Shop Moisture Barrier 6mil plastic [Stop Ground Moisture from getting to your shed]

[@jllaine]

Looks like that was much easier than crawling under to retrofit the other shed, well done!

[@sethcraftworkshop]

Yes way better to do this upfront!

[@davepelfrey3958]

I was thinking the same, until I saw the other was opened and it drains in that direction. But, good catch on that.

[@sethcraftworkshop]

Any water that does get on the plastic drains out quickly from the far end. This type water barrier is great for the area I live in.

[@BTReese]

I’m in the camp of this causing almost as many problems as it solves, also adding more work and expense which most people won’t like. My biggest concern is that one of the most integral parts of the build is still unprotected…the 4x4 foundation runners (4x6’s should be used on a building this size) if those are 6x6’s forgive me, I can’t tell in the video. Here in East Texas we have extremely wet winters and spring, followed by extremely hot and humid summers, and sometimes go two or three months without rain at all, during which times everything dries out, believe me. You don’t say where you are located other than it rains frequently. Location and typical weather are extremely important as to whether to do this or not. I always build as if it’s to last a lifetime, as most people should if they can afford it, but after my 60+ years I’ve learned that reality is that within 10-15 years I’ve moved on to something else. At this point, I’m only building for something that will last around 20 years and that’s good enough. That being said, a raised foundation on blocks with treated lumber alone will definitely last at least 20 years. If I put down plastic it will be under the blocks and everything. Rodents will chew through your plastic within weeks rendering it almost completely useless unfortunately. Plastic, then gravel, then blocks and treated lumber is the ‘lifetime’ method. You can be commended for a better than nothing method, but this really isn’t demonstrating a recommended way of doing this.

[@sethcraftworkshop]

I lived in NM for 7 years. HOT and very dry. One year we got 11" of rain. Here in NC we have gotten 11" in 1 week before. Recently I pulled some 4x4s out of the ground after 10 years. They looked new. These 4x4 skids on the shop should last 80 years easy. They are not getting exposed to rain or sun. The moisture in the ground here is incredible. Much better to have a layer of plastic down. You are right. It depends on the place you are building. Here its good to have a moisture barrier down.

[@michaelbradford4444]

Having 30 +yrs. framing experience I've seen and done most everything involved with building and the plastic cap nails are what we call button caps in SE Tx. and one of the many things we use them for is nailing down roofing paper. A lot of guys that do shingles full-time have their hammers magnetized and will place the button caps on the head of the hammer and drive em in !

[@sethcraftworkshop]

Thank you for watching. I just used the button caps for tyvek home wrap and for the roof underlayment. They are very handy. Magnetized hammers seems like a fun way to drive the nails. Also must take some sills!

[@algoodmonin2172]

Actually, this is the place where all the moisture will now collecting. No wind is here, and under temperature the plastic starts to make and collect a moisture. I would raise it up to couple blocks and leave it.

[@sethcraftworkshop]

So far no issues with moisture. Now if you peel back the plastic the ground is wet. On top of the plastic things are nice and dry. The 2' open gap at the end seems to let in plenty of wind to help with any moisture.

[@algoodmonin2172]

@@sethcraftworkshop I will build a shed the same size as you and your video is a great example for me. I'm thinking about insulation from below, but have not yet come to any decision. You've done a great job laying down the plastic, but if there's a small crack in it, nature will come in with a vengeance. Perhaps this is the best solution today. I just don’t understand why you didn’t tighten plastic but let it loose?

[@1Tibs1]

It’s similar to a crawl space, but the way he did it really makes sense as it slopes down if rain water and the ground water will also be kept away from the flooring of the shed/workshop.

[@rashellyohn5128]

I have been watching your vids on foundation because I will at least get the foundation done and then maybe hire help for the rest. You stated that you had mold issues and that you tacked plastic under the foundation and that helped. I have a old house that has many issues and I am afraid of mold only because the moister level is high. The windows are always running with condensation in the winter months. However, the crawl space will only allow me to get about 6" from one side. One end i can be on all fours, the other side I'm am doing an army craw of shorts. I'm thinking this would help but if I can't get to all of the underside of the foundation then it may not be worth it. It rains so much here in OR.

[@coodyl]

Coming along really well now👌🏻

[@sethcraftworkshop]

The next step is the frame build! That is where the fun begins.

[@alienpredator007]

Are you sure the mould isn't caused by rising damp through the footers? Building a shed at the moment and undecided between moisture barrrier on footers only/entire base.

[@gthree0239]

Obviously I’m too late for you to do but did you consider painting the bottom of the building with a moisture repelling coating? Instead of using the plastic?

[@sethcraftworkshop]

That could work. I went with the plastic because it is easy and cheap.

[@BrittCHelmsSr]

It seems like at @4:44 that it would have made more sense to just go over all of the timbers (like you're doing on the side closest to your existing building) rather than cutting the plastic at each of the support blocks that can then allow water to get into it. Just a thought....

[@sethcraftworkshop]

Ah. Yes that would work. As long as the ground is covered I think this is going to work well. Either direction that you go as long as it blocks the moisture from hitting the floor of the shop.

[@larrykent196]

Here I am wondering about the idea of the vapor barrier on a shed floor. I have read a bunch of comments from many others about this, and this video shows it done. Condensation could be the enemy here, those days when a few degrees matter and dew points meet then wet it all becomes, plastic sure holds water leaving only evaporation into steam its only escape and it will go right up into the timbers. Not so sure its a good idea. I am beginning to think the breathable landscaping cloth might be the best solution. A reduction solution may be the closest you can get. Anyone else have a comment, please do. Cheers!

[@sethcraftworkshop]

I have three buildings on my property and each have vapor barriers like this. My first shed did not have a vapor barrier.And I had a serious mold issue. I climbed under the building and placed a barrier and no longer have that issue. If I lift up the plastic, there's obvious water drops coming down.However no moisture seems to be up against the building.

[@larrykent196]

@@sethcraftworkshop I took your advise and put a vapor barrier down over my block then the frame went on. Thanks for the tip. Cheers!