Why the color of this armchair is gray in my Renders

The material parameters are blank and no appearance assigned to the model, you could try add material to the model appearance and it should show different colour when rendering. Thanks for letting us know the issue and we will pass it to the manufacturer.

Revit 2015

Fire stop, I'd check the render settings ;)

I think for this BIM model you need to assign your own materials/textures to it

yeah got it , thx a lo t.

What software do you use?