Usually it's paper side toward the insulated space, depending on your area, but for humid areas with A/C it may be, paper toward the heat, check with your local insulation supplier .

But often they are also a source for moisture, water accumulation, humidity and worst of all - mold.If the structure was built properly and is not old, basement is a great asset.

We use those with a humidity detector as most people turn it off after the shower & the steam just lingers.Check to make sure it vents outside & not into the attic as most do to expedite the job....mold is a nightmare.

I also make sure to plug it in and set the humidity level myself as the tenant will never do it.

It can alert me for high or low temps or humidity etc.The Encode allows me to add or delete codes as needed up to 30 at a time.

If the surface is wet or if humidity is high, polished tiles can definitely be slippery though.

Especially in the humid South. 

I'm in the south and daily temperatures are in the 80's so I'm slightly concerned about heat and humidity leading to mold or a foul smell.

We live in the south (New Orleans), so naturally life is incredibly humid.

The tiling in the bathroom alone is labor intensive and extensive because it needs to be prepped for a wet and humid location.