Crawl Space Problem #5 - Soil Gas Ventilation | Which System is Best

[@jeffbrown8408]

very helpful thanks so 3😅

[@CrawlSpaceNinja]

Glad I could help. Thank you so much for watching.

[@IWestexI]

My home has recently had a pungent musty smell (no ferrets 😅) and i opened the crawl space door and was hit in the face with that same powerful stench 10x and it was mold. Hopefully you guys can help us in Raeford NC. Thanks for the great videos!

[@CrawlSpaceNinja]

Yikes! We here at the DIY Store can help too! - [e-mail]

[@sjpropertyservicesllc9096]

Thank you for sharing! An informative series of videos.

[@CrawlSpaceNinja]

Thank you so much for watching.

[@kylekelley213]

Love the content, loved the series. Radon should be below 4.0 pci/Li in a real estate transaction. It is achievable and should be under 2.5 pci/L per EPA.

[@CrawlSpaceNinja]

Thank you and thanks for sharing.

[@abrunson]

QUESTION: If someone is doing a DIY encapsulation (removing insulation, remove old plastic, add foundation insulation, add new plastic (10 mil) on ground and up wall/pillars, closing foundation vents, adding 1 foundation vent, adding dehumidifier --- what order is best assuming this may take a few months. Home is in middle GA - approx. 2000sf crawlspace.

[@CrawlSpaceNinja]

Dehumidifier, seal vents, install ventilation fan are great phase 1 steps. Then remove insulation, mold, then insulate, remove old plastic, install new plastic. Hope that helps.

[@abrunson]

@@CrawlSpaceNinja - That gives me a plan... and I'm glad b/c I was gravitating toward insulation removal ahead of Dehumidifier, seal vents, install ventilation fan. The only issue that you can't solve is that my crawlspace is only about 18" - 24" - and less where where are house jacks/beams ... but that is what it is. Thanks again. Love the channel.

[@cjhnsn20]

For a small 11’x12’ ft encapsulated crawlspace (132 sq ft), is having a ventilation fan in such close proximity to a dehumidifer going to cause any condensation issues?

[@CrawlSpaceNinja]

Great question, it probably won't cause condensation issues but it could be blowing some of your dry air out which is not very efficient. In that case, you could consider a low volume radon fan under the vapor barrier. Hope that helps, thanks for watching.

[@angkeats3685]

Love your videos. Any recommendations for a cold climate winter -18 if I encapsulate my crawl space and use foam board for the walls, is that a good idea? Dehumidifier as well

[@CrawlSpaceNinja]

Yes, absolutely

[@JW77]

Your videos helped me A LOT! I've been trying to figure out what's the right way to convert my crawlspace from vented to unvented and the information out there is really confusing. Thank you for sharing your knowledge. In the drawing at 14:30, the supply air for the exhaust fan seems to come through the air leaks from living space. I just air-sealed the top and bottom plate of all my walls with orange Great-Stuff. Does this mean I should cut some of them open?

[@CrawlSpaceNinja]

Great question and thank you so much for sharing how our information has been able to help you. No you should not need to remove any spray foam because the soil gases and sill plate should provide make up air. But if you find that is not the case (hold hand over fan output) then you could do a small amount of foam removal but I really doubt that would be needed. Hope that helps.

[@timothyraytaylorjr1224]

Ac flooded crawl space now my whole crawl is fudged up ! Sub floor and joist need replacing now . Should I encapsulate. First then fix sub floor or sub floor joist and then encapsulate ? Any help would be appreciated sir thanks

[@CrawlSpaceNinja]

I would get the wood dry and replace any wood that needs replacing before putting your new plastic down, you can leave your old plastic in place to help dry with the dehumidifier. Hope that helps and sorry to hear this happened yo you.

[@Crypto-Cod]

Some of my neighbours Have installed. A Positive input vent in the attic which has a filter. IT trickles air in via a ceiling vent, which suppose to give a slight positive pressure.Aim to reduce condensation. On widows. They say they have great results. However they haven't addressed there crawl space. Great video. Thanks Dave. U.k

[@CrawlSpaceNinja]

Thank you for watching and sharing your comments.

[@AmericanPatriots87]

Hey Michael, thanks for all of your informative videos. They really help. With that said, I'm currently in the process of having my crawlspace priced out and one of the companies wants to fully encapsulate my crawl space but said that the fan you are recommending is unnecessary and that if I don't put in a sump pump with drainage matting that my crawl space will start to smell like cat pee or ammonia. I thought that was from people using the wrong vapor barrier to encapsulate? They claim they want to put a dehumidifer with air purifier to manage the air in my crawl space. While I see that controlling mold or other forms of contaminates, I don't see how that could control soil gasses.

[@CrawlSpaceNinja]

Thank you so much for watching. Dehumidifiers are designed to control moisture. Not soil guesses. The reason for the fan is to move soil gasses out of the crawl space. A sump pump with drain mat is usually not the cause of the cat pee odor. Cat urine odors usually come from debris left behind under plastic and vapor barriers that separate and trap moisture over time because there are 2 pieces glued together in my experience. Hope that helps.

[@RJMillaway]

Help me make sure I’m doing everything right. Your channel has been very helpful. I diy encapsulated my crawl space. Did great job eliminating moisture with Santa Fe dehumidifier. I somehow missed in my first initial research that I needed to pull air out for gases however so for year had no vent fan blowing air out until I reviewed your videos and saw that you mentioned that was necessary. We only had a couple small 1-2 inch vents that I closed off before encapsulating. So my solution to install a vent fan was to integrate it in my crawl space door. It has worked good for last few months since then but was under checking on it and have found that half of my crawl space feels humid now. I have a 1500 sq ft crawl space with a block wall don’t the middle with opening dividing in half. The main half has the door with air vent out, dehumidifier as close to the opening that I could get (the dehumidifier wouldn’t fit above or below main drain line that runs across) with the dry air blowing toward opening. That main half seems to be and feel perfect but that’s second half now feels humid since adding air vent. Where do I go from here? 😅

[@CrawlSpaceNinja]

If the fan is too close to dehumidifier it could be pulling dry air out before it can get to other part of crawl space. If dehumidifier is located on door side, I'd put fan on other side of wall so dry air can be move toward that area. Also small amount of cfm, not sure what you are running but 110cfm or less is good. Hope that helps. Thanks for watching.

[@RJMillaway]

@@CrawlSpaceNinja Thanks for the reply! Its isn't terrible close its close to the opening to other half of crawl space a little more then half the length of house away. But it does blow the dry air towards the fan. I looked it up it says 240 cfm so should I not have that on high then? And for fan on otherside should I have it blowing air into that second space that is humid through opening or out of the opening towards the dehumidifier? I have thought of getting another dehumidifier on the otherside but dont think it would fit above or below the main drain pipe that runs accross the whole thing before opening. Sorry so complicated just trying to figure out what to do to fix.

[@TagiukGold]

This is so insightful. And slightly inciteful😂

[@CrawlSpaceNinja]

Lol. Thank you