Hello. I am planning to relocate ducting on my gas dryer. Planning to cut a hole in the bottom plate of the wall behind the dryer and route the duct through an interior concrete slab crawl space. It will exit through a hole in the rim joist. I watched several online videos, still have some questions.

1) Is it worth trying to line up the wall inlet with the dryer exhaust port to eliminate bends in the connector duct?
2) The wall behind the dryer is a 2x6. Is it ok for the duct to be in contact with the bottom plate? (I guess the duct will be hot when the dryer runs)
3) Should the wall vent be slightly tilted back toward the wall to help the damper close completely?

Thank you in advance for your advice.

 

1. Depending on your dryer's exhaust location it can sometimes be better to have the two offset from each other. This can provide room for the loop/fold of flex pipe. This is especially helpful if you use a more semi rigid flex pipe and not the cheap, really flexible plastic (which you shouldn't use).

2. Yes, dryer exhaust can tough flammables. Here is a site with codes: https://www.howtolookatahouse.com/Bl...yer-vents.html

3. What damper? There should only be a damper on the vent hood on the exterior of the home. There is NO damper in the exhaust line.

 

I've dealt with a dryer that had the outlet and wall opening that were offset by a few inches. Being 6" away from the wall flex duct would not fit so I had to use one of those offset adjustable ducts to fit, it was a total PITA, had to tear one apart and rebuild to make it fit the small offset.

I vote to align them for a simple run of duct, flex or solid. As a note solid is much better, you will rarely have to clean them vs a flexible duct.

For the damper, your probably referring to the external damper/louver they close ok as installed vertically.

 

Pilot Dane, Marq1. Thank you for your quick responses. Yes. I was referring to the damper/louver in the exterior vent hood.

 

I am planning to drill a 4-1/4" hole in the wall bottom plate behind the dryer (see picture). That wall is 2x6 but sits on a 2x10 end-joist (the rim joist that runs parallel to the floor joists). I will be putting a 1/4" deep groove across the width of that end joist.Want to know if that groove will cause any issues?
Thank you

 

Why going down and not horizontal out the side wall?

 

Hi Marq1. That's a separation wall between our townhouse unit and the next one.

 

Why cutting into wall and not just dropping straight down through floor? Is dryer pushed tight to back wall? Can you afford to have 4 inches space there? Where is gas line?

Some dryers have side outlet capability. Not enough space for 4 inches behind maybe exit side and turn down through floor.

Demising walls between units have fire ratings and cutting in may compromise that.

 

Hi 2john02458
The gas line is to the left of the planned location for the vent. It goes into the wall and down into the crawls space through the bottom plate. A washing machine and a utility tub are on the left of the dryer as well. Garage entry door is to the right of the dryer and pulling the dryer 4" away from the wall will interfere with the opening of the garage door.

Thank you for the heads up on the fire rating. I am aware of the requirement. The drain for the utility tub and the water pipes for the washing machine are going through that wall and down into the crawl space through the bottom plate. There is an existing dryer vent in that wall going up to through the top plate and makes a few 90 degree bends and goes up through the attic to the roof. Most of it is not accessible for regular inspection. I managed to take a peek at a portion of that pipe and the joints. Most were leaking into the ceiling cavity and into the attic. A lot of lint has accumulated over the years. So I am planning to relocate the duct down into the crawl space and out through a wall. Crawl space has concrete floor and open to the utility room. Temperature remains close to the rest of the basement. The relocation will allow for regular inspection and maintenance and easy cleaning through the wall vent.

If I put a hole in the floor instead, the transition flex duct needs 6" clearance from wall for the 90 degree bend to connect to the dryer exhaust, per my measurements. The floor is tiled too. Not my preferred material to put holes in. So the plan is to line up the wall inlet with the dryer exhaust which seems to offer the smallest clearance between the wall and the dryer.

Sorry for the long reply but I wanted to share my thinking because you asked a good question.