# ok to vent dryer into crawl space under house?



## merk (Feb 1, 2016)

We're having the washer and dryer moved in our garage. They are being put in the front corner of the garage. The vent for the dryer will either be on the front of the house - front of the garage technically. Or they mentioned they might try having it vent under the house into the crawl space under the house.

Is there any issue with doing that? This is in the San Francisco area.


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## slownsteady (Feb 1, 2016)

A lot of moisture comes out of that little pipe. Are you sure you want that under the house???


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## merk (Feb 1, 2016)

slownsteady said:


> A lot of moisture comes out of that little pipe. Are you sure you want that under the house???


no, i'm not sure, that's why I was asking


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## havasu (Feb 1, 2016)

You really don't want all that moisture down there. You need to vent that moisture outside, where it belongs.


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## merk (Feb 1, 2016)

havasu said:


> You really don't want all that moisture down there. You need to vent that moisture outside, where it belongs.


thats what I was thinking - the only reason i can think of for not doing that is it avoids having to poke a hole in the front of the garage, but venting all that moisture under the house didn't seem like it would be a great idea.


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## nealtw (Feb 1, 2016)

Or did *THEY*mean they were going under the house and out somewhere else like the far side. If it is going some distance make sure it is insulated.


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## KULTULZ (Feb 2, 2016)

nealtw said:


> Or did *THEY*mean they were going under the house and out somewhere else like the far side. If it is going some distance make sure it is insulated.


 
And, depending on the length of the run, whether the dryer is rated to push that far or a booster fan will be needed and, lint accumulation will be problematic.


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## frodo (Feb 2, 2016)

15' and 1 90 is all your allowed for a dryer vent

and do not use screws on the duct work to put it together or to hang it, use tape only


feel free to put the dryer vent termination any where that you would also put a garden hose with a sprinkler head on it.

basicly,  it is the same thing,


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## merk (Feb 2, 2016)

frodo said:


> 15' and 1 90 is all your allowed for a dryer vent
> 
> and do not use screws on the duct work to put it together or to hang it, use tape only
> 
> feel free to put the dryer vent termination any where that you would also put a garden hose with a sprinkler head on it.



15 feet length? what is 1 90?

actually, i'm not even sure if the crawl space extends under the garage or not. Seems like the garage, which has to hold a car up, might just be solid ground underneath, no?

The most physically convenient place to put the vent would be on the front of the garage since the dryer will be sitting right up against that wall. The most aesthetically pleasing place would be on the side, which is probably about 8 feet away, directly. If they can run it under and then have it come up the side that would be nice. 

Bottom line - i'll check with them tomorrow to see if they can/are going to run it underneath and to make sure it's venting outside somewhere, otherwise they can just put the vent on the front of the garage.


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## nealtw (Feb 2, 2016)

They won't be going under the garage floor, when you said crawlspace we thought the crawlspace under the house was close by. If they can get to the crawlspace they can run thru it, but don't let them run into it and dump the air in it. I think the limit is 20 ft and each 90* bend is the same as five feet of run so with one 90* bend you can have 15 ft. or 2 bends with a total of 10 ft or something like that.
The problem with long runs is the work the fan has to do and the fact that the air inside will cool and water will condense in the pipe.
Some one will correct my allowances on the pipe length, but that is the just of it.


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## nealtw (Feb 2, 2016)

I just borrowed this 
The maximum length of a clothes dryer exhaust duct shall not exceed 25 feet (7,620 mm) from the dryer location to the wall or roof termination. The maximum length of the duct shall be reduced 2.5 feet (762 mm) for each 45-degree (0.8 rad) bend, and 5 feet (1,524 mm) for each 90-degree (1.6 rad) bend.


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## merk (Feb 2, 2016)

ah ok, that makes sense. i think the only way they could vent it out the side of the garage is if they run the pipe/hose up the top of the garage and then make a vent on the top side of the garage. That would be 1 or 2 90 degree bends. i think though given the quality of work these guys have done so far, my best bet is the simplest/easiest/most direct, which be to just have them vent it out the front.


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## Sparky617 (Feb 2, 2016)

How obnoxious will it be to have the dryer vent in the front of the house?  Won't it be covered by landscaping?  Long runs can be problematic for dryer runs.  It can be compensated with booster fans, but that adds another layer of complexity to the system.  

I had a dryer vent in the front of my second townhouse.  You really couldn't see it from the street or the yard.  It was visible when you came up to the front door, but it wasn't the only utility item in that area.  At least on this house they managed to put the gas and electric meter on the back of the house.  My first townhouse had the electric meter right on the front, it was my piece of Met-Ed artwork on the front of the house.  Landscaping eventually camouflaged it.   That house had a run that was probably 20+ feet long with at least one 90 degree bend in the ceiling.  It worked ok while I was there, I have no idea if it caused a problem for any of the subsequent owners.  I only owned it with that configuration for a couple of years.   I did run it in rigid pipe without any screws holding the sections together, just aluminum duct tape.  Screws will catch lint that makes it through the dryer filter and eventually clog the dryer vent pipe.


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## frodo (Feb 2, 2016)

the fan wont push the lent out of the long pipe.

it will clog the pipe and reduce efficiency of the dryer and be a fire hazard. 

Neal is correct,  it will also let water accumulate

found an extra 6' for you..  lol love loop holes








6' flex plus 14' ridgid,  is how i read the max to be


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## nealtw (Feb 2, 2016)

You can put it on the roof.


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## slownsteady (Feb 2, 2016)

Make sure they take the shortest route available. Don't let them use flexible ducts. You could be proactive in selecting a nice looking hood (or whatever) if the front will be visible.


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## nealtw (Feb 2, 2016)

If you have a choice, between what looks good and what works best, go with the what works best, The health of the house is the most important part.


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## merk (Feb 3, 2016)

yeah I'm going to tell them to vent it out the front - it shouldn't really make too much difference as far as appearance of the house goes


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## slownsteady (Feb 3, 2016)

buy a nice azalea for your garden. plant it right in front of the vent


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## merk (Feb 3, 2016)

slownsteady said:


> buy a nice azalea for your garden. plant it right in front of the vent


That wont really work since right in front is concrete... i think. I'll worry about it once they are finished, which they were supposed to be today but didnt even start yet


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