the floor, heat rises, and the chances of your home "losing" heat through the floors would be unlikely. Now, if there are cracks, etc., they could be drafty at foot level so I would make sure they are snug as well.
All that makes perfect sense.
I stand corrected.
(02-02-2010 09:22 PM)Chi-Town Wrote: [ -> ] (02-02-2010 01:42 PM)BinghamptonNed Wrote: [ -> ]You might get the same benefit from making sure your crawl space is really tight.
This is your answer in a nutshell. In my business we remove insulation from crawlspaces very frequently. Too often it becomes moist, falls down, becomes a haven for rodents, and either does not allow your wood floors the moisture content that they need, OR traps too much moisture between the insulation and wood substructure causing wood destroying fungi to grow. Button up the crawlspace and make sure you have adequate ventilation, a great vent is one that opens and closes with the outdoor temp automatically (most people do not open and close their vents manually but your crawlspace needs the ventilation). Also, ensure that you have at least 80% of the crawlspace covered by at least a 6 mil poly vapor barrier so that any ground moisture that does rise will be trapped and dissipated with the proper ventilation above.
Putting insulation under floors that have not had it for 50 years will dramatically alter the moisture content of the wood. Whether it creates too much or alleviates what is there, warping of the wood will occur. As mentioned above, unless you have cracks in the floor, heat rises, and the chances of your home "losing" heat through the floors would be unlikely. Now, if there are cracks, etc., they could be drafty at foot level so I would make sure they are snug as well.
Hey Chi-Town, serious crawl space question - do you have any experience with the newer system that gets installed under your house where they actually pull up your existing vapor barrier and put down a coating that is similar to swimming pool bottom? I had a guy quote me a few weeks ago and I'm not sure if it's worth the $$$. PM if you have any advice. Thanks.
From the research I have done on the internet, it seems their are varying opinions on crawlspace, ventilation, insulation, etc.
I understand the moisture problem that can exist in a crawlspace. Having at least a 6mil vapor barrier covering the entire dirt floor under that house is a must. I was just curious what alot of people do.
When I bought my house, I found wooden covers with insulation on the inside to cover up the crawlspace vents in the winter. The previous owner apparently made them. So right now, my crawlspace is covered up and not vented, except for a small hole near the access door. I'll remove the covers in the spring.
So I take it most people in Memphis with an older home DO NOT insulate the floors because of moisture and mold problems. I can see how that could be an issue. I know for a fact that I have moisture problems because my vapor barrier looks like a cheap plastic drop cloth you buy to cover furniture when painting. It's really thin. I plan to get under there this spring and put down a 6mil vapor barrier. (It's an adventure to get under a 50+ year old house to say the least!)
Chi....I don't understand what you mean when you say "button up your crawlspace but provide ventilation". Button up as in cover all the vents in the winter? Thanks!
(02-03-2010 04:02 PM)Watauga9 Wrote: [ -> ]From the research I have done on the internet, it seems their are varying opinions on crawlspace, ventilation, insulation, etc.
I understand the moisture problem that can exist in a crawlspace. Having at least a 6mil vapor barrier covering the entire dirt floor under that house is a must. I was just curious what alot of people do.
When I bought my house, I found wooden covers with insulation on the inside to cover up the crawlspace vents in the winter. The previous owner apparently made them. So right now, my crawlspace is covered up and not vented, except for a small hole near the access door. I'll remove the covers in the spring.
So I take it most people in Memphis with an older home DO NOT insulate the floors because of moisture and mold problems. I can see how that could be an issue. I know for a fact that I have moisture problems because my vapor barrier looks like a cheap plastic drop cloth you buy to cover furniture when painting. It's really thin. I plan to get under there this spring and put down a 6mil vapor barrier. (It's an adventure to get under a 50+ year old house to say the least!)
Chi....I don't understand what you mean when you say "button up your crawlspace but provide ventilation". Button up as in cover all the vents in the winter? Thanks!
When I say button it up, that is in conjunction with the proper ventilation I mentioned. In a perfect world, you can install temperature controlled vents to replace the standard contractor grade aluminum that they used 50 yrs ago, they make them in the same size. The benefit to you is that you never have to get under the house to remove/replace those homemade (impressive actually - props to the prior homeowner) "covers". In this area of the country, we have many days when the ambient temp is quite variable. You can seal it up in December and open it up in March, but really, what about those days when it is 35 degrees in the morning and 60 in the afternoon? The vents I refer to open and close between 43 (fully closed) and 48 degrees fully open).
I am not saying spend a ton of money to insulate from the outside, but if you have a cheap crawldoor and a drafty crawlspace with vents closed, you want to take care of that as you do not want pipes to freeze. You can buy a new crawlspace door if yours is a piece of plywood that doesn't fit properly, or you can have one built with TREATED wood (termites ;-))
INcidentally, if the plastic vapo barrier that you have is not degraded in any way, it is still effective. 6 mil is ideal, but plastic does not let moisture through. You want to make sure that you direct the release of moisture where you want it (where your best ventilation cross is). You only need 80-90% coverage.
pfunk, there are different thoughts on your type of solution. If you were in an area where serious ground water was escaping and could not be ventilated from your crawlspace, I may agree that a total solution that you mention may be your only answer. If you do, make sure that you have they leave a reveal of at least 3 inches from the top of the barrier to the bottom of the wood substructure. This allows a for proper termite inspection. Every house needs some moisture content, and they alll differ. I would only suggest that you study tis very closely as I have rarely encountered a house that "required" that type of solution. It also tends to be a bit pricey vs standard poly/vapo/vent moisture mitigation solution.