Waterproofing concrete questions

[LeakySeals]

Using the concrete slab under the deck during the summer as another outside area. Not covered so it gets wet. it doesn't get a lot of sun so takes a while to dry out. Gets some mildew and algae if there is a lot of rain.

I bought some Olympic multi-surface waterproofer from Home Depot with hopes that it will help keep it dry. I put it on with a roller. White milky substance that was absorbed into the concrete. It dried like nothing was there. Then 24 hours later it rained. I was expecting "waterproof". Instead I still got a wet slab but it appeared to repel water a little better.

Is my expectations of the word waterproof too high? Or is this another VOC product underperforming?

 

[Spector]

They under perform expectations IMO and last maybe a year or less. Not sure they are worth the effort.

 

[demarpaint]

Originally Posted by Spector
They under perform expectations IMO and last maybe a year or less. Not sure they are worth the effort.


+1 I often advise customers against it.

 

[ragtoplvr]

On a related note, there is a concrete product used for cemetery vault covers called I think Torganol. I number of the relatives have them, and they are not doing well. I had to remortar the name and date plate on several of them. They have mildew and some minor freeze damage. Is there a coating I can put on these to extend their life.

Just another reason to be cremated and scattered. Nothing last forever.

Rod

 

[tmorris1]

How do you expect it not to be wet when it rains? The waterproofing will probably help bead up the water, but it still has to evaporate. It can't get rid of water. Put a fan on it.

 

[maxdustington]

That's a fact of life with a slab under a deck. All you can really do is make sure you deck boards are a nail head apart and pressure wash it when it gets gross. You could try to put something underneath to deflect the water, but that could rot your deck boards.

Painting masonry is stupid IMO. I hate painted brick with a passion.

 

[P10crew]

I always wanted to roll on a gallon of yellow anti freeze. Where I'm at they use urea on the roads and it just kills your concrete where the vehicles sit. I'm thinking anti freeze on a hot day would have prevented this sort of damage and might help seal it up.

 

[Warstud]

Google: Under deck drainage system

 

[Linctex]

Originally Posted by P10crew
Where I'm at they use urea on the roads.


???? For what purpose???

Last I heard, Urea is used as a fertilizer ingredient, and also in DEF fluid.

 

[LeakySeals]

Originally Posted by tmorris1
How do you expect it not to be wet when it rains? The waterproofing will probably help bead up the water, but it still has to evaporate. It can't get rid of water. Put a fan on it.


My expectation was no penetration. Just run off. I didn't expect it to stop the rain but that would be nice LOL

 

[LeakySeals]

Maybe my interpretation of waterproof is wrong. To me it means no penetration. No absorption. This product is repelling water but not waterproof. So the product description is misleading IMO.

This morning. Beading up but still penetrating the concrete so it's still going to get damp. Hopefully it will dry quicker though. That would be a help

The untreated areas were the last to dry.

 

[PimTac]

Those posts are going to be a problem in the future. I would worry more about that than the concrete.

 

[RhondaHonda]

Originally Posted by PimTac
Those posts are going to be a problem in the future. I would worry more about that than the concrete.


Exactly. Those posts should be mounted on concrete piers with galvanized brackets so they don't get soaked constantly.

 

[LeakySeals]

Originally Posted by RhondaHonda
Originally Posted by PimTac
Those posts are going to be a problem in the future. I would worry more about that than the concrete.


Exactly. Those posts should be mounted on concrete piers with galvanized brackets so they don't get soaked constantly.


I don't know why the builder did what he did 20 years ago. I'm guessing lousy project management. And the deck was up before the slab was in. Something stupid like that wouldn't surprise me. I plan on staining the whole deck including the post with TWP in the next week or so.

 

[PimTac]

Originally Posted by LeakySeals
Originally Posted by RhondaHonda
Originally Posted by PimTac
Those posts are going to be a problem in the future. I would worry more about that than the concrete.


Exactly. Those posts should be mounted on concrete piers with galvanized brackets so they don't get soaked constantly.


I don't know why the builder did what he did 20 years ago. I'm guessing lousy project management. And the deck was up before the slab was in. Something stupid like that wouldn't surprise me. I plan on staining the whole deck including the post with TWP in the next week or so.




It looks like a hack job for sure. Those posts may already be rotted below the concrete surface. How old is the concrete slab?

The suggestion to put those posts on pier blocks with galvanized saddles is a good one.

 

[doitmyself]

It's been well over a decade since I did any serious concrete sealing and I have forgotten more than I ever learned. There are commercial products available that probably would work much better than what is available at the big box stores. The problem is that you need to live near a sizeable town with distributors. You need to have a good concrete jobber in that town. And, you need to spend a fair amount of time becoming educated about all of the products.

The last sealing job I did, I used products from this company that had a local supplier: https://www.euclidchemical.com/

Most people should probably just hire it out. Sorry for the lack of any useful information here.