Help!How to calculate heat load with resistivity values?

[jbomba]

Hi there i am currently doing an assignment, im trying to work out the heat load of the structure of my cold room. I have been given the following data to work with.

* The room is 15m x 10m x 5m
*The walls & ceiling are 150mm thick & are typical rollbound construction, 150mm polystyrene sandwhiched between 1mm sheet steel
*The floor is 200 mm thick , again of rollbound construction, it is standing on a 200mm concrete slab, the concrete slab is standing on the ground
*The ambient temp surrounding the room is 25 degrees celcius, The RH is 60 %

R1, Thermal resistance ,air film on outside of walls & ceiling is 0.03 W/m2/K

R2, Thermal resistance ,air film on inside of walls & ceiling is 0.12W/m2/K

R3, Thermal resistance, sheet steel 0.021W/m thick/m2/K

R4, Thermal resistance , polystyrene 28.9 W/m thick /m2/K

R5, Thermal resistance, concrete 1.07 W/m thick/m2/K

Now how would i go about working out the gain using a resistivity formula , i seem to recall it was similar to working out the resistance of an electrical circut in paralell.

Is this the formula here? resistivetey/m thick/m2/K with K being the out side ambient? then once all the equations have been solved i go R1+R2+R3+R4+r5=??

Thanks in advance if anyone can help me