Yesterday, temps were ~ -10F.
> We put a temp sensor (used plastercine), on the
> center of a 40"x 40" window and recorded +60, with
> the indoor temp being +65.
> Next we placed the sensor on the wall beside the
> window (same height) and got +63.
>
> The wall, from in to out, has 1/8" paneling, 3.5" fiber
> glass, 1/2" plywood, 1.5" sm styrofoam, covered with
> vinyl siding. Could we calculate the R-value from that,
> and then calculate an R-value for the themal window?
>
> We flattened the plastercine against the wall with
> the sensor in it, it's fairly accurate (better than =A0+/-1 F)
> and left it until it setted, so the measurements are
> fairly scientific.
> Ken
Get one of the IR thermometers that do spot readings. Point and read. They're cheap enough and will give you a surface reading, not an air temp reading. An air temp reading will most likely be misleading, and not be suitable for calculating values.
R