First of all, I don't have much knowledge about plumbing, but am eager to learn and tackle it myself before I have the pros come in.
Here's my problem.
When I first bought the house, the washer will drain, and I will see some soap bubbles coming up from the floor drain.
I always thought that I have put in too much soap, I tend to do that a lot. I'm a bit of an as obsessive compulsive person.
But after 14 months in the house, well, for the last 2-3 months, I realize water would start draining from the washer, and very soon, water starts to back up from the floor drain. It looks like water is not draining as fast as it should, and overflowing back up into the floor drain whole.
Now, dishwasher and kitchen sink, goes into the same drain stack, and have no problem draining. Is it just because of the volume of water being dumped out is way smaller than my washer? And if there is a clog somewhere?
Do I need to use a snake? Where do I put the snake in? Can I do it from the floor drain? Or from the main stack? I see this little cap that I think can be removed with a wrench right before the basement floor, is that what's being referred to as the stairwell trap? Is stairwell the "drain stack"(according to my zero plumbing terminology knowledge?)
Eager for suggestions. Thanks.

Hey plumber, You have enough knowledge to analyze your problem correctly. You have a partial blockage downstream from the floor drain. The reason that the backups only occur durning a washer discharge is that your sink "drains" with a low volume of water while a washer "pumps" out a high volume of water at great pressure. Your blockage consists of grease from the sink mixed with fibers from the washer. It gets worse if you have a disposal unit. You will have to snake out and flush the line. We snake out from the washer or kitchen sink vent stack on the roof. However if you have a two story house it may be easier to go in through the floor drain. However there's a tradeoff here. To snake from the flor drain means working the cable past the "P" trap in the floor drain which means that every foot you run out will have to be worked past the trap. Go on the roof or stay on the ground? Your choice. The "little cap" you refer to sounds like a clean out plug. The only problem with that is that if it's downstream from the blockage that you'll never hit it. You mention going down the main stack but the blockage is in a branch and not the main. If it were in the main then nothing would drain. So there's your options. I hope this answers your questions but if you have more just click on back. Cheers, Tom

Wow, Tom, you are amazing! Knowledgeable that's a given, but the speed of your reply!

I have a few more questions.

The "p" trap that you are referring to, is that close to where the floor drain? Or is it hidden from the horizontal floor drain into the vertical vent stack?
I see two holes in on the floor drain, one is straight down, it's not deep, then on the side it has another hole, but also easily accessible is the bigger hole on the side of the floor drain, all the water eventually goes to the one on the side, that's what I assume I'd put my snake into. Gosh, not knowing the terms really make explanation by words difficult. The "P" trap, is that what you're talking about the from the shallow hole into the other whole. I'm amusing myself now! What I see is there is a hole on the bottom that has a smaller hole that lead into the horizontal drain. Also, easily accessible, is the hole on the side, before the shallow hole on the bottom, and if that's easily accessible, does that take away the "P" trap difficulty? Or is t he "P" trap elsewhere I can't see?

Then, if I were to have to do it from the roof, how long a snake do I need? I'm just planning on getting one from the hardware store to tackle it from the floor drain. But even that, how long is enough?

And the clean out plug, the location of the plug is above basement floor level. I can see the pipes for the sink, dishwasher, and laundry washer above the clean out plug. Pretty much, the vent stack, and the washer branches and sink branches coming into the stack from top, then, the clean out plug, then the floor. With my limited knowledge, I only assume that the clog is below (downstream from) the plug. Is that not always the case?

"Snake out and flush the line" what does "snake out" do. When I put in the cable and turn it around, am I breaking the blockage, then run big volume of water, like my washer to flush it out ("flush the line")? Do I get this right? Snake out don't mean that I'd have to pull the blockage out from the drain, does it? It'd be rather "scary" if I have to face those clogs!

Eager to hear back from you. And I will post another plumbing problem in my cement cast shower pan that we inherited from the previous owner. That's another problem. But one at a time. Thanks a bunch Tom.

OK!  Let's get a few terms straight.   To "snake out and flush" the line simply means to run the cable in, break up the blockage and flush it out into the street main by cycling the washer.  The floor drain "P" trap is built into the floor drain itself.  Think of a "P" trap like his.  Take a P.  (Wait a minute! That didn't come out right)  Any how turn that P over so the flat line is on top and the curved part is on the bottom and now remove the line between the curved part.  That's what a "P" trap looks like.  The line that looks straight up is the hole that goes straight down in the floor drain,the trap is the curved part and the other line discharges out into the sewer..  You may not have to go up on the roof OR try to work the cable around the bend of the trap.  If there is a hole in the floor drain other then the one that faces straight down, (and this hole should have a cap/plug so prevent sewer gas from escaping) then that's a floor drain clean out.  Run your cable out through there.  You will have a straight shot all the way.   10 to 20 feet of  snake should do it.  I can't visualize the other clean out that you speak of but if you can run throngh the floor drain that's the way to go.  More questions?  I'm as close as a click.  Tom

Okay, I have ran the snake through the clean out plug. I felt some soft clog. I know I was hitting something. Then the snake stopped at around 20' and it stopped, that's when I started the clockwise twisting. Then suddenly it went through again, I'm assuming I'm hitting the point of the drain going to the vent. Now again, I am basing this on what I've learned in one day, plus some Home Depot Home Improvement book.
Since I'm a designer, it's easier for me to show you the diagram of what I did.
The result is good. I have to say that, the water is now running better. It has gone back to almost like a year ago. I load up a maximum load of water (only water, no clothes), and drain it (hot water), and this time, the basement drain hole only had some water overflowing. I was hoping that it would go away completely, but it is way better than the past few months. We've been having the finished basement's carpet wet every time we run a load of laundry.
It definitely worked.

But to follow up on how to make it entirely go away. I'd like to ask you for more suggestions.

I have been using some gel type liquid clog remover type thing twice after I ran the snake through. I don't know if you'd suggest perhaps running the snake again? Do I have to turn the snake every once in a while or do I just keep feeding until I encounter a corner, then I'll turn to get the snake into the turning point?
Ideally, I'd like to see the water not coming up to the basement floor at all. But even with this condition, it is still way better than this morning.

Please give me further advise. I really appreciate your help.

And here's a diagram of what I did.

http://johnong.com/albums/etc/Drain.gif

Good morning John, By your diagram I see your house is a one story with a basement. I wish that you had added dimensions to your print so I would have some idea of where the cable was 20' out, (all you need to snake is the branch line you know). You ask how to completely clear the line. First off, I am no fan of using harsh chemicals to clear a blockage. To make a drain smell sweet and to loosen grease I recommend 1/2 gallon of bleach to loosen followed by a few large pans of boiling water to flush the line. OK! So you got through the blockage, however you just poked a hole through it. You just pushed the cable through and augered only when you felt resistance. What kind of a tip did you use on the end of the cable. If it was a auger,( screw type) tip, change it for a spade tip. Now commence auguring, (turning) that cable as it works its way through the branch. The spade tip will strike and clean the pipe walls as it twists. But it must be turning as you proceed forward to be effective. Now flush out the line by cycling the washer and let me know how you make out. Tom

Cool. I'll take your advice on the bleach and boiling water solution.
I have finally heard from a pro telling me not to use the chemicals. Well, I haven't spoken to anyone who really knows what they're talking about other than you. All the other advice I got from people like me or even those who seems to know more about me asked me to use the chemicals.

Okay, I went and bought a $12 snake (3/8"x25'). From the price, you probably know that it is the one long wire cable type of snake. It doesn't have the canister to hold it. When it's clean, it's okay, but when it been used, it's a bit messy. But when I retrieve back the cable, I wipe it section by section as it's coming out from the clean out entrance.

As far as the tip, it is not changeable. It's the kind that's on most cheap snake. The one that sort of ballon out wire.

Would I have much luck if I auger it as I'm going in, just with that kind of a head. Or should I go out and buy one that has the replacable head? Do they sell any that does that? I would mind spending more if it's going to solve the problem, but not a few hundreds though. I thought after reading your last post, I was looking around. And I seems to have found the brand Cobra. And they might have inexpensive, like around $30 for a canister that you hook up to your hand drill. And possibily having replacable heads too. The spake you're talking about, is it the kind that looks like a U or Y that are blades, for cutting through roots? Or is there something else.

Can you suggest a specific kind, or brand? Or have a picture, so I'd know what to ask for in a store. Or perhaps, I can just go to a hardware store and ask for a snake/auger with a spade head?

Thanks a lot. Can't wait to move to the next step.

A spade tip looks exactly like the spade on your playing cards.  Its function is to scour that insides of the pipe and break up whatever remains.  You have broke through the blockage.  What's left is to get the rest of it out.   Changeable tips come with a comercial sewer machine such as a Ridgid K-60 or 50.  However don't go out and spend big bucks for something you may not need.  Back in the old days when there were no sewer snakes we had flat metal "rods" made of spring steel  with a ball on the end  that we rolled up to transport.  The balls would punch through the blockage Ok but wouldn't scour and clean the pipe out.  How we got around this was to attach heavy wires a little bigger then the pipe we were rodding to the ball until the end looked something like a porcupine.  The wires would scour and remove the rest of the blockage.  Now we couldn't rotate the tape so we had to put quite a few wires on to hit the walls.  However you can crank and rotate the cable,( you DO have a crank on your snake don't you?) you have so 4 or 5 wires looped around the cable so that the end of each wire will touch both sides of the pipe wall should do you just fine.   You have got the worst out.  Now all you have is the clean up.  Kudos for sticking with it and saving you big bucks on a service call.   Let me know how it all comes out,  Tom