Way to simulate a double-roof with convective air-gap system in HoneyBee

For passive cooling strategies, many times 2 materials are used for roof of houses- which have an open air gap - ie the air in the gap is free to escape to the atmosphere if it gets too hot, and is not permanently sandwiched in between.

This is different than the double glazed windows where air is trapped in between and behaves like a true material of thickness t.

Is there a way to model this situation in HoneyBee?
Representative image of this situation.
res

Hey @Nimish ,

If you’re confident that there will be good circulation beneath the two layers and the outer layer has relatively good thermal resistance, you could just model the outer-most layer as a shade material. Otherwise, you can model the cavity as its own Room with a high infiltration value to account for the air circulation.

Thanks Chris

All good suggestions - will work on it and update.

Hi @chris,
I’m in the same team as @Nimish. I have tried both ways of simulating the roof and compared it with a normal roof. I have observed that indeed the overall temperature falls as expected when I model the cavity in the roof as a room with a high infiltration rate. But I hardly see any change when I model the outermost layer as a shade.
I was expecting that shading would be able to reduce the overall temperature as well but the model results do not reflect that. Why is that? Is there anything I am doing wrong?
Attaching the file through the google drive link.
https://drive.google.com/drive/folders/1IX9mMVRzhDb0xsU2mSjEzkBejy8F3j7G?usp=sharing

Thank you.