Do it in where you think the moisture is coming from where the mold is worst.

Stuff can get in there, like moisture, and who knows what will grow. 

If your studs are contracting and expanding, you have a moisture issue and insulation problem.

Termites feed on wood, and they usually get into the buildings with areas excessive moisture (leaks, frame in contact with soil, etc).

@Sriram Kumar Bikkina My guess is that your friend may be trying to bring awareness to the fact that crawlspaces can typically create alot of problems particularly moisture intrusion, dampness, mold, etc. and can lead to moisture damage to framing components.

I’ve also had issues regarding aluminum wiring, electric panel not being up to code, rotted wood from a ton of moisture, and foundation issues.

The building inspection uncovered that the new house foundation is just sitting on top of the old one without any stabilizing measures.The crawlspace was largely inaccessible to the inspectors, but what they saw was mold/moisture issues.

The moisture from the carpet cleaning gets under the carpet tack strips along the edge of the room - where the baseboards are - and the moisture could lead to the mold becoming established there.

In all of our properties, when mold appeared it was because the tenant had not called us about a water leak, or created too much moisture and didn't use the ventilation fans as they should have, or did not use the heating system properly, or kept an unclean home. 

Watch out for moisture as well as having them heat and cooled.