The Mystery of the Moving Conduit

[Chas]

I have had hundreds of folks try to put the electrical conduit in the slab. Dozens and dozens of them have tried to hit the exact spot where the power comes into the spa so nothing shows.

About four have actually hit the mark.  


I just wanted to start a thread that might be helpful for others pondering this same concept.

Here's the mystery: you can measure the tub, you can use the dimensions given by the factory, you can even beg the dealer to tell you where to put the conduit - I won't do so, but some dealers might. However you get the dimensions, you can then put in the conduit, or have your contractor put in the conduit locating it at exactly the right spot.

Whatever method you use, chances are that by the time the concrete hardens, your conduit will not be in the right spot. Here are some of the methods I have seen our customers use in failed attempts:

1. simply put it in themselves, and drive a big stake next to the conduit. I'm talking huge stake. So large, in fact, that they end up having to chisel out the extra lump of concrete that ends up mounded next to said stake. Still doesn't end up in the right spot.

2. position the conduit, and cap it off just at the level of the finished surface. The plan here is that they can just break out a tiny bit of fresh concrete and extend the conduit up as needed. Not only does this still end up in the wrong place, but sometimes it ends up disappearing altogether. Not fun.

3. owner stands there and watches as the concrete is being poured and/or finished. He may even stretch out a tape now and then to assure the conduit is still in the right place. Still mysteriously doesn't end up in the right place, AND the owner ruins his favorite pants and/or shoes. If you do try this, pound in two stakes 90 degrees apart, for example, due north and due west. Put them exactly the same distance away from where the conduit is supposed to end up. Put the stakes completely out of the cement area - as an example, 10 feet north and 10 feet west, or 30 feet if you have to, but both the same.

That way you can run out now and then and simply measure the distance from the two stakes to the conduit. Not only does this make the measuring easy and quick, but theoretically you can’t accidentally swap the two measurements.  NOTE: this, of course, STILL doesn't work, but you will be far more amazed[/i] and upset when it doesn't.

4. electrician puts in the conduit and leaves, concrete guy puts in the slab and leaves, conduit is wrong and the two contractors stand there and blame each other for doing something wrong. Owner shoots both contractors and ends up in prison where you DON"T want to get into a hot tub in the highly unlikely event that they have one.

There are so many steps in pouring concrete that can move a conduit: the general digging and leveling, spreading out sand and/ or gravel if used, positioning of welded wire mesh if used, positioning of rebar if used dragging around the huge hose if a pump is used, running it over with a wheelbarrow if a pump is NOT used, stomping on it with large boots if the slab is big enough for the guys to have to walk in the wet mud as they work, and of course, my all-time favorite: the Bermuda triangle effect.

How to hit it every time?  

1. put the conduit into an 18" boxed opening in the slab so you can fine-tune the end of the conduit and perhaps even locate a drain in the hole. You can then fill and finish the hole once you have the spa on site and the exact location is much easier to control, or you may just fill the hole with gravel or even leave it open if most of it ends up under the tub anyway.

2.  put the spa in, mark the spot, move the spa a few inches, drill a hole in the nice new slab, and then tunnel to that hole and connect up. This is MUCH easier than it sounds, but realistically can only be done if the conduit hole is going to end up less than about four feet from the edge of the slab.

3. put your spa on a wood deck.

[hottub.pool_boy]

a good piece, I like the 18" opening idea.

Went to deliver a grandee last week, found 1.5" conduit sticking up through pavers. Chisel woodkick plate, repaint with some flat black, heat gun the rest for the door to fit. An extra trip for a total of two hours.

No one asked, no one called. I heard " I thought/ I figured", but no, I did not call to ask what size I should have used. We had already said 3/4"-1" conduit, no one was listening.

[salesdvl]

.... no one was listening.

I'm sorry, did you say something?  

[Vanguard]

As I was reading your post, Chas, I was thinking about my own experience trying this.  I did it when I was building a house.  They were to pour the tub slab at the same time as the house slab.  

I marked EXACTLY where I wanted the conduit to come up.  When I checked, the guy who did the line had ignored my stake - still in the ground by the way - and put it where he wanted.  Luckily, the slab had not been poured, so I simply moved the conduit to the correct position.

So we go through the house building process and finally move in and have my spa delivered.  As I am setting the spa down, I find the conduit is not  where I thought it would be.  Luckily, it did not move very far, so it was not a big deal.  The spa just was off a couple of inches.

So my builder comes by for a checkup on the house and I tell him about the conduit.  He says, "Yeah, concrete tends to move stuff as it cures.  That's why we use the big black pots for things like toilet lines and bathtub drains."  

You thought he could have mentioned that.  The black pots were flower pots turned upside down to allow exactly what you're describing.  That is a great way to do it.  

I'd use gravel to fill the left over hole because it can act as a drain if your slab isn't level.  Not sure if that's a good idea or not.  But it sounds like it may be.

[mattNY]

NOTE: this, of course, STILL doesn't work, but you will be far more amazed[/i] and upset when it doesn't.

Lol, that is the best part.  

[Bill_Stevenson]

I had to laugh reading this thread.  As per usual, Chas is right on.  I was lucky in that instead of a slab, we used pavers at our new house.  The builder got it wrong anyway and it all had to be dug up and re-done.  Atta-boy Chas, keep up the good work.

Bill

[TN__HOT_TUB]

We ended up running the conduit right along the base of our tub.  We have about 18 inches of flexible conduit showing.  It doesn't look bad.  We're planning on extending our deck to cover it.

If i were to pour the concrete over the coduit, I'd use the bucket/box method and back fill it with gravel/sand.

[ndabunka]

When you poor concrete you usually (always?) have boards on the outside that retain the concrete until it hardens, right?  What I did was simply to attach metal brackets to the two boards that formed the corner and then ran the conduit through the opening at the end of the metal strips.  I think the strips/brackets were something like $3 each @ Home depot. Maybe I missed something at the time I did mine but it really didn't seem like a big deal. Hard part was helping the guy pour the concrete (his help bailed out on him so I ended up doing about half the job) but the price was right.

[Chas]

So you put the conduit off in the corner of the slab? Did it come directly up into the spa?

[Drewski]

Sorry Chas, BUT

#4 -- Go up to WalMart and buy some cheap boxes and packing tape. Go to the dealer and ask them to put the spa up on it's side. Cut up the cardboard and then tape the pieces together to make a matching pattern that EXACTLY conforms to the bottom of the spa. Cut a hole in the cardboard where the conduit will come through. Cut the pattern in half or quarters & tape so you can fold it (easy for transport).  Make your form, lay your wire and  place your conduit using the cardboard pattern.

Works like a charm, I'm 4/4 with this method....

Drewski

[drewstar]

I'd think spa dealers could supply a template for the base of the tub with the place for the electrical clearly marked. No?

[Tatooed_Lady]

I'd think spa dealers could supply a template for the base of the tub with the place for the electrical clearly marked. No?

Sure! For an extra $49.95 + $83/hr labor (minimum 3 hours labor charged) + $87.49 materials..........  

[drewstar]

Sure! For an extra $49.95 + $83/hr labor (minimum 3 hours labor charged) + $87.49 materials..........  

Huh?  I'm talking about a paper the exact size of the spa base that the home owner could lay down on the pad area and mark it off.  

Cost should be $.99    

[Drewski]

Unfortunately, paper dosn't work well, I tried THAT the first time. It blew around in the wind and tore.

As far as the dealer providing it, I'm thinking they would then incur a liability issue so they avoid it. I could hear it now:

"But I followed your template EXACTLY and it's STILL in the wrong place... YOU need to pay for it!"

Drewski

[Chas]

Sorry Chas, BUT

#4 -- Go up to WalMart and buy some cheap boxes and packing tape. Go to the dealer and ask them to put the spa up on it's side. Cut up the cardboard and then tape the pieces together to make a matching pattern that EXACTLY conforms to the bottom of the spa. Cut a hole in the cardboard where the conduit will come through. Cut the pattern in half or quarters & tape so you can fold it (easy for transport).  Make your form, lay your wire and  place your conduit using the cardboard pattern.

Works like a charm, I'm 4/4 with this method....

Drewski

 

Nope. Don't believe a word of it. Your conduit moved, you just got lucky that the Bermuda Triangle Effect accidently pushed it right back where it belonged. BEWARE - you won't make it happen next time!!!

In fact, you most likely had the template upside down and if the conduit HADN"T moved you would have been in trouble.

Take care...