In general, crawl walls should not be covered with a vapor barrier, as per Building Science Corp., but instead, insulated and air-sealed.

If there is a vapor barrier under the concrete flooring, there's no need for a vapour barrier. But if there's not, I would still be inclined to leave it as is. Otherwise, water vapour moving upward into the crawl may be trapped and become water feeding mould growth.

Keep in mind that crawls in the Pacific Northwest are best treated differently.

I’m in Canada - Alberta, with cold winters and very warm summers( this year at least!)

The building inspector suggested fixing the vapor barrier which was ripped. He said we are getting the ”stack effect”

There seems to be a little mould on the walls of the concrete part of the crawlspace. There is no vents or anything in the concrete part. Im going to check the humidity and put a dehumidifier down there this weekend.

Thanks for the help I will look more into the vapour Barrier

My AC company referred me to an exterminator who encapsulates/seals crawl spaces and installs dehumidifiers. Totally different climate, but if I were you, I would call around to foundation, hvac and exterminator companies in your area, and get someone reputable to come out and do an assessment on your space. Or at least look at their local websites to see if they have information on the best crawl space solutions for your area.

I am getting ready to install floor tile and the health of the subfloor above the crawl space is a big deal for me.

I think the company used a special type of vapor barrier (8 mils) and a special type of dehumidifier. They drained it to the outside and gave me a remote meter. (We don’t have freezing weather here.)

Even in summer, Big Sky Country hits no more than 45% rh. Still, pretty much the same solution as in the humid US southeast where crawls seem to be a big thing. You just need more insulation on the walls.