Dryer Venting Dilemma

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bhelm1

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I'm in the process of remodeling my laundry room due to a bad layout. I have moved the washer and dryer to a new location that is not on an exterior wall, it wasn't on an exterior wall before either. The old dryer location was vented into the garage but from what I read this isn't ideal. So I'm looking for ideas

I was thinking of running the vent down into the crawl space and under the master bed room and out the north wall but due to the direction of the joist I would have to use at least 4 90 degree turns to get below the joist system and then back up to vent outside and the total run would be something like 23'. I would prefer not to go vertically if at all possible.

Here is the new layout (washer/dryer are the 2 red squares):

House Rendering2.jpg
 
Gee, you don't leave many options ... Can't go under because the run is kinky and long ... Can't go vertically because??

You are stuck going kinda horizontally. I would suggest into the furnace/water heater room using smooth walled ducting to minimize resistance. Vent it to the porch.

VENT 1.jpg
 
If you do that build a box around it in tha garage and cover with drywall. Firestop and off gas protection.
 
I was wondering about running it out around the porch but wasn't sure if there were any problems with that being close to a door and porch overhang? Villa: Main reason I'm not wanting to go vertical is there are quite a few obstacles to get around/through and wasn't sure how good it was to go vertical anyway? In saying that I'm not completely ruling it out but looking for option. Here is a shot of the front porch area.

1415016555650.jpg
 
Ok. Porch is not enclosed as I imagined. CMV's plan should work and is a few feet shorter. Just be mindful of door clearance.

Vertical is not such a great idea. Lint gets pushed into the line but can't make the trip to the top You will have to clean it way too often.
 
Okay as far as running the vent into the crawlspace. What kind of setup works best, through the floor or into the wall cavity and then into the crawlspace?
 
Into the wall and down give you a better chance of pushing the dryer closer to the wall, but really it is whateverr works for the situation.
This is what they put in new houses now.
http://www.dryerbox.com/
It gives you a better chance of sealing things up and you do want fire proof caulk around your pipe at the floor and insulate it in the crawlspace. You want to keep it warm as long as possible so you don't get condensation in the pipe.
 
IMHO I personally want the run as short as possible and I want easy access to the full length of the run in such a way I can disassemble it and clean it out at least once a year. Mine I just set up went down about 2 feet and then across 2 feet to a basement window flapper vent. I can pull the elbow in the basement and clean both short runs from the basement. If it was a crawl space and any distance I know I would put off the job or maybe never do it.

Based on that I like Slownsteady’s route getting it away from the main door and being able to service it from the garage.
 
My house like everything in it was bass akaward they had the dryer vent on the left and the washer hook up on the right when facing it. Similar to the OP’s sketch. The problem with that in tight quarters is the way dryer doors open. If you are right handed I like to stand in front of the washer and reach down and grab stuff and throw it straight in the dryer without a door being there. I crisscrossed the lines and vents and plugs.
 
here is the code on a dryer vent distance and material

with 2 90 degree bends you can run a 4inch duct 14' total eachadded 90 bend deduct 2' from the length
a 6' flexible line is allowed to hook up the dryr uniform mechanical code

scan0001.jpg
 
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here is the code on a dryer vent distance and material

with 2 90 degree bends you can run a 4inch duct 14' total eachadded 90 bend deduct 2' from the length
a 6' flexible line is allowed to hook up the dryr uniform mechanical code

I think that is getting a little old. Now you add 5 ft for a 90* bend.
http://www.dryerbox.com/dryer_venting_guide.htm
 
do not understand your comment,

the UMC code says 14' with 2 90 degree bends and 6' fleex. that is max for a dryer vent.

if you add any 90 then you subtract 2' from the length per 90

the IRC

M1502.4.4.1 Specified length.
The maximum length of the exhaust duct shall be 35 feet (10 668 mm) from the connection to the transition duct from the dryer to the outlet terminal. Where fittings are used, the maximum length of the exhaust duct shall be reduced in accordance with Table M1502.4.4.1. The maximum length of the exhaust duct does not include the transition duct.

TABLE M1502.4.4.1 DRYER EXHAUST DUCT FITTING EQUIVALENT LENGTH

DRYER EXHAUST DUCT FITTING TYPE EQUIVALENT LENGTH
4 inch radius mitered 45 degree elbow 2 feet 6 inches
4 inch radius mitered 90 degree elbow 5 feet
6 inch radius smooth 45 degree elbow 1 foot
6 inch radius smooth 90 degree elbow 1 foot 9 inches
8 inch radius smooth 45 degree elbow 1 foot
8 inch radius smooth 90 degree elbow 1 foot 7 inches
10 inch radius smooth 45 degree elbow 9 inches
10 inch radius smooth 90 degree elbow 1 foot 6 inches

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 degree = 0.0175 rad.

M1502.4.4.2 Manufacturer’s instructions.
The size and maximum length of the exhaust duct shall be determined by the dryer manufacturer’s installation instructions. The code official shall be provided with a copy of the installation instructions for the make and model of the dryer at the concealment inspection. In the absence of fitting equivalent length calculations from the clothes dryer manufacturer, Table M1502.4.4.1 shall be used.



so, umc is giving you 14' with 2 90's
the irc gives you 35' but you must subtract 5' per 90.
35'-2-90's is 10' = 25' of 4" duct

transition duct not to exceed 8" not to be concealed
 
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That's the length of the corner. The code they use up here allows "I think" 30 or 35 ft of straight run and subtract 5 ft for a 90 as that's how much the air slows down or something.
 
I'm going to try to tackle this tomorrow. I'm going the garage route, I like the idea of have a garage access for clean out and it gets it a little ways away from the front door. Straight shot after i go under the floor brings me out about 12 inches from ground level to where the vent will be coming out of the garage wall. Is this acceptable or is it recommended to have the vent higher? I can move the vent higher but I would have to add another 90. Adding that 90 would put me at 3 total and my total vent run from the laundry room floor to garage wall would be around 9-10 feet.
 
the reason to keep dryer vents as short as possible is a due to fire hazards
the longer the run, the more chance of the lint not discharging, clogging the vent and catching fire

i dont use flex connectors, if i can get to the back of the dryer. hard pipe it
 
I think that is getting a little old. Now you add 5 ft for a 90* bend.
http://www.dryerbox.com/dryer_venting_guide.htm



Neal, dude I am so friggen slow. i swear fo God, I just NOW figured out what you meant in that thread. I must be getting old.

you had me completely baffled by the sentence that is getting a little old.
you meant the code i cited is old code. jezzzzzzzzzzz.
 
Neal, dude I am so friggen slow. i swear fo God, I just NOW figured out what you meant in that thread. I must be getting old.

you had me completely baffled by the sentence that is getting a little old.
you meant the code i cited is old code. jezzzzzzzzzzz.

It shouldn't have that hard to figure out, I typed it really slowly:D
 
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