Dryer vent ideas

[Spork]

My dryer vent was plumbed such that it vents up through the wall, then through the attic and out a vent on the roof.  I've never had one of those before and always thought shorter and simpler was better.  It looks like I was right.  We get a pretty reasonable clog in this thing a couple of times a year.   I'm trying to think of a better way to do this.

Here is the original framing.  This was a panoramic shot with a bunch of snaps stitched together, so ignore where some vertical areas don't meet up.  (I took panoramics of every room so I could remember what was in the walls where.)




...and here is the basic layout of the area in question:


My current ideas are:
1) mount a cabinet door on the wall in the garage on the other side of the wall.  Cut a hole in the drywall and sheet metal of the dryer vent and use that as a clean out.  Repair the hole with a little oversized sheet metal and sheet metal screws.
advantages: Probably the neatest solution.  Easy to clean out.
disadvantages: still venting up and out, so likely to still really get plugged up.  Repair of the vent will leave sheet metal screws sticking into the chamber, which will just grab more lint.

2) run a vent through the wall (at the red dot), along the inside of the garage and exit at either the yellow dot or the blue dot.
advantages: gets rid of the long upward vent.  Relatively easy to clean out.
disadvantages: ugly... but it's in the garage.  It is still a pretty long vent.

3) run a vent on the laundry room side of the wall directly out to the green dot
advantages: slightly shorter run.  Not visible
disadvantages: harder to clean out.  This also would run through cabinetry and be a hindrance to putting stuff in the cabinets.

[Mrs. PoP]

Do you have any bends in your vent, or does it just go straight up through the wall, the attic, and through the roof?

From what I remember about reading the dryer vent code (from FL building code - yours may differ) last year...
- maxmimum length of 25 feet (I think), which you need to label the run length with a placard when it's done
- any bends require you to add a proportionally larger length depending on how tight the bend is.  We ended up temporarily installing some large diameter 90-degree turns (the typical ones are 4 or 6" diameter bends), because those don't add penalty length to your run length , whereas the 4 or 6" ones required you to add as much as 5 feet to your effective run length per bend.  (The manufacturer was called Dryer-Ell and they seemed to very specific solutions for a very niche - dryer vent - market.) 
- lastly, and this was what our inspector considered most important, there should not be ANY screws piercing the interior of the vent.  Our inspector told us screws penetrating the interior of the vent should be considered fire hazards. 

How do those guidelines fit in with what you have?

[Spork]

Ours is (rough guess) about 15 feet long.

It obviously bends 90 degrees where the inlet turns upwards up the 2x4 cavity.  At the top, it goes to metal flex duct.  (I am not a fan of that stuff).  This is 4 inch flex duct that snakes to the roof vent.  No huge bends if I remember correctly.  But snakey bends.

Currently there are no (known) penetrations of the vent... and I was hesitant to add any for just the reasons you outline.  The problem is, without a clean out mechanism or a re-design... I think this is more of a fire hazard the way it is.  Lint is blown up the stack, then settles at the bottom.  Eventually there is a massive compressed wet blob of lint that pretty much plugs the stack entirely.

[Fishindude]

Assume it is electric?
Why not just dump it through the wall into the garage?   Could make a trap of sorts to catch the lint.

[zolotiyeruki]

I assume that wall is load-bearing? 

If it were me, I would have laid out the room differently in the first place, put the dryer all the way against the exterior wall, and put in a 2-foot run to the exterior :)  Can you post a pic of the room as it's currently laid out?  If there's a cabinet to the right of the dryer, could you swap their positions, putting the cabinet between the washer and dryer?

[Spork]

Assume it is electric?
Why not just dump it through the wall into the garage?   Could make a trap of sorts to catch the lint.

Yes, electric.

I considered that, too.  I was worried about dumping that humidity in the garage.

[CowboyAndIndian]

Can you  move the dryer to the right of the washer?

If so, you can vent thru the red dot and with a very short run.

Edit: I see the dryer is to the right of the washing machine. Can you move the dryer closer to the exterior wall and vent thru the wall at the red dot.

[Spork]

I assume that wall is load-bearing? 

If it were me, I would have laid out the room differently in the first place, put the dryer all the way against the exterior wall, and put in a 2-foot run to the exterior :)  Can you post a pic of the room as it's currently laid out?  If there's a cabinet to the right of the dryer, could you swap their positions, putting the cabinet between the washer and dryer?

Yes, load bearing wall.  And yeah, in hindsight I think I would have laid out the room differently as well. 

There is a cabinet to the right.  Moving it, while possible, would just look too funky (IMO).  There are also upper cabinets that are deeper above the washer/dryer.  It would look really strange if it all got juggled around.

[Fishindude]

The humidity from a load or two of clothes drying isn't going to negatively affect things in the garage too bad.
Assume it's unheated and you have wet cars, etc. parked in there sometimes anyway?

[zolotiyeruki]

I assume that wall is load-bearing? 

If it were me, I would have laid out the room differently in the first place, put the dryer all the way against the exterior wall, and put in a 2-foot run to the exterior :)  Can you post a pic of the room as it's currently laid out?  If there's a cabinet to the right of the dryer, could you swap their positions, putting the cabinet between the washer and dryer?

Yes, load bearing wall.  And yeah, in hindsight I think I would have laid out the room differently as well. 

There is a cabinet to the right.  Moving it, while possible, would just look too funky (IMO).  There are also upper cabinets that are deeper above the washer/dryer.  It would look really strange if it all got juggled around.

Gotcha.  In that case, I'd extend the straight, rectangular duct straight up through the roof.  No bends, no corrugated anything to cause pressure loss.  I wouldn't be too concerned about lint falling to the bottom and building up--the amount of airborne lint in the duct at the moment when your dryer shuts off is really, really tiny.

[paddedhat]

I would try a few things before you go any further. First, define flex duct. There is stuff that is total crap, basically a foil version of the cheapest plastic dryer hose, with thin metal fabric and a metal, Slinky like inner core. If this is your stuff, replace it with semi-rigid metal, which is much smoother and more substantial. Next, insulate the run in the attic. Buy a 25' piece of 4 or 5" flexible insulated HVAC duct. It comes in boxes in the ductwork isle of the big box stores. Cut a piece about a foot longer than the flex in the attic. Strip the inner core out of the flex duct. Now you have a fiberglass wrap and foil outer layer. Undo the attic flex, slide your insulation assembly on to the flex, and reconnect the flex. Secure your new outer wrap with a pair of huge Tie-wraps, which are also found with the flex duct at Home Depot. This may make a huge difference, as the vent may be condensing on the interior and causing lint to stick to the sides of the flex pipe.  Now take a good look at the exhaust port on the roof hood. Does it have a built in hardware cloth screen to keep squirrels and other undesirables out of the pipe? Is it all clogged with lint? Does it make sense to rip it out and let the air flow better? Finally, what does it look like behind the dryer? Is there a nice tight, smoothly installed piece of semi-rigid pipe running from the dryer to metal flange in the wall? Can you make the run shorter and smoother with any off the shelf fittings from the big box store, or by rerouting the flex?

All of these ideas will cost very little and MIGHT solve your problem. If not, I would install a dryer vent booster fan in the attic, right at the transition from the wall ducting to the flex. That will solve the problem, and be a lot cleaner and easier that your other potential solutions.

[Spork]

My flex duct is the semi-rigid metal stuff -- though I really hate that stuff.  It tends to dent and kink so easily.  It also isn't very water tight when there is condensation.  It leaks out the seams.  But it isn't the slinky wrapped stuff.

Great idea on insulating it.  As I mentioned: I do get some condensate.  I "fixed" it by putting a drip pan under a low spot in the run.  My attic is insulated at the roofline, so while it isn't super cold in the winter... let's face it.  I am a mustacian and my house is in the 60s in the winter.  Send some hot, wet dryer air up there and it's going to condense.

BUT... I think you really hit the nail on the head with the exhaust port.  There was a nice 1/4 inch mat of lint there.  I removed the hardware cloth and the compressed lint washrag. 

I'm still skeptical of sending all that stuff up and out...  But I'm willing to give it a few months and see if it gets plugged again.  And tossing a little insulation around the duct can't hurt my condensation issue.

[argonaut_astronaut]

Two things:

Replace that flex line with rigid.

Open up the drywall and put in one of these (http://smile.amazon.com/Fantech-Lint-Trap-Dryer-Booster/dp/B00EJPHJVK?sa-no-redirect=1)

[Spork]

Two things:

Replace that flex line with rigid.

Open up the drywall and put in one of these (http://smile.amazon.com/Fantech-Lint-Trap-Dryer-Booster/dp/B00EJPHJVK?sa-no-redirect=1)

While some sort of clean out in the wall seems like it would be optimal...

"This product is not designed to be installed inside of walls."

If I could find one that would neatly fit in my vertical, rectangle vent line, I might try it.  That's what my original thought was -- to just cut a hole into the vertical for cleanout.  My main concern there is making something that is smooth and won't just be another lint trap itself.

[argonaut_astronaut]

Two things:

Replace that flex line with rigid.

Open up the drywall and put in one of these (http://smile.amazon.com/Fantech-Lint-Trap-Dryer-Booster/dp/B00EJPHJVK?sa-no-redirect=1)

While some sort of clean out in the wall seems like it would be optimal...

"This product is not designed to be installed inside of walls."

If I could find one that would neatly fit in my vertical, rectangle vent line, I might try it.  That's what my original thought was -- to just cut a hole into the vertical for cleanout.  My main concern there is making something that is smooth and won't just be another lint trap itself.

I would go talk to an HVAC/ducting company in your area to see if they have something that would work. Seems like a screen filter should be doable.

[Le Poisson]

How Handy are you? Is the garage down one step or two?

I would relocate the dryer to the current location of door 5. A 2 foot run of duct across the back of the garage has you venting to the backyard. Frame in door 5 to the right of the existing dryer location. If you only need one step down into the garage, you should be able to do this and not lose parking. 2 steps might cost you a parking spot.

What you do with the wall and door 7 is up to you. (I might remove it depending on floor finish, then put a door in at the mud bench.)

You really don't want a direct vent into the garage. Trust me, I had to repair that in my current house. The moisture and cold air were a bad combination.

[paddedhat]

My flex duct is the semi-rigid metal stuff -- though I really hate that stuff.  It tends to dent and kink so easily.  It also isn't very water tight when there is condensation.  It leaks out the seams.  But it isn't the slinky wrapped stuff.

Great idea on insulating it.  As I mentioned: I do get some condensate.  I "fixed" it by putting a drip pan under a low spot in the run.  My attic is insulated at the roofline, so while it isn't super cold in the winter... let's face it.  I am a mustacian and my house is in the 60s in the winter.  Send some hot, wet dryer air up there and it's going to condense.

BUT... I think you really hit the nail on the head with the exhaust port.  There was a nice 1/4 inch mat of lint there.  I removed the hardware cloth and the compressed lint washrag. 

I'm still skeptical of sending all that stuff up and out...  But I'm willing to give it a few months and see if it gets plugged again.  And tossing a little insulation around the duct can't hurt my condensation issue.

If you still have issues after you insulate, I would strongly suggest that you look at a booster fan. They are inexpensive and start when the internal pressure switch senses that the dryer is pushing exhaust. My HVAC contractor is the guy who turned me on to them. He told me of a customer who had an impossible situation of a vent running 40' horizontally, existing the basement, and running another ten feet under porch floor joists, to a vent hood on the rim joist of the porch. Obviously, it was a failure, but there were no options that didn't involve insane amounts of renovations. He threw a fan in, as a Hail Mary move, with little to lose but the cost of the fan. The thing works great, and it saved the customer thousands.

[Spork]

My flex duct is the semi-rigid metal stuff -- though I really hate that stuff.  It tends to dent and kink so easily.  It also isn't very water tight when there is condensation.  It leaks out the seams.  But it isn't the slinky wrapped stuff.

Great idea on insulating it.  As I mentioned: I do get some condensate.  I "fixed" it by putting a drip pan under a low spot in the run.  My attic is insulated at the roofline, so while it isn't super cold in the winter... let's face it.  I am a mustacian and my house is in the 60s in the winter.  Send some hot, wet dryer air up there and it's going to condense.

BUT... I think you really hit the nail on the head with the exhaust port.  There was a nice 1/4 inch mat of lint there.  I removed the hardware cloth and the compressed lint washrag. 

I'm still skeptical of sending all that stuff up and out...  But I'm willing to give it a few months and see if it gets plugged again.  And tossing a little insulation around the duct can't hurt my condensation issue.

If you still have issues after you insulate, I would strongly suggest that you look at a booster fan. They are inexpensive and start when the internal pressure switch senses that the dryer is pushing exhaust. My HVAC contractor is the guy who turned me on to them. He told me of a customer who had an impossible situation of a vent running 40' horizontally, existing the basement, and running another ten feet under porch floor joists, to a vent hood on the rim joist of the porch. Obviously, it was a failure, but there were no options that didn't involve insane amounts of renovations. He threw a fan in, as a Hail Mary move, with little to lose but the cost of the fan. The thing works great, and it saved the customer thousands.

If I go that route, I'll also probably replace the flex duct with some rigid ductwork.

[BudgetSlasher]

You really don't want a direct vent into the garage. Trust me, I had to repair that in my current house. The moisture and cold air were a bad combination.

Plus the lint; I know some people have suggested making a trap or filter, but to catch all the lint before blowing it into the garage it would have to be very fine and probably very frequently, even then I am no sure how much back additional pressure it would exert on the system.

I know for me a fine layer of lint dust accumulating throughout the garage would be very annoying since my workshop is in the garage.

[Le Poisson]

You really don't want a direct vent into the garage. Trust me, I had to repair that in my current house. The moisture and cold air were a bad combination.

Plus the lint; I know some people have suggested making a trap or filter, but to catch all the lint before blowing it into the garage it would have to be very fine and probably very frequently, even then I am no sure how much back additional pressure it would exert on the system.

I know for me a fine layer of lint dust accumulating throughout the garage would be very annoying since my workshop is in the garage.

Your tools will rust, your drywall will absorb the moisture, mold sets in. Cooked goose. Relocating the dryer vent from the garage to an exterior wall is the most searched article on my blog. Its not a very exciting one, but I guess a lot of folks are faced with this.