Hi folks, I’m fairly new to Sketchup. I’ve got a model and a section plane cutting through it to give a perspective section view. I want it to show sunlight coming through real openings like windows but NOT through the ‘false opening’ that the section plane creates. Right now I have cut my building in half with the section plane and the half that’s ‘open to the elements’ for the purposes of the model wouldn’t actually be open in real life and so wouldn’t allow light in. Hopefully that makes sense. Is there a way to easily fix this? Thanks
Right click on Section > Create group from slice > Fill that group with a face > apply a material onto one face and set transparency to 0.
Ok that sounds doable, thank you! Not got time to try it straight away but will get there at some point and let you know if I have any issues. Appreciated 
Just got around to trying this. It’ll be too late for my deadline this week but be good to know for future reference. I couldn’t get it to work in my use case because I want to be able to see through the face that would need to be opaque as I’m viewing the room from the opposite side to your example. Is there a way to make this work? Eg. To hide the face that’s opaque but still make it cast shadows?
You can unhide the face, and paint the outside surface with a material that has a 100% transparent PNG image as a texture.
Using a renderer, V-Ray in this case, I created an object that covers the entire section, to which I applied an ‘Override’ material, and then I rendered
The shadows will be the same as when it is closed, but you will see it in section.
Really helpful thanks. I don’t use V-ray yet but will keep both suggestions in mind - thank you!