I want to insulate my floor in my house if i do so do i put up a plastic sheeting after i put in the insulate?

The plastic sheeting serves as a vapor barrier, and is needed only if your house is in a region where outside temperatures drop below freezing. The principle is that air inside of the house has moisture--from your breathing, from cooking, from the bathroom, and from your humidifier. Without the vapor barrier, the moisture will get into your insulation, which has a temperature gradient with the inside surface at room temperature and the outside surface below freezing. At some point within the insulation the moisture will freeze and ice will accumulate. This not only reduces the effectiveness of the insulation, but makes for a large problem in the spring when the ice melts.





You can see that the vapor barrier should be against the inside wall, so that moisture can't get in the insulation. If you insulate your floor, the vapor barrier must go up. That is why it is best to use faced insulation, with the face up. Don't use plastic sheeting in conjunction with faced insulation, as moisture can get trapped between the two.I want to insulate my floor in my house if i do so do i put up a plastic sheeting after i put in the insulate?
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I want to insulate my floor in my house if i do so do i put up a plastic sheeting after i put in the insulate?
The plastic sheeting is a moisture block.Put it up/down first. The your insulation.
If you are insulating over a basement you do not need or want a vapor barrier.


If you are insulating ove a dirt floor then the vapor barrier would face the unfinished part of the crawl space.
no no no no no
If you are insulating a ground level or below grade floor you need to build a frame from 2x2 strips and then fill in the spaces with styrofoam about 2 inces thick then lay wooden sheeting over the strips then nail the sheets to the 2x2 strips (which are anchored to the floor using tapcon anchors). No plastic is needed.
peeps are right about the insulation that has vapor barrier already on it.. barrier goes towards the room.. you do not use plastic if it already has the paper face on it.. double barrier is a nono. as the other said if its a crawl space put plastic down on the dirt/gravel
Yes The vapor bearier faces outside away from any subtstrates or wood.It keeps moisture from getting the insulation wet and helps stop rotting should the insulation get wet. I would use a heavy mil thickness on your plastic. I have done this projest, Not fun, but well worth it. Also there are wire hangers you can use to hold op the insulation, speeds up the process. Good Luck!
First use the plastic sheet..next put the isolation on TOP of the sheet.





Make sure the plastic sheet is large enough so the ends can be folded up by about 1 foot.
Not necessary.
I hope you mean under neath the floor. If you have a basement you need no plastic. If it is a crawl space you can put the plastic on top of the dirt
Check the specifications on the insulation you intend to use. Some already have a moisture bearer. You should be able to get advice from you local insulation supplier.
BEFORE you do the floor, is there plenty of insulation above your ceiling? I think there is where the payback for your effort and cost will be faster. Insulation above keeps winter heating in and in summer keeps summer heat out. Insulating a floor -- IMHO -- is much less important. I wouldn't even consider it unless there is an open crawl space under the floor and winter temps frequently stayed below freezing. (What region of the world is the house?)
vapor barriers go closest to the living spaces. just buy faced insulation and put the faced side up. if you have a dirt floor crawlspace or basement put the plastic on the floor, not the ceiling. home improvement stores have booklets in the insulation aisle on how to do it. good luck.