Cape Cod Barn

[bebster]

Well, I took the advice here and waited on pouring the foundation. A couple of warmer weeks and the soil is now unfrozen (of course today we have a few new inches of snow, but it's March and it will be gone in a few days). So we'll start pouring the footings hopefully next week.

I'm planning on waterproofing the outside of the foundation using a Bituthane product, like shown on drawing attached. Does anyone have any experience with this or other products? I'm on a grade and want to insure that I don't get water flowing down and against my basement wall and then get a damp basement situation as a result.

 

[tc35dforme]

bebster,

With the sand, do you think you'll have water travelling horizontally. I've got hardpan clay at -6' and it stops the water dead. The water flows sideways all the way to the pond !! When you cut a trench, you see the flow layer and the waterjust perks into the trench from the sides.

 

[bebster]

I've got medium sand all the way to the bottom, but this year the soil froze in thaw layers, and I'm concerned that frozen soil will behave like clay and stop water against the foundation wall. I want that water to have a place to run and if it doesn't run anywhere fast I don't want it to find it's way through the concrete. You can see where I might get some water running into the foundation from the hill in the back right of this photo, and that's the corner that particularly concerns me.

 

[tc35dforme]

Its definetly best to do it now...I did just mop on mastic with a super deluxe perimeter drain system that flows to an open drain. All of my backfill was material with excellent drainage ( no organics ). Its easier for the water to drain down and run out the drain than to push through 10" of concrete.My basement is DRY /forums/images/graemlins/grin.gif

Recently I've see several projects where they use a corrigated plastic material that is pushed into the wet mastic. It comes in rolls. Its not a membrane, just a spacer. This stuff supposedly channels the drain water right to the drain tile and out. Anything you do to make the water get to the drain is good. Remember water is like most people..takes the path of least resistance.

 

[Junkman]

Put drainage pipe in the inside under the floor that runs around the perimeter and on the outside perimeter also. Connect the two drainage pipes together by running a pipe between the two through the footing and then run a line to a low spot far enough away from the building that it will not run back toward the building. I would make two connections of the perimeter drains on each wall all around the building for a total of 8 connections going through the footing. I did this on my basement and I have a totally dry basement no matter how much rain we have at any time of the year. It will not weaken the footing and it doesn't have to be exactly level all around. You just want to remove the water before it gets high enough to enter the building and a 4" perforated pipe will do just that. If you are concerned that the pipe will fill with sand, gravel, stone, etc., I have seen at Lowe's, a sock that you slip over the 4" PVC that allows water to flow through it, but will keep out fines. I believe that it cost about $20 - $30 for a 100' piece. I have seen my pipe running water when I least expect it.... a week after a rain storm when I think the ground is dry, but the water is still running underground. This is the least expensive method that I know of.
After reading this, I realized that I didn't explain how to get through the footing. Have the foundation company put 6" pieces of PVC in to the footing where you want the holes to be. Then when you put in the drains, you have the holes in the correct place. You caulk the holes with some Secrete when you are done with the footing drains. The 6" PVC is held in place by hanging it from nails. The foundation company is familiar with the procedure. It will be up to you to procure the PVC. Go to a place that sells PVC commercially and they will usually have a pile of damaged pieces. Usually they will either give or sell you scraps. I have gotten lots of them in lots of sizes for free. Even if you have to go to a plumbing supply house to buy a piece, it won't cost that much. If you have a saws all, that is the best way to cut it. Try your best to make a square cut, by first marking it with a felt tip marker. I am sure that someone here will give you tips on that. I use a miter saw. If I can get my scanner working I will post the picture of my footing from 20+ years ago...

 

[Junkman]

I just noticed in the drawing that you have as an attachment that there is a "membrane" between the footing and the wall. In my opinion, I believe that this is a mistake and that the concrete should be poured, concrete to concrete. Or should I say that the concrete wall should be poured with the concrete being in contact with the concrete footing and contacting the key-way. Anyway you want to put it, I don't think it is a wise move to separate the two concrete pours by a membrane.

 

[bebster]

Junkman, I noticed that membrane in the keyway too -- didn't make much sense to me, and I agree it should be avoided.
I get your concept about the interior/exterior drainpipes. I was planning on doing that on the exterior (with filter fabric like you suggested), with a vapor barrier under the slab on the interior. Why do you think you'd need a 4" perforated pipe on the inside of the footing?

 

[Junkman]

the reason for the drain on the inside is if for some strange reason a spring suddenly decides that it wants to form under the slab it has some place to drain to. It is cheap insurance for the unlikely event that water should pool under there. You have to realize that water can rise under the slab under certain conditions and you want to take it away. Just don't make the mistake of putting a floor drain into the floor. It is a great way for water to get on top of the floor during flood conditions.

 

[tc35dforme]

I did the underslab drain too ! Didn't cost but a few bucks and you never know. Just keep the two discharge pipes separate and DON'T connect the downspout drain to the same pipe !!!My concern was the hardpan. You will probably be okay, but if you get one of the high 'moon' tides /forums/images/graemlins/grin.gif

I'll be in your neighborfhood in July, I expect to see a big barn on the horizon !!

 

[bebster]

The interior drain is something that no one around here seems to ever do. I think it's because we have sandy soil and there are no springs -- just sea level tidal pools, and I'm 30+ feet above sea level. Everything drains really well.

I am currently planning to put 6" of gravel under the slab covered by clean sand, and then Insultarp, which is an R10 vapor barrier. I'm going to run some radiant pex tubing in the slab so I can keep the basement at 40 or 45 degrees during the winter to keep the vehicles from freezing. Should be pretty energy efficient given the average outside temperatures are usually in the 30's during the winter, and most of the basement is underground. I'm figuring that if I can keep the exterior water out (that comes doesn from the grade) that I"ll be fine.

But then again, interior pipe seems like cheap insurance. If I run interior pipe, should I run it along side the footing like I do on the exterior? I'm also a little concerned that pouring a 4" slab over this pipe might not be as solid of a subsurface as would be compacted gravel/sand. Have you seen any evidence of cracking above this inside perimeter pipe?