New Build CrawlSpace does anyone have experience

[HBxNLmaster]

Well after a lot of thinking and pondering i have decided to use my crawl space, here is what i am thinking, right now it is 3.5 feet tall so i thinking that if i dig down another 3.5 feet it would give me around 6.5 foot of clearance after the floor goes in. i am tall and wanted to be able to stand in room. after digging down i am going to line the whole with 2 layers of pond liner like you use for a coi pond. on top of this i am going to put stepping stones i was thinking 3 per row and then put a 4x4 treated board on top of this. i was going to do 3 rows of this and then put plywood on top of it. over all the floor will be 6x8.

So is all i have really come up with after this there is a few diff options and was hoping that some people with experience would help me out. the easiest way i can think of would be just to buy the xxl ten from htg supply and set this on top of the floor, but not sure if they are strong enough to keep out the humdity or mice or spiders or anything else that is in a crawlspace. The other options are to frame up walls with 2x4s and use osb or use 1x2s to frame up with and that blue insulation boards that are silver on one side and blue on the other it comes in various sizes but i would use atleast 1/2 inch but prob 3/4 inch. the latter would be easier and prob will be the way i go if i dont get the tent.

anways let me know what you guys would do if u were doing it i have 2 digital 1k lights and a 6 inch fan with a can filter i also have hydrofarm light mover. I am gonna stick with DWC set up for now. oh and the intake air is going to be coming from my bedroom which i keep at 65 degrees all year around with a window ac if needed. i guess i will use like three 6 inch peices of pipe as intake will this be enough?

anways has anyone grown in a crawl space is there any unforseen problems i am not thinking about?

i am open to any suggestions as it will be about two weeks before construction starts becasue right now i am putting up a new cover for the crawlspace so that it doesnt have to be replaced after the room is in place.

 

[humble1]

#1 drainage.
depending on how your house is situated, two layers of pondliner won't mean diddly if they only go 12" up off the new ground level you're planning to dig. every house and every situation is different, but most of the time the water will find a way in. you could try to set up a sump pump and basin in there to evacuate the water. Do you know how moist it gets in there through out the year? I ask because it will be significantly more moist another three feet down. Also, have fun with the digging. I'd hire a crew of day laborers.
#2 mold.
It's always gonna be an issue unless you live in a very dry, arid environment. If so you may be able to totally disregard my concerns above, but if not you're gonna learn how to fight mold. It'll probably be easier to manage in a tent, so I would go that route and just set mouse/rat traps for any vermin concerns.
Good luck!

 

[HBxNLmaster]

the digging i can handle it was the water issues that was worrying me too, i too was thinking that the sump pump might be needed but was hoping that the pondliner would help me not need this i was thinking that if i framed up the walls i could run the pond liner right up the walls atleast 2 foot above the surrounding dirt


also i do have access to a small dehumidfier but i was thinking that if the room is sealed and the air that im using in the room is coming from inside my house the humidity shouldnt be too much of a problem

 

[HBxNLmaster]

so i decided better safe than sorry about the sump pump i found one with a basin for like 180 bucks so i figure better to be safe than flooded lol. i dont think i will need it but id hate to be wrong.

but come on guys please give me suggestions on what to do i am not sure but i am leaning towards framing the walls up with 1x2s as i have some carpentry experience and then using the insulation i talked about earlier. i will run the pond liner up around the walls about 4 ft so its above the surrounding ground and then also using black poly around the outside taped to the pond liner and all the way up to the ceiling which is my bedroom floor. the door will be a trap door from my bedroom. the ceiling will be covered in reflectivex as well as the top half of the walls and if i have the money the bottom half to but might have to wait til after the first run for that. the reason im going to frame it up instead of use the tent is so i can make sure with the poly and the pond liner that i have an air tight box so no critters or unwanted strange under the house air will get in the intakes will all be right into my bedroom and the exhaust will run 24/7 and in the winter will be pumped into the house for extra heat.

so what do you guys think ? i have it all worked out in my head a smoke session earlier helpd clear the head also i was thinking that if i had to i could even run a window ac under there during the summer i dont think i will have to as my lights are air cooled but if i had to i think it would work.

one more question would you guys put the pump sump on top of the pond liner or under neath of it ?

 

[Dr. Buddington]

Usually if you have 3.5 feet of crawl space you will have maybe 5 feet of foundation wall, so chances are your room floor will be below the footing, which will definitely draw water in. You don't have to have high water table to get flooded, all it takes is rain. Is your crawlspace filled with gravel? Either way it will be a LOT of manual work man.
As for your sump, I would suggest that you spend a bit extra money and dig a bit more; for the sump to work for you it has to be in the lowest drainage point. You should dig a trench around the perimeter of your room, about 1.5-2 feet deep and install weeping tile (corrugated 4 inch flexible plastic pipe with holes) connected to your sump barrel. Then you just need to go with a level and ensure that all the weeping tile flows towards the sump from the highpoint located diagonally from it. Fill the trench with small rock/gravel any aggregate that doesn't have fine particles but is small enough to drain water well and viola! your room is virtually flood proof (granted that you plug your sump in and put a line leading to the drain for it). Just look up "installing weeping tile" on any search engine
Throw a pond liner and you'll be set. I don't know how cold it gets where you are but in winter that ground will be cold, if I were you, I'd put down some 3/4 inch plywood on the pond liner or put 2x4s under the plywood and screw together for an "insulated" floor. Hope this helps you man.

 

[HBxNLmaster]

thanks Doc i will look up these weeping tiles i hope they arent that costly, and yeah i was gonna dig the basin down below the 3 foot hole so as long as it is in the lowest part of the floor i think i should be ok, as far as the insulation goes i had not thought about that but i do have some extra of that pink insulation so i think i can just put it between the 4x4s i was gonna use to put the plywood on and i think this will be ok not sure tho but thanks for the input

yeah i know that it is alot of digging but i used to do construction and have spent many of days digging holes i am sure that this is manageable for me and i have a two or three month window to get it done as i am gonna do one run in the house but i eventually want it to be completely stealth if for nothing else peace of mind.

EDIT: I looked up this weeping tile which is a confusing name lol i have actually installed this stuff before i just didnt know it was called weeping tile i can and will install this weeping tile and think maybe i should just dig my hole a half a foot or so wider than i was thinking and make a trench all the way around my floor and put the weeping tile in it and then put the sump pump in the corner of the trench do you think this sounds right DOC? thanks for the help i can see why not very many people do this but for me its just for peace of mind and i think i might even wait to grow until i get this finished just so i dont compromise my living situation, i live here by myslef but my parent own the property and even tho they havent been in my house since i moved in id hate to get that call one day when im gone and they walked in a see my grow going. atleast they wouldnt call the the cops but they would prob kick me out and i run a small dog breeding operation and have no place to take the dogs if i get kicked out

 

[Beanfish]

You're more ambitious than I. Bunker digging and all. Lol.

Any idea how high the water table is? I'd have a sump pump and crock in there no matter what. Depending on where you live, you may have a tough time keeping the temps up in the winter without a heater, especially with lights out. I have to run a small heater during lights out in a heated basement in the coldest of winter months.

I'd go for a big tent. Easy (and fast) to set up/tear down. If you do run into problems, you can pull it out in a hurry and set it up elsewhere. If you hard frame and seal a small room and the thing floods or you run into mold issues, you'll have to rip it all out.

Just my 2 cents.

 

[HBxNLmaster]

yeah i do see where the tent would be easier but im just thinking that they dont make tents big enough to come through the top and stand in with 2k i really need about a 6x8 space taht gives me 4x8 for growing space and 2x8 for walking space. but i do see what you mean about it being easier to tear down and what not its something to think about while i work on the hole and the floor after i get that part down i think things will go alot smoother, thanks aloty for the reply tho as sometimes i think i am just talking to myself on here....lol. as far the heater goes yeah i plan on putting a heater in for the lights off time another reason i wanna have the 2 foot of extra space. as far as the problems go before i would lose a crop i would move them into my spare bedroom which i am thinking of running a crop in in the mean time. like i said they havent been here since i moved in but it would just be peace of mind to have it hidden this well.

thanks for the replys guys keep them coming im sure all you guys can burn one for me and come up with good ideas

i really need some genetics and i flat broke right now after buying the new under pinning. anyone have any gift seeds lol i know i cant get that lucky but i would return the favor later.
i love good indicas i might just make a small order from the botique and pick up a few nirvana strains and ideas on which ones.

 

[Bill Sussman]

Hey HB,
I currently grow in a crawl space underneath my house. At the time It was and still my only option as I live in a small house. I too was feeling strong and industrious and thought i could dig out 2+ feet of soil out of a 10x10 area. I FAILED MISERABLY. I tried digging it out in the summer time when the clay was nearly rock hard and stopped at about 8 inches. I'm glad I did too, now that it is the spring thaw I am having severe moisture issues with the clay, even with the poly over it. I'm also now noticing PM devolping down there now that it is moist.

Cons to dirt crawlspace growing-
Height
Possible moisture and mold issues during wet months
back pain
not so stealth an easy to break down in a plumbing or furnace emergency
possible bugs


Pros
Fairly good temps year round
out of the way/ discreet


I'd say if the crawl space is the only place to grow then modify your grow style for your new height limits. Something like a scrog with a 1000 or 2 six hundreds on a mover would work out pretty nice down there.

 

[inphu510n]

Man what an undertaking. Props for having the chutzpah to try to pull this off. It's a totally fun idea for a stealth grow. Going to be a pain to start the work but once you get down to your working depth you'll just be cutting straight ahead/side to side.

I just did a cursory check for tents and found this one at HTG which seems like it would suit your needs (unless I've missed something).
As others have noted, only thing I'd be really concerned about is rain and general moisture levels. The only way to tackle the latter is a sealed and controlled environment. Rain... well you've got that part figured with the weeping tile business.

GL!

 

[monkeysee]

Man what an undertaking. Props for having the chutzpah to try to pull this off.

Exactly what I was thinking.

Seems like a lot of work. I assume you own the house. Ever consider a shed or something in the back yard?

 

[Dr. Buddington]

Hey HBxNL, your plan for weeping tile sounds solid. I thought it was even more of a space that you were working on, because you also gotta think about carrying out all that dirt out of your place. If you are digging down only 32sqf down 3 feet that will give you 96 cubic feet of clay to dispose, and thats a bit suspicious IMO, coming from a house that is. Either way, you will need some gloves and a lot of motivation. Remember to take it easy, digging in 3.5 feet of crawl space is not going to be much fun, and its a lot easier do damage your body when you are bent in a few spots and working, unless you are some kind of a bodybuilding midget, that would be pretty cool. If you have any questions, just ask man.

 

[Che]

Digging a giant hole under my house vs renting another place to grow at.. I'd have to choose renting another place! Man you've got your work cut out for you, good luck!

 

[HBxNLmaster]

lol man the replies took off thanks for all the replies. as for the body building midget no but yeah it would kill my back but what i have planned is remove the peice of plywood right over where i am digging and the put it back when i am done, thanks for the reply Bill nice to know someone else is doing the same thing, i think the Doc figured out how to take care of the moisture problems for me and it might help you too. as far the moving all the dirt out i plan on just moving it to a different spot in the the crawl space as the space is huge and ill just put it in bucket and take it down to the other end, i in no way plan on doing this in a few days i will give myself atleast two weeks just for the digging part i wont get into any hurry cause i want this to be as nice as possible. I am planning on doing this all right so i can use it for some time. I have decided that with all the interest in this that when i get started i will post pics of the progress so that other will be able to follow along and it might be helpful to someone who is in the same situation. i will be posting from a diff name for anonimity purposes but you guys will know its me when you see someone doing this. Che as far as renting the house that might be an option if i was a cash cropper but these buds are for me as i have decided most will be seeded because i love breeding new seeds and varieties. I dont plan on selling these buds i will gift some of them to a few sick people i know but that is it. I also plan on donating some of my seeds to the boutique for fund-raising purposes. I am just notw getting started putting up new sides around the crawl space i hope to be finished by this time next week so i can start the dig which like i said will prob take me atleast 2 weeks maybe even a month but i am going to get it done i have a mattock a shovel and the big bar you use to help dig so i have all the tools i need even if run into a rock or two. I wish i knew a body building midget to help me but i don't if any of you do refer him my way..lol

yeah i know this is alot of work for some and prob too much for others but i am determined to do this and it will get done because its been to long with my equipment setting idle, i have two brand new digi ballasts that have never been used i used to have the growbright brand magnetic ballast but gave up on them and lent them to a friend because i had nothign but trouble from these, they would work great for a grow but then usually by the second one they would mess up the store i got them from HTG would always replace them at no cost but they are atleast 2 hours away so i gave up on them and upgraded to the digi's i hope they work better they are Digital Greenhouse brand has anyone used these are they good quality, when i get some money i will pick up an additiontal just incase i have problems with one i wont be without light.

as far as renting a house just for growing that is for cash croppers or rich people i dont by any means have the funds or interest in this, around here it would be kinda suspicous to rent a house and not live in it, its a small town and the judges around here are not so friendly besides like i said i used to grow for money but now its all for me as I need the medicine and want to be able to keep it all.


and yeah i guess you could say i own the house i mean my parents do but they plan on giving it to me some day, and as far as the furnace or plumbing being a problem i dont see that being an issue because if something breaks i usually fix it and my furnace is not located down there its upstairs and i can doing any plumbing issues that may arrive as i worked in a carpentry job for a couple of years it was a shitty job but atleast i learned how to do things like this on my own and i was thinking that it would actually be a plus cause i can easily tap into the water line and run a spigot into the room so i dont have to carry water down there.

 

[PharmaCan]

Might I suggest that you go outside your house to a location as close as you can get to where you want to dig under the house and then dig a test hole as deep as you want to excavate. This will not only tell you what kind of dirt you are getting into, but you can watch the hole for a day or two and see if it fills with water. If you're down into the water table at the depth you want to go, it's probably time to consider plan B. I once owned a back hoe and I helped build a few underground rooms. There's certain soil that you simply aren't going to dig through by hand, period. Hopefully that's not the case on your property, but it's a whole lot easier to dig a hole outside to find out.

For seasonal water, a curtain drain around the perimeter of your house will mitigate a lot of that worry. For that matter, you could dig the curtain drain just a tad deeper than your grow hole and that'd keep everything inside the drain (i.e. the ground under the house) dry as a bone. Depending on the slope of your lot, you might have to put a sump on the curtain drain, but it would be outside, as would the drain itself, and digging outside is a whole lot easier than digging under the house. If you live in an area where wetness is a problem, no one is going to even wonder why you are putting a curtain drain around your house. If anyone does question it, just smile and say "Too much mold..."

Once you have a dry hole under your house, you need to start with the floor. Remember that any cave-like space you provide is going to be a home for vermin and spiders. With this in mind, I'd dig a 4"x6" trench with the outside perimeter of the trench exactly the same perimeter as your proposed building. Set 6"x8" concrete block in the trench, backfill and level as needed. Dome the dirt inside the blocks a little, just as a drainage safeguard. Fill the blocks and the area inside the blocks with crushed rock, cue sand for the last couple of inches, install a visquin vapor barriar, 5/8" OSB board, cedar (not treated) 2x4's for floor joists then the appropriate plywood for a floor.

Frame up from the floor using 2"x2"s and standard framing techniques. Run 2x2 ceiling joists and support as needed with metal straps (you could even use plumber's tape) to carry weight. Insulate the walls and ceiling then drywall them. Wrap the outside with heavy, black visquin. If you use bats, or even just small pieces of bats with nails instead of staples, your visquin will last a lot longer. When you're done, you have a primo room inside. It'll be more work than what your are proposing, but the cost isn't going to be significantly more. Even the exterior curtain drain is cheap if you do the digging yourself.

If you use cedar in your construction and also put cedar chips around the outside of your underground bldg, it'll discourage insect activity.

That's my $.02. Good luck with your project!

PC

 

[Kalicokitty]

DO IT!
I love stealth grows in spots where people said it would be a huge PITA to build.
I like what Doc buds saying about how to handle the water/mouisture.

Frame out the room I'd say, put the time in and make it sweet!

Take pics too, lots of them, I love watching builds like this.

 

[humble1]

You better prime the shit outta that drywall with a couple coats of KILZ on both sides and maybe a separate vapor barrier, too. and invest in a sulfur burner; you're gonna need it.

 

[HBxNLmaster]

thanks pharmacan i already have a curtain drain be hind my house that takes the run off water from behind around and on down the hill, so that i have covered i guess that is lucky huh im sure its not as deep as the hole but its pretty deep as my grandpa did it and he over did everything, as far as the diggin goes the dirt around here is not at all bad to dig in i have lived here my whole life and dug many of holes around the property. the ground is not that hard. as far as digging under the house its not going to be as hard as you guys are all thinking because i am going to remove the floor in the house where i am digging and replace it after i get done. i am still going use the weeping tiles and sump pump under the room or actually in a trench just outside the room and i think this should take care of any water problems i will post a diagram in a little bit to show you guys what i am thinking of i like the idea of the cedar tho and will be using the chips like you suggested i dont know if i will use cedar 4x4s i would if i were buying new ones but i already have treated 4x4s and will use the ones i already have to save money unless you see this being a big problem, i dont like the idea of drywall though as i have seen what it does when you get water on it and dont wanna have to worry about it molding from water on it i think i will instead use the 3/4 inch insulation boards with the silver on one side and put the silver facing in and then cover this with reflectivex (insulation basically a bubble rap with metal on both) i am going to use your idea of putting black visquin on the outside of the room tho


thanks calicokitty i need all the good vibes i can get i know it will be a pita but i am gonna get it done i will be posting plenty of pics because if people don't have a basement they do have a crawlspace and if this works out for me i am sure there will be more people to follow. i will be taking plenty of pics once i get started just stay tuned in i will start with the pics sometime next week

humble yeah i know thats why im not gonna use drywall.

i think with the idea that the doc had about the water will work great with the weeping tiles and sump pump, also with the way i plan on building the room i hope to not have to worry about mold as the room is going to be air tight and all the air going into the room will be from in my house.

 

[HBxNLmaster]

here is a picture of how i plan do the water drainage and the basic layout of the hole

the red circle is the sump pump
the black line around is the weeping tile(4 inch pipe with hole in it)
the grey area around the pipe is gravel

i know this is crude and prob hard to understand but im not good at paint shop the gravel area is larger than actual but this is the general idea

 

[humble1]

what about the foundation? do you know how far it goes down?
i ask because if you're digging below the foundation you need to leave a 45 degree angle's worth of dirt from the bottom of the foundation to the bottom of your pit. otherwise the change in pressure could cause your foundation to buckle inward.