How to define reflectance of near infrared of solar radiation

Hi.I'm natchan.

Im investigating reflected light of sun from glazing of buildings with

Radiance materials can be set reflectance of each RGB.

Then, can I define reflectance of near infrared(NIR, unvisible light) of
solar radiation?

Is the NIR reflectance equal to RGB reflectance?

I apologize for my poor English.

Thank you.