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Re: wave ventilation

Saw your post about removing moisture and smell from the basement. I too have this problem and am using a dehumidifier. There are four levels to my house and two of the lower floors remain damp. I saw the "wave" ads but can not afford the cost. If you could, please send me more detailed instructions on your installation. Thank you.

Re: wave ventilation

There are pictures and instructions in previous posts. There's a link to the fan you'll need as well. I will be constructing one next year as summer will be over shortly. I also have another question for njlou; Do you think this home made system would work in a crawlspace under a cabin? The crawl space is about 4 feet deep.

Re: wave ventilation

For crawl space ventilation, I have seen a very nice fan that fits in the standard vent openings. I saw it in Lowes, but I am sure they all have them. It was in the section with attic fans.
It was a small unit and probably would be a cinch to install. I was considering that but in my application, it wasnt powerful enough.:)

Re: wave ventilation

I had trouble finding the exterior "T" on the recommeded website. Found the fan and couplings. Thank you in advance for your help. BTW - great solution for smelly basement.

Re: wave ventilation

To njlou -

I ordered the fan and couplings from RE Williams site. They did not know what I was talking about with their exterior "T". Is there another name for this piece? Can I purchase it at local Home Depot? Thank you in advance for your help!!

Re: wave ventilation

Look under radon accessories:

"PVC Exhaust Cap Schedule 20 4"" Cap"
PVC Exhaust Cap Schedule 20 4" Cap
Sale Price: $14.95

Wave Ventilation vs. dehumidification... or both?

We have a constantly moist basement - not standing water (the perimeter was trenched with a French drain system to a sump pump), but constant moisture from below leading to mushrooms growing on the floor (the floor can look dry, but if you set something down on it and pick it up 24 hours later there's a dark, moist patch where the thing was resting). We currently have a standard room dehumidifier running all the time to keep it in check, but it's expensive and probably not rated for that, so we need a new solution. I'm going to throw a couple of buckets of DampRid down there and see how that goes.

A more serious basement dehumidifier seems like a good option, but we also want to consider the wave ventilation/njlou home-brew solution (the market wave ventilations systems do seem terribly expensive). However, we have gas heat and the furnace and boiler in the main basement room, so I don't know if the negative pressure issue will be a problem. If we install a ventilation system in the opposite corner, say 20 feet away from the furnace and boiler, will that help at all? It's a 100-year-old house, so there's plenty of air flow, but would we need to install a vent for added flow?

The basement is about 900 sq ft. - given all of this, can anyone suggest the best option? Should we try the njlou $200 ventilation system first and see if that works, or go with $1000 serious dehumidifier because the negative pressure issue might be a problem? Or should we try both? Would that be overkill in a space that size?

Any advice or help would be most appreciated - thanks to everyone who has been involved in this thread so far!

Re: wave ventilation

I have to tell you this works GREAT !!!!
For years I have gone with a humidifier (and went thu a few of them and thought I would give this a try..
After a few hours my wife asked what I did to get the smell cleared up in our basement, I guess I have about 1500 sq ft with
multiple partitions.
Within 48hrs the humidity in our basement went from 75% down to 45%, and there was no dampness or smell (don't know how low it will go).
I guess my only concern is in the winter when I will tend to suck out heated air from the rest of the house, but then I can just unplug it since the humidity is low.

One comment I'll make was the fan (Radionair RP151) calls for 4" PVC but I wanted a smaller appearance and tried 3", but it makes more noise so went with 4". Still a little too noisy for me in the basement, I saw a muffler on the net they sell I may try use(they also sell a 4"PVC externaly vent).

THANKS for your work, and for posting it worked exactly the way you drew it and still only cost about $200.

Re: wave ventilation

I understand the possible issues related to the wave ventilation system (its cost, negative pressure...etc). But has anyone here actually used it? If so, what's your opinion? Thanks...will wait to hear.

steve c
Re: wave ventilation

I have a 1926 home here in Ca.very close to the beach and have the same problems descibed here in this post. We have used 2 dehumidifiers on and off as needed.
I have few questions about this fan setup. My basement is very small, the house is a single story about 2100 sq ft, the basement houses the 2 down draft furnaces and a water heater, and is roughly 12'x12'. I have several vents around the perimeter of the raised foundation.

Could I benefit from this system even though my basement is small?

Does this vent run 24/7?


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