Sewers

Plumbing: Does a drain for a bathroom sink have to approach from the back of the sink?

OR can I re-route the drain to enter from the side? My bathroom sink is located in a corner with the back to an outside wall. The builders installed the the drain pipe to come up through an interior wall to the right hand side and turn the corner 90 degrees to get into the outside wall so that the drain could approach the sink from the back. This sink clogs constantly due to all the angles - I have to remove the trap and clean the pipe in the wall every four months and the smell from the pipe clog is horrible, like straight sewer gas. I would like to know that if I tear off the drywall and route the drain to come from the interior wall straight to the drain, to remove the 90 degree turn in the outside wall, if it would still meet code? http://img406.imageshack.us/img406/464/sinkrf2.jpg In the picture the Pink represents the CURRENT drain and the white tape represents what I want to do. the house was built in 1979 and I don't know what they were thinking when they did this.

Public Comments

1. That looks fine. Doesn't mater which direction it drains as long as it drains "down".
2. No reason I can see why that wouldn't work. But to be sure you will have to open up to see if they had a reason - they sure created more work for themselves. Either there is something strange in your building code or they approached it from behind because, "That's the way we always do it."
3. the clog may be cost by hair accumulations ,try to add first some chemical to dissolve, you can buy it from any hardware store. ya I agree with your new design ( the white line ) since it is shorter and going to save one elbow .
4. you could switch it but there is no good reason for it to clog much now, unless there are some restrictions or there is not enough drop after it enters the wall or you are putting stuff in it that doesn't belong. it is unlikely the layout is the problem
5. everything you mentioned so far will work the only variable I can't see is the vent. all plumbing fixtures must be vented in order to work properly ( not glug) if when you remove the drywall from the wall there is a "t" fitting you would have to reconnect to the pipe that is going up, as well as the new access in order to have a vent. another solution is to put a clean out somewhere near where it clogs that would make it easy to unscrew a cap and shove a small snake down to unclog your sink without disconnecting everything.
6. The plumber used pressure fittings to make the tight turns. Drains have to plumbed DWV fittings which have a wider radius. They take a up a larger space. That's why the plumber used the pressure 90 to make a tight turns in the walls.
7. I cant see any problem with it you will be eliminating two bends makes sense to me. One bit of advise when you reroute use a sweep(long turn) ell to connect to the down pipe no sharp turns.
8. You can drain it any way you like. Why not look into draining it straight down through the floor. and connecting into the main drain below. Many houses drain down under the floor. The faster the drop, the better the drain. As far as the sewer gas smell, you are right, you do smell the sewer. Traps are made to block the sewer smell by using trapped water as the smell barrier, which is why traps are so important. Drains don't usually clog up even when they travel horizontal for long times unless something is put down the drain to block the flow. It sounds as though hair or something else is causing the problem and might need to be addressed. If you still want to reroute the drain you can. the drain is 1 1/2 pvc.
9. And the winner is; The vent Must be reconnected and if you run the pipe the way you want to the vent will be gathering waste. The easy button is to treat your drain once a week and avoid putting grease into it.