What Is The R Value Of 6 Mil Plastic
By the time 1970 arrived uv inhibitors were added to give the plastic a longer life span.
What is the r value of 6 mil plastic. A perm rating of 1 0 for any material is defined as follows. In the 1960 s 6 mil polyethylene sheeting emerged on the scene for hoop house style greenhouses. 18 3 6 x 100 600 increase in r value. Typically a single layer of polyethylene film has an r value of approximately 0 85.
The following are some examples of material comparisons. 6 mil plastic is economical. 6 mil plastic poly sheeting. Make the most of the variety of uses of the husky 6 mil heavy duty clear plastic sheeting.
If you have pulled your sheet of plastic taut but with a layer of still air between the plastic and the window then you have replaced an air pane assembly with a total r value of about 1 2 with an air pane air plastic assembly with a slightly higher r value perhaps 1 9. It comes in a variety of thicknesses with 6 mil being very common. Therefore double pane is the better more efficient choice for a greenhouse glazed with glass. Now we can calculate the inverse to determine the true r value.
Typically a single layer of polyethylene film has an r value of approximately 0 85. A double poly cover consisting of two layers of poly has an approximate r value of 1 25. In my opinion increasing r value to reduce the rate of heat loss in a roof is entirely and only theoretical. A double poly cover consisting of two layers of poly has an approximate r value of 1 25.
My inspector just came back from a training session with the impression that michigan code requires a 6 mil plastic interior. Back then and even today its greatest asset is its price. I m about to start building a home in michigan s upper peninsula in zone 7. I planned for r 40 walls with cedar shingles over cedar breather over 15 felt over osb over 1 1 2 exterior polyiso board over 8 inch studs filled with blown in fiberglas and air sealed drywall.
This is a quick inexpensive fix but is it really inexpensive when you add in the labor cost to replace it more often than other options. When selecting a 6 mil greenhouse plastic you need to make sure it is not a product out of china. To convert this si unit to an imperial value we need to divide the si thermal conductivity by the conversion factor of 1 7307 when we do this we find that the imperial thermal conductivity is 46 1 7307 26 to 52 1 7307 30 btu hr ft f. If the effective r value of the original assembly was higher your.
However moving right along to viewpoint 2. This husky plastic sheeting is easy to trim to any size to accommodate your needs. Perm is a quantitative value that measures the relative ease with which moisture water vapor will pass through a material. 1 grain of water vapor will pass through 1 square foot of the material when the moisture vapor pressure difference between the colder side and the warmer side.
It has a 6 mil thickness and measures 10 x 25. It is made of eco friendly recycled plastic which makes it an environmentally friendly solution. Single paned glass has an r value of 95 compared with a double pane which is 2 0.