I should note that I have 6" walls in the back and side of the dryer, and the wall would be on the right side of the dryer.

Almost all dryers are designed to vent out the back. Some, but not all, can be vented downward or out through the side, but most manufacturers recommend venting from the back, regardless of possible alternatives. Usually side venting dryers are designed to vent from only one side or the other, but not both. You'll need to choose a particular dryer brand and model to determine the possibilities.

If you plan to locate the back of the dryer against an outside wall, you'd be wise to exhaust out the back through the wall. That configuration will require the shortest vent run with the fewest elbows or turns in the duct, which is always desirable. It will also allow you the maximum range of choices when it comes to selecting a dryer.

I can't think of any reason that your house being air-conditioned would have any bearing on the direction of the dryer venting. You're still going to be drawing conditioned air into the dryer and exhausting it to the out of doors, regardless of the dryer vent location.

The laundry room is not near an outer wall, so simply having it vent directly behind is not an option. My kitchen range is on an outer wall, so I will vent directly out that way.

wa8b, you are saying that the natural venting axis is behind, so that's OK. What about the alignment issue? Do I need to pick out the dryer first, then determine where to put the vent?

Jakvis, I'm glad you replied. I was thinking that it could be a real problem for condensation and lint getting trapped -- either a moisture/mildew/no airflow problem or a trapped lint/no airflow/fir hazard. Both are things you want to avoid. Mine has always gone straight out the back, so I've never seen it happen, but sure makes sense.

Yeah it can be a real mess when you vent through the slab.

The other thing I see and most contractors don't do right is when you install a dryer vent or a down draft cooking vent through a crawl space, the seam of the vent pipe needs to be at the bottom (6 o'clock position)of the pipe. This allows the condensate/water to seep through the seam and not collect in the pipe.
Just one of the tricks of the trade.

Jackvis is correct. You are asking for trouble venting it in the slab. Besides national building codes state the length of a dryer vent should only be 25'. With every 90 degree turn it reduces the allowable length by 5 feet. Therefore in order to operate correctly and be up to code you can only have a vent of 5 feet or less. As a professional dryer vent cleaner we see many of these useless vents. it is better to go straight up the wall and through the attic and vent on the roof rather than go through a slab. Surprisingly, the vertical vents work well. Ease of cleaning them is exponentially greater than a slab vent. Incidentally we find many things homeowners have got stuck in them trying to clean them as well as we have had many, many problems. Run from a slab vent like it has the plague. Recently we had to reroute one through the roof after a baby rabbit got in the vent and crawled all the way to the dryer and up inside it before dying. Once anything gets inside there is not any way to turn around. Save headaches and DO NOT DO IT.

Too late ...this post is 6 years old

It molds out houses from the inside out. It stained our wood floor, caused mold to grow on our wood floor in a line right above the dryer vent under slab.

Hi guys. I see this is a really old post but I’m having a similar problem In a newly built home. There is so much condensation in my dryer and the dryer hose is soaking wet. The dryer is vented through the wall to outside (concrete slab home)

When was the last time that you cleaned the exhaust hose?

I would not use the dryer until you have removed the hose, inspected for blockage & cleaned the entire length of the vent if needed.

As a professiona dryer vent cleaner. i found using a huge leaf blower with a speed of of aver 250 cfm or miles per hour, from the inside blowing it out the vent works magic. Stop up the vent around the blower with an old towel and let it go for about two minutes. urn it off go outside and look at all the muck you blew out. Wait a bit and do it again to help dry it out. A dryer puts out a gallon and a quarter of water off the clothes per cycle. Do this regularly and you should be ok

We just moved in 2 months ago and have only just bought a dryer a month ago, so this happened from just a month of using the dryer. I’m having the builder come look at it today. He swears it is vented up through the attic and to the roof outside so I might be wrong about it being through the slab.. I guess we’ll see today. The laundry room is on the second floor. When I pulled the hose out of the back of the dryer it was SOAKING wet inside!! Not good.

My laundry room in just inside the door to the garage. The dryer vent runs in the slab through the garage floor to the outside. My husband has to pull the dryer out and disconnect the hose and blow it out with the leaf blower. He also uses a shop vac to suck out water from the outside exit end of the pipe. The laundry room is on the first floor of a slab house and there is a second story above the laundry room. I would love to hear from an expert how we should fix this poor design. Thank you!

Clothes dryers should always, always, always be positioned at an exterior wall for a straight-through, shortest-path exhaust route to 1) eliminate airflow restrictions, 2) minimize drying energy and time, and 3) minimize maintenance procedures.

While this is the ideal rarely is it the case anymore. Builders opt for making the laundry room more convenient to the kitchen which more often than not is in the central part of the home. As a chimney sweep for 40 years who tackled dryer vents early I learned convincing builders to alter their habits is futile much to the peril of homeowners. We suggest rerouting the vent up and out the roof. This is not optimum but normally the only feasible way to do it. The pipe should be metal but not aluminum and each joint should be taped with METAL tape not duct tape which will fail after a few years of heated use.

Dryer vents can only be 35 feet long according to building codes and each 90 degree bend subtracts 5 feet from that total. Slab vents have 4- 90's thereby making the legal limit of the vent to be only 15 feet long. Rarely are they that short.

The cleaning procedure detailed above is normal and time consuming but necessary for this faulty dryer vent design. As dryer vent cleaners we have perfected a system that works most of the time yet there are those that must be rerouted to be made more efficient.