Venting Our Frustrations

Today's project was pretty straightforward:  Install a dryer duct through the crawlspace and out the west wall of the house.  Easy enough.

The current dryer vent is illegally routed straight through the wall and into the garage.  From the day I bought the house, we've always wondered where all of the lint went in the garage.  But after reading code, venting into the garage is definitely not allowed.  And I want to do a job right!

But before we got started on that project, Dad took a slight detour and started working on my kitchen faucet sprayer which does not spray with any sort of power.  He took apart the sprayer, and a nice steady stream of water makes it to the sprayer head.  So it had to be something in the head.  So we opened it up, and eeeewwwwww!!!  Gross, gross, gross.  The Moen sprayer head was actually flaking its chrome finish, and parts were getting lodged inside the sprayer head, but even more than that, there was some nasty sludge underneath the sprayer handle which also blocked the water.

Look at that gunk in there!

I don't even know what this sludge was...just gross stuff.

Pretty gross stuff.  So we cleaned that, and the sprayer now works about 90% power.  Cold water is powerful, hot water not so much.  So that is another issue altogether.  Always something!

Well, Pa and I went back to working on the dryer vent issue.  And we ran into some major headwinds.  Dad had told me to check the west wall to make sure that a floor joist wasn't installed close to the outer joist.  I mean, it's a possibility, but what are the chances?

Well, if you're working on a project with me, chances are pretty good!  Sure enough, the last floor joist WAS installed about two inches away from the outer wall one.  sigh.  The entire west wall was now off limits, as I couldn't get a 4-inch dryer duct through the 2-inch crevice.  And I didn't want to put a 4-inch hole into a 10-inch floor joist.

Now what?

So I looked at other options around that area.  And I looked up housing code in terms of dryer venting.  Basically, the code is simple...

M1502.5 Duct construction.
Exhaust ducts shall be constructed of minimum 0.016-inch-thick (0.4 mm) rigid metal ducts, having smooth interior surfaces, with joints running in the direction of air flow. Exhaust ducts shall not be connected with sheet-metal screws or fastening means which extend into the duct.

M1502.6 Duct length.

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. The maximum length of the exhaust duct does not include the transition duct.

M1502.2 Duct termination.
Exhaust ducts shall terminate on the outside of the building or shall be in accordance with the dryer manufacturer’s installation instructions. Exhaust ducts shall terminate not less than 3 feet (914 mm) in any direction from openings into buildings. Exhaust duct terminations shall be equipped with a backdraft damper. Screens shall not be installed at the duct termination.

M1502.4 Transition ducts.
Transition ducts shall not be concealed within construction. Flexible transition ducts used to connect the dryer to the exhaust duct system shall be limited to single lengths not to exceed 8 feet (2438 mm), and shall be listed and labeled in accordance with UL 2158A.

In other words, I had 25 feet to get from my dryer to out of the house, and I lose 5 feet for every 90-degree turn and 2.5 feet for every 45-degree turn.  Easy enough.  And I have to exit the house at least 36 inches away from a window or door.  Well, not so easy...

So I started looking at my options in this house.  I even called the local building code guy to see if Springfield had any different local codes.  Sure enough, I was granted 35 feet instead of just 25 feet, but the rest remained the same.

So looking at my house, I had some hurdles.  If I went to the west wall, I had the floor joist issue.  If I went due south over the large ductwork and in between a floor joist, I came out underneath my bay window.  Not allowed.  Dad asked about just running along the interior of the garage and out that way.  I found that way too unprofessional and tacky.  Functional, yes.  But no thanks.  So I was left with literally just TWO more options.  And those were to run the duct at 45-degree angles towards the exterior of the south of the house.

The small area where I needed to put the 4-inch dryer duct hole!  I was working around quite a bit of obstacles!

What I really wanted to do.  Run the duct from dryer out the wall.  But it brought it up underneath a window...not allowed.

It was such a straight and easy shot!  Just not to code.

So I went back down into the crawlspace to see my options.  If I went southeast, I ran into my contractor's extra support for the floor joists close to the kitchen wall upstairs which made running a duct through there difficult.  That left just one last option.  I could run it southwest and out the south wall, but I had a very tight situation.  The gap between the two windows I was running in between was 70 inches.  The code requires 36 inches to each one.  Hmm.

Literally trying to figure out my options.  We are looking to the south.  I have a 45-degree to the southwest, to the southeast, straight out, and then out west.  Only two were viable, but only one was really doable!

So what if instead of measuring side-to-side, we measured diagonal to where the hole was going to be?  I mean, it was my only option, so I went with it.  It was a freezing cold single-digit day, but we did the work.  I bought the ducts and an expensive $20 4-inch hole saw and $10 mandrel from Harbor Freight.  But it was necessary as it took all the work out of it.

So I cut myself a hole in my house from the outside, and then after careful measuring I cut myself a hole in the floorboard behind the dryer.  The vent is now ready to be installed.

I finally settled on this location in the back of my house!

The exterior vent is in.  It was so cold outside!

The hole is made.  Time to do the duct tomorrow.

What a day!  We literally spent most of it contemplating our issue of trying to obey code.  It became very apparent why the original contractor didn't vent it out!  It was too difficult!  But it's crazy to think that some homeowner has been venting into the garage for 25 years...illegally.

So I still have to run the duct.  But at least I know where I'm running it from and where I'm running it to now.  Today was just a day of contemplating and researching!  But that's part of doing something right.