What does u number mean

[mike rexing]

Hi On manufactured homes They always give you a U rating instead of a R rating
for walls and flooring.Why is that and how do you know how good it is insulated.
Because I seen a 1978 Mobile home 14x66 have a higher U value then mine with 4in walls.and a Furnace that could heat at 70 degrees at 86 below and degrees at
36 below 97% of the time.My home is a 1990 6in walls 14x70 my furnace can only
70 degrees at -45 and 70 degrees at-10 97% of the time.What is this U value and why do they include the duct work also.I thank you for the answer for the last question and I know you will help me to understand this.Take care.

Don't Worry Be Happy!
Mike

[rmurray]

Definition is:

"A value that describes the ability of a material to conduct heat. The number of BTU that flow through one square foot of material in one hour. It is the reciprocal of the R-value (i.e. U-value = 1/R-value). The lower the number, the greater the heat transfer resistance (insulating) characteristics of the material. "


LOWER IS BETTER.

The calculation you see on the data plate includes the windows and ducts because they can be huge energy drains..The calculation also considers the tightness of the home if it is set up right.

There is far more to energy efficiency than R-value

If you bought he home new..you got a separate R-value certification..The temperature calculation is the manufacturers certification of performance of the furnace combined with the energy resistance of the home..If I remember right the manufacturer has to guarantee these certification...The temp is measured outside 5 ft above the ground in a shady area just as the "official" temperature is..

Inside it is measured 5 ft from the exterior wall and a certain number of feet from the cieling...Maybe one of our more savey posters will have a more exact explanation.

Sounds like you need to move South and only have to worry about the +100 degree days..

Smile..