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Dehumidifying the Basement Shop & Dryloc the Walls in an Old House?

1328 Views 15 Replies 11 Participants Last post by  JCamp
My shop is in the basement of my 100 year old house just outside Philadelphia. The basement gets humid in April and stays that way till October - so we use a dehumidifier. This keeps my tools rust free (mostly).

However, we haven't found a reliable dehumidifying unit - one that will last 2 years…we've gone through cheap pones - and not-so-cheap ones. Same thing : 1 or 2 years and they're done.

The basement walls are a parge/masonry-type material that could use some patching/maintenance. If I take on the patching, would it be a good/bad idea to try to seal the basement walls with a waterproofing product like Dryloc?

Also - anybody know of a reliable dehumidifier? I definitely need a new one of these (again - arrrgh)

Thanks !
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I have a block basement in the Midwest. The waterproofing paint works for awhile, but eventually fails in spots. The only real way to waterproof is from the outside. Yes, dig it up. Coat the outside. But painting the inside helps, but is not permanent. Good luck. I ran ac ducts down into the basement and scrapped the dehumidifier. ( Which is just an air conditioner the exhausts it's waste heat back into the same space. A dehumidifier heats the air that you need to cool to dehumidify.)
I have a stacked stone foundation in NY. I was getting some water in one room. I dug up the outside and repointed the joints then water proofed it. I didn't use dry lock on the Inside i used roofing paint. I have a keystones dehumidifier in the room also that's been there over 5 years.
Had a basement shop and same thing. 2 years was about what I found too. Seems all that matter is make them last long enough to get out warranty.

We build daylight basements inside a hill and I found a window A/C worked best and lasted longest. But here in the deep humid south A/C is pretty much a requirement.
Repointing/recoating the outside of the foundation is the way. While that's happening, you might as well install a french drain to ensure you don't get any water in the basement.

None of the standalone dehumidifiers are worth anything long term. Your best bet is probably a mini split A/C unit, honestly. It's pricier, but it should last 20+ years, and you get the ability to heat/air condition the basement if you want to.
This is interesting, I have left a window unit running in my small stand alone shop but saw an ad for damp Rid this morning and it got me thinking. Along with any other methods does anyone use Damp Rid in their shop?
I have a similar situation; 110 year old house, stone/block foundation with a basement workshop.

When we first moved in, every time it rained, we had puddles along the basement walls and in the corners. Putting gutters on the house and draining the water away from the foundation completely solved the problem. I still need to use a humidifier, but my Honeywell dehumidifier set at 50% is still running after 3 years with no problems. The dehumidifier drains directly in to a floor drain instead of the built-in reservoir.

Ultimately, the only permanent solution is to get the water away from your house. Trying to use a wall sealant means you'll have wet/saturated basement walls with only a thin film protecting your basement…the water will eventually find a way in, and your basement walls will never dry out.
Brewer has it. +1

We have a 200+ year old house with a rock and mortar foundation. The first defense is to make sure, sure, sure water drains away from the house. If not, you're in a losing battle.

Second and third defenses are French drains and sealing the outside of the foundation.

Sealing the inside of the foundation lets water into the structure. It will wick up inside the brick/mortar/cinder block for several feet above ground level and spall that. You can't win.

Dehumidifiers are good for helping control mold and rust. But you have to find a solution to disposing their water and dealing with their heat. Here in the mid-Atlantic we need to dehumidify in the summer when their additional heat is really a problem for the humans. Air Conditioning is much better if you can swing it.
AC is definitely better. It disposes of the heat outside. If you need to dehumidify in the cool months, then the dehumidifier is best.
+1 Above

Had a 'daylight' or walk out basement that leaked like a sieve when it rained.
Sealing wall with Dryloc last ~2 years, and push water and damage higher up wall.

Water has to have somewhere to go. Fix that 1st.
Then add drains, and seal outside.
After you fix water behind walls, probably want to upgrade sump pump to an enclosed system.
Once all this is completed, you won't need de-humidifier.
But you will want a min-split AC, as the lack of moisture evaporation cycle will make basement feel warmer.

Upgrading from a caveman to 21st century is expensive…... :)
Thanks to everyone for your feedback and ideas. It's been a vexing problem, as many of you have experienced the same.

Like Brewer, I routed my rain gutter water out of the broken-down clay pipes next to the foundation and farther away from the house. That was a great move that proved to be very effective.

THese days, I don't have active water seepage into my basement, and so I don't have a french drain nor any sump pump system like that. But, the basement is mostly below grade such that I have very narrow windows in the basement such that would be difficult to find a window AC unit to fit. I suppose if we moved to a mini-split for the 1st floor - I might be able to AC the basement more effectively than dehumidifying. Hmmmm.

In the cool months, I don't need to dehumidify, as the gas fired boiler keeps the basement dry in the cool seasons.
Look into a multi zone mini with two or three indoor units ( evaporators ). One can go into the basement.
Best I can figure, the Santa Fe is the most reliable. I got two cheap "house" ones from a member that had failed pumps. So I just use gravity drain in my workshop.

Dryloc will just make it hold water inside the wall. You want to stop it outside. Usually with proper grading, plastic for the first two feet around the house, foundation planting far enough away, gutters and downspouts working, you can be in good shape. Unless of course, you are getting some ground water which the only solution is a French drain.

The mini split HVAC units DO NOT DEHUMIDIFY. To get their efficiency, the coils run only a degree or so off the dew point. I have to run a dehumidifier in the summer. So much for energy efficiency. If the mini-split were only SEER 14 or 15, the coils would be 5 degrees cooler and I would not have to run a NEGATIVE% efficient dehumidifier and total energy would be less. "The Government is on your side"
... The mini split HVAC units DO NOT DEHUMIDIFY. - tvrgeek
Sorry, have to disagree with this in-accurate generalization.
My Chinese (Midea) made, Mirage brand 18K BTU 19 seer Mini-split; does reduce humidity, has dehumidify target setting, and dehumidify only mode.
Funny, my LG mini in the shop requires a drain, and I collect the water for the garden. It also has a dehumidify setting. Any ac, mini or conventional, that is over sized for the space cools and shuts off before the moisture is removed.
If what you've already tried fails give a portable window AC a try. It will work on your small windows
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