Soil cover VB under enclosed pier cabin

[skiwest]

Going to VB (6mil blck poly) under cabin before we get any farther than the griders.  Don't have soil by peirs now as after a couple of inches its sandy gravel.  So drainage is great but worried about damaging VB over time as want to use as storage.

Plan now is to dig hole with hoe to "mine " some sandy gravel and dump on area under cabin.  Rake out rocks so mostly sand for 1-2".  then put down some geotextile I have for road parking areas.  (now that I know the ground I probably didn't need it.)

Put poly on top of that.  then another layer of geotextile, then dump more sandy gravel again remove rocks ( most) 1-2" thick.

I do have a couple hundred sq ft of old carpet and was wondering if I could put that under poly also in high traffic area ( near door)?  Also have waste beadboard 1/4" that was thinking why not.

Any thoughts on plan.

[John Raabe]

With sandy soil you should be fine with 6 mil poly on the soil directly. The geotech fabric could be used on top or below as a protector but is unneeded otherwise since it appears drainage is good and silting is unlikely.

Mike Oehlear in the "$50 and up Underground House" book uses carpet directly on poly for many of the floors in his simpler houses. That should work just as well in your skirted crawlspace for protection of the plastic. It should provide you with dry storage.

[glenn kangiser]

We did a temporary Oehler earth carpet floor in one area.  Compacted with the plate compactor and water - let dry put the plastic then the carpet.  Works great.

Great on the low tech studies, John.  I'm proud of you.

[John Raabe]

I've learned right here on the forum at the knee of the master!

[glenn kangiser]

I guess it goes both ways.

[skiwest]

right now the top layer is kinda rocky so think need some sand to fill in between rocks.  I was thinking of geo just as protection not for its filtering ability.

Carpet on top.  have to think about that.  Ground dries supper fast in summer.  But in winter can end up in spring with 2-3 feet of wet snow on ground.  At that time everything is damp as water has no place to go.  Everything under cover rusts.  mildew is not a problem in summer but is in late winter/ spring.  Even with cover carpet on ground would become mildew factory.  MAybe if I could find some scrap astroturf stuff later that would work on to of the sand.

[glenn kangiser]

Maybe geo-tex fabric and sand to protect the plastic from rocks - then plastic - maybe double then indoor out door carpet - the water should stay under the plastic in the soil.

[JRR]

Hmmm,  how 'bouts a thick gravel layer for drainage ... then the geo cloth to prevent sand penetration ... then a layer of sand for a workable "bed" ... then pavers (Bricks, or flat stones, or concrete garden "stones", etc) just laid in for the high traffic/loading areas  ... "walkways" or islands.  

Gives you a surface that will take some abuse, but should never cause a lasting wetness problem.  Can easily be reworked later.

[skiwest]

Don't think I need more gravel as I've gone down 6 feet and there's lots of it.  

Do have slope from cabin outward , so drainage not issue.  Might scrap down area around for more latter.

Good idea on pavers.  Might just put down scrap OSB for now and see how that holds up over winter.   If doesn't hold up then just throw it on the spring fire.

my idea on the carpet was just to protect poly as won't be able to get all of the rocks out for gravel and the sand itself is pretty course.  Same with the geotextile.  Its more that I have extra and I have it than anything else. Also it should hold up pretty well.