Crawl space air quality / Discussions

...crawl space that smells. it appears to be dry. and it smells musty. I have aapllied 20 mil poly on the dirt floor. And it still smells. I want to seal the odor. the walls are cynder block 3 feet high. Than dirt floor covered with 20 mil poly, Then floor joists above.  I was thinking about sealing the cinder block walls...

...crawlspace, but if you do, see here on how to insulate a crawlspace properly to avoid mold and heat loss. And no, we would not recommend creating negative pressure if you close it in. Make it as airtight and moisture-proofed as you can and manage any moisture there is with a dehumidifier. There is also the matter of bu...