Run dryer vent behind washer?

aaroncgi · Thu Mar 01, 2012 6:34 pm

Hi all. I have needed to redo our dryer vent for a long time and am finally getting around to it. It was just a mishmash of the semi-rigid flexible aluminum with all kind of kinks and crushes, not good. I want it to be as much rigid smooth wall pipe as possible.

I believe I'm just overthinking trying to make it work using the existing setup. Currently the vent goes through the floor vertically behind the dryer (but not centered on the dryer exhaust!), makes a 90 degree turn then out the skirt. It's all the semi-rigid duct. And, it comes out under our deck, which although low, I think still has barely enough clearance, but doesn't really allow access to easily clean the duct (or install a new hood for that matter). Also, since I don't want to use any flexible section, I really can't come up with an easy way to attach the dryer unless I want to move the washer every time I want to move the dryer. I suppose that's workable, but still has three elbows.

So I thought, why go through the crawlspace at all? Why not just run directly out the sidewall with a brand new hole in the wall 2-3' feet above the deck? This would cut the number of 90 degree elbows from three or four to one or two, and reduce total straight length significantly. The only issue is, our washer is on the left/outside wall, our dryer is on the right. We can't swap the positions because the doors cannot be reversed on either machine. If there's enough space behind the washer and no obstructions as far as water line/connections, is there any reason a solid dryer duct cannot run behind the washing machine? We have about 6" of clearance behind the machines.

My thinking is to install a 90 degree elbow off the dryer exhaust going straight up 2-3', then another 90 degree elbow going left and then about 4' to the outside wall. This way, I could easily reach behind the dryer to disconnect the vertical section from the horizontal and move the dryer out if needed, plus cleaning couldn't be simpler. I could do it with two 45 elbows and run the pipe at an angle, which is even better, but that would leave no way to detach the dryer without moving the washer all the way out.

Greg · Thu Mar 01, 2012 8:00 pm

That will work, However I can tell you from experience you WILL have a problem attaching the vent to the back of the dryer. It is next to impossible to attach a rigid pipe by sliding the dryer on to it. I ended up putting ours onto a pedestal so I could reach under the dryer to guide the tube in place.

Greg

aaroncgi · Thu Mar 01, 2012 10:32 pm

Greg,

Thanks for the response. Actually my plan was to affix the 90 degree elbow at the dryer outlet and a vertical length of straight pipe above, before pushing the dryer back. Then once the dryer is in place, I'd attach the final 90 degree elbow to transition to the pipe going through the wall. I want to avoid exactly what you describe, though your solution certainly is a valid one as well.

Studying the diagrams, manuals, and various guides on dryer venting makes one wonder how anyone follows the recommended procedure without being plastic man.

aaroncgi · Mon Mar 05, 2012 12:18 pm

My wife and I did this job in a few lazy hours yesterday, no problems at all. It turned out the exterior wall studs were in exactly the right spot to not be in our way for the 4" duct hole. We missed a stud on the left by about an inch, other side by a couple inches, sweet! Total straight duct is only 67", with a 90 degree elbow and a 60 degree elbow. We're really pumping out the hot air now! We had to move the units about 1" further into the room than expected, but no big deal there.

The hardest part of the job was finding new washer fill hoses with a right angle on them. These were remarkably difficult to find, especially if one wants the stainless braided type. I eventually had to just go with reinforced rubber hoses, so I'll just replace them a little more frequently.

mdnagel · Tue Mar 06, 2012 8:33 pm

Once again I'm impressed with Greg's suggestions/solutions. In case it didn't get properly digested, here's what he suggested:

Build a raised platform and route the ducting underneath the units. If you've got front-load units this would probably make things even better, as it would raise things up for better access.

My washer and dryer have reversible doors, which is really nice (any manufacturer that doesn't do this should be shot). But as is typical, there's ALWAYS some complicating issue- I wanted my dryer pushed over next to the washer so I could have a pocket area just inside the rear door for hanging coats and sowing (usually WET) boots; GAS PIPE! stupid duct had to wrap around the gas line, not to mention that the pipe stub coming out of the dryer (with attached line) tends to push stuff out more than I'd like (dyer manufacturer has a kit to port the exhaust out the side -GOOD- but it's on the wrong side -BAD!). Like I was saying...

My head is too crowded right now to fully appreciate you twists and turns, but I figured I'd note that there are rigid 90 degree "elbows," though I've heard that they don't really buy you that much space:

http://www.lowes.com/pd_84556-131-L3006 ... facetInfo=

And just a general note, be sure to clean dryer ducts once a year. These are one of the leading sources of house fires.

Greg · Tue Mar 06, 2012 8:39 pm

I had to build a platform, after doing a head stand behind the dryer to TRY to connect the vent It finally dawned on me that it would be a LOT easier to reach up from under the dryer to connect the pipe. AND you gain some more storage space too!!!

Greg

aaroncgi · Wed Mar 07, 2012 7:06 pm

mdnagel wrote:Once again I'm impressed with Greg's suggestions/solutions. In case it didn't get properly digested, here's what he suggested:

Build a raised platform and route the ducting underneath the units. If you've got front-load units this would probably make things even better, as it would raise things up for better access.

Indeed this is a great suggestion. We didn't opt for this route, because although we have front load units, the controls are on the top back like the old style top loading unit. Plus, we have shelving above the units, which really limited how far up we could have moved them. Also with our deck just an inch or two below the floor, we still would have had to go up at least a foot for proper clearance under the outside hood anyway, unless we wanted to go back through the crawlspace.

mdnagel wrote: My washer and dryer have reversible doors, which is really nice (any manufacturer that doesn't do this should be shot).

I totally agree. Our units are about nine years old, just as front loading washers were becoming popular. It think reversible doors are a lot more common now.

mdnagel wrote:
My head is too crowded right now to fully appreciate you twists and turns, but I figured I'd note that there are rigid 90 degree "elbows," though I've heard that they don't really buy you that much space:

http://www.lowes.com/pd_84556-131-L3006 ... facetInfo=

And just a general note, be sure to clean dryer ducts once a year. These are one of the leading sources of house fires.

I saw this kind of elbow at the store, but really only works when your duct is pointing the same direction as your dryer exhaust, just high up on the wall. In our case, the duct is at a 90 degree angle to the dryer exhaust. We did end up with all rigid elbows. We took the dryer out onto the deck to connect everything (limited space in the laundry room). We connected our two elbows with the 2' straight pipe in between and taped and clamped all joints. Then we added a 2.5' straight pipe to our hood's tail pipe, and finally pushed the dryer back and made the final connection which sits about 33" above the floor and right at the edge of the dryer, so it's easily accessible from the top or side if you want to slide the washer over a bit. The beauty of our connection is that it couldn't be simpler to take apart and clean. I've heard that an electric leaf blower can be used for that purpose, and we do have one of those.