Slight variance in floor (normal mapping?) What I am trying to achieve is


Semi-gloss floor (light grey E7E7E7)
Slight bumps and nicks in the floor (normal map?)


I've taken my floor plane and applied a normal map as seen here (LINK) but now I am trying to figure out...


How do I keep my Glossy BSFD shader of a light grey with roughness of 0.65 AND have the normal map laid out on top of that? When I appoint the normal map to a diffuse and the floor colour to glossy and mix them both, then I end up with a colour different than the floor should be (lighter)
How do I ensure the normal map disrupts the reflection of the Glossy BSFD?
How do I change the intensity of the normal map?


What I'm trying to do here is have a clean semi-gloss floor, but with slight varience
There are several things you could do, one way would be to put the Normal value into the Glossy BSDF shader as well as the diffuse:





However I would recommend using the Material Output node's Displacement input. I find that it works very well though in many instances, your type of scene especially.



Here is an example of what it does:



You can do this with any texture, from noise to musgrave to image to normal, they all work using this method. Now of course, the mesh profile will not change like with a real displacement modifier, but in your case, this doesn't matter, as you only want it to look like the bumps are there, and unless you put the camera right down next to the boards looking towards the horizon, you will never notice the difference, Much faster too.



You can also change the strength by using a Math node set to multiply:



You can find this node under Add > Converter > Math.

You can now change the height of the bumps by changing the lower Value up or down.



You can also use negative values to invert the bumps as well.



In your specific instance, you need to set up your nodes like this:



Then you might want to re-make your floor mesh, as currently it is made from many N-Gons. Anyways, be sure to change the Mix shader value, it is set so only the glossy will show (1.0 glossy shader)