Cape Cod Barn

[Junkman]

You run it parallel with the outside pipe and it doesn't have to be right against the footing. It also doesn't have to be any higher than you want it to be. I have never had any cracks in the floor and you have a greater chance of the floor cracking where it is sitting on the footing and the area that is over the compacted sand moving causing a crack that runs along the footing . Hope that I have explained this well enough. To elevate this from happening in my basement, I took a sledge hammer and broke the edge of the footing all along the edge all along the inside so there were no sharp edges. Didn't look pretty, but gave it a rounded edge for the floor to rest on. Floor contractor said it didn't matter, but it made me feel better. I also poured a thicker floor than you are. I went with a 6" floor. Concrete is cheap once the truck is there. The finish work cost the same. Spreading it out was almost the same also. Spend the extra $400 and add the extra inches.

 

[tc35dforme]

I did a tree pattern, a center main with several lateral branches out. The water will find the pipe /forums/images/graemlins/smirk.gif. I wasn't at all concerned with structural loading. The 4" doesn't create any real weakness when its below the slab.

You'll love the radiant. It's great to keep the slab dry when the cars come in all slushy. Just watch expansion joints. With a large slab you'll need to allow for the slab to swell when heat is on. You can do this by using the new foam type expansion joint material and high tech caulk. This is different than a control joint which is just a cut in the top third of the slab.

Get a good concrete floor crew. You need to be extra careful with the tubing. Protect the risers ( out of the slab ) with electrical PVC conduit ( long sweep elbows ), or better have them come into a boxed out area that will be filled later. Those whirlybird floats love to eat tubes.

Its critical that you get a good embedded job. If the tubing floats up a bit, you'll get a weak spot on the slab and it'll spall off. One trick is carefully tie off the tube to the 6x6 WWF re-inforcement. Then use SMALL blocks of foam insulation to support the mesh at the proper level. This usually only works well for small pours where it can be worked from the edges. Other than that, you need to pick and lift the mesh and hope the crew is good at it. Maybe two pours with an expansion joint in the middle ??

 

[bebster]

Thanks for the pointers on the slab. I'm a few months away from that, and will make sure we do this right. Junkman, you make a good point for the thicker slab. My current slab design varies from 8" to 4". 8" is the thickness at the edge of the garage door opening for extra beef there where the stress is high. The picture below shows that on top of my 4' deep frost wall and footing.

It then tapers back to 4", but I wanted to have some slope to the interior slab floor, so that water would drain out the garage door side (or melting snow on a vehicle), so I was planning on making the slab 1 1/2" thicker on the side farthest from the garage door.

I guess I could taper the slab back less, to say only 5" in the middle, and then thicken it to 6 1/2" on the far side for my drainage. That extra inch would give me a slab that ranges from 5" to 8" thick. Sounds like a good idea to do so.

 

[bebster]

Well today was an early spring day on Cape Cod -- it has been warm enough for the ground to become unfrozen and for the concrete pumper truck to show up to pump concrete into the barn's footings. Needed to use a pumper truck since there is no easy access to the far side of the barn. It took 2 full cement trucks about an hour to fill up the footings, which have a total perimeter length of about 170 feet by 3 feet wide, by 1 foot deep, all at least 4' below grade. But the job got completed finally by the end of the day. The guy on the top of the bank is controlling the boom with a joystick he's wearing on his belt, while the rest of the crew is placing the concrete and smoothing it out. More pictures soon.

 

[bebster]

Yesterday finally got the foundation walls poured. Took the crew a few days to form the walls and place the rebar (18" o.c. vertically and horizontally to reinforce the high wall). Here's a picture near the end of the pumping -- the 6th concrete truck in the background. Now we can move onto building the first floor deck on top of TJI joists. Only 2 weeks left before timber frame is due to arrive -- it's being hand cut in New Hampshire.

 

[Junkman]

It's getting smaller already! /forums/images/graemlins/grin.gifWhen is the party? /forums/images/graemlins/shocked.gif

 

[wroughtn_harv]

You have to be having more fun than a pup with two tails.

It's nice to see someone doing a project like this and not stopping by once a month to check progress.

 

[coopers]

Is that a JD 120 excavator in the background?

Blake
WA

 

[bebster]

Junkman, I'm just about ready to start putting in the 4" perforated drainage pipe. Am I correct that, on the outside perimeter, you connect the pipes with a right angle bend piece so that the lengths and widths of exterior drainage pipe become one connected system that then slopes out to daylight?

 

[Junkman]

That is correct.... did you provide for connecting them to the inside perimeter drains? I didn't see any provisions for a inside drainage system in the picture of the footings you posted, but I could have missed it.

 

[tc35dforme]

I'm not Junkman ( which I guess is a good thing !!!! /forums/images/graemlins/grin.gif ), but I did a loop and took a single common pipe to the outfall.
Just put the 'high' spot opposite the drain out. You don't need much slope, the water will be happy to take the easy way out.

 

[bebster]

I did not put in an inside perimeter drain yet. But I do have a special situation that I think will work fine, since my East basement wall is a driveout wall where 2 overhead doors will go. I've attached a drawing of the elevation of this wall. That wall is actually a "frost wall", and is 4' lower than the other 3 walls, and is 3' below the top of the slab.

My plan is to fill along the inside of that wall with some gravel for drainage, and to dig and fill some trenches under the slab with gravel too, and run those trenches to this wall. That way any water under the slab will drain to this low wall, and the gravel against the low wall will serve as a french drain pit that is 50' x 1' x 1' that would hold 50 cubic feet of water.

Once any water is there, the soil beneath the gravel is all sand, and perks really fast. So I'm confident that any water there would then drain into the sand below.

Since the soil here is sand, we have no springs in the area, just tidal flats (and I'm about 30' above sea level). Also I'm putting in a very good vapor barrier under the slab to prevent any moisture from below getting in. None of the basements in this area have ever seen water coming from below because of the sandy soil.

Bottom line I think this system will work just fine for my situation. It also has the benefit of not having any penetrations from under the slab to the outside that could in fact become a source of water coming back into the interior.

 

[bebster]

While the carpenters were putting on the sills on the new foundation wall, I decided it was time to dig the 40' trench from the well to the barn. Need to get it down at least 4' below the frost line. A little spooky getting close to the edge of the foundation hole. Glad I got the backhoe with the larger reach!

 

[Junkman]

I suggest that you set the line into a 3" or 4" PVC schedule 40 pipe so if it ever has to be replaced, it will be easier to do. If we have another winter like the past one, 4' might not be enough. I think that the ice age is returning to New England. /forums/images/graemlins/frown.gif

 

[bebster]

Finally got underway a few weeks ago as the weather turned to spring. Here's a photo of the footings being poured. Had to pump them because the access is not so great.

 

[djradz]

Nice work so far! One question, you're willing to set the footings on sand and you have sand, sand everywhere. The use of gravel/stone under the slab seems pointless. What is it you hope to achieve with it? If this was my project, I'd just have good drainage around the perimeter of the walls and keep natural runoff away from the building and set the slab on all that beautiful sand. You'll never have a problem.

 

[bebster]

Good points on the sand. I'll get to that on a subsequent post. Meanwhile, here's a photo of the walls being poured. The walls are almost 10' tall, so I can have a basement overhead door of 8'6" so my tractor can drive in and out without lowering the rops. Lots of rebar went into those walls.

 

[bebster]

Here's a photo of the barn foundation walls after the forms were removed. The well is above and I dug the 5' deep trench with my tractor, which you can see. The frost line in Mass. is about 4'. A little scary getting close to the edge, but I am happy that I have a BH with a larger reach.

 

[bebster]

We put 4" perforated pipe on top of 1 1/2" stone all around the footings. I also decided to add waterproofing to the foundation. Used a product from Henry Co. called "WP200 Blueskin". It's a tar-like membrane with a blue puncture-resistant covering that goes on over a green primer/sealer applied to the concrete. I then added 1/4" fan-fold insulation to further protect the membrane during backfilling (which is not too much of a problem because it's mostly sand). You can see that the wall on the drive-in side is 4' lower than the other walls.

 

[bebster]

I decided to backfill the low wall exterior wall (which is below the slab) with stone to create a french drain of sorts that is about 3' wide, 3' deep, and 55' long. This should catch any runoff from the higher foundation and let it perk into the sandy soil below. Since water takes the path of least resistance, this should be the path vs. trying to penetrate the waterproof membrane to get inside. Also the perforated pipes on the higher footings will be run to daylight on the down grade to further channel water away from the foundation. (that's a JD 160 excavator doing the work by the way)