Case against sealing a new concrete driveway?

[Raswan]

Getting a new one installed next week, and just sealed a 70-year old basement floor with a silicate sealer before putting down vinyl plank flooring. When I originally talked to the driveway guy he said sealing it at the beginning or once every x years was unnecessary, but as I read more about the silicate densifiers, it seems like something to at least consider. It would be around 600 square feet, so not that expensive.

What do you guys think? If so, would you do a topical treatment or a penetrating one?

 

[NutBucket]

So educate me on why you'd want to seal a driveway? Is it to prevent oil stains from setting in?

Just curious since my parents never sealed their driveway and it still looks new probably 2 decades later.

 

[Raswan]

Densifiers and hardeners like lithium silicate or sodium silicate penetrate the concrete 2-4 inches and react chemically, filling the pores. This makes the concrete way more waterproof and at the same time strengthens it by something crazy like 40%. So, increased durability and lifespan.

 

[NutBucket]

Ah, so stuff that doesn't much matter in SoCal LOL

 

[Raswan]

Haha. Probably not. Here in MN, maybe.

 

[NutBucket]

So does that mean the concrete guy is just trying to create future business for himself?

 

[Raswan]

Eh, hard to know. That's why I'm looking for some classic AT input from the pros. Could be overkill I guess to do it.

 

[highland145]

I have no idea but keeping water out should be a plus because of MN winters....right?

 

[olds]

Concrete takes a long time to cure. Will it cure with this stuff on it? If not, I'd wait a couple of months.

 

[Raswan]

Concrete takes a long time to cure. Will it cure with this stuff on it? If not, I'd wait a couple of months.

Right, you have to wait thirty days before application.

 

[Raswan]

I have no idea but keeping water out should be a plus because of MN winters....right?

One would think, yes.

 

[Ajay]

What are you trying to prevent/improve?
A different concrete formulation may get you what you want.

 

[Raswan]

What are you trying to prevent/improve?
A different concrete formulation may get you what you want.

The primary reason to go with concrete over asphalt is increased lifespan. If I can apply a densifier/hardener thirty days after install to further improve that for ~$150 by 40%, and there are no downsides, seems a no-brainer to me. Less pitting and chance of cracking down the road, etc etc.

My understanding of concrete driveway installation is there are no real "formulas." It's a matter of strength of the mix (3500psi in this case, which is common for car/SUV residential installations), and thickness (a three- or four-inch pour). Add in some rebar in there too, most of the time.

 

[Humpy]

Densifiers and hardeners like lithium silicate or sodium silicate penetrate the concrete 2-4 inches and react chemically, filling the pores. This makes the concrete way more waterproof and at the same time strengthens it by something crazy like 40%. So, increased durability and lifespan.

I believe the benefits are being greatly exaggerated.

Penetration is more like a 1/4", so only the surface gains strength/density/waterproofing. Which is great for polished industrial concrete floors, less so for a driveway.

A good crew, a good mix, and pouring when the weather will be cool and calm for a few days so the concrete can properly cure, is more important than anything for longevity. All of the concrete work that is still around from 50 years ago, and there is a lot of it, isn't still there because it had something sprayed on top of it after it was placed.

 

[echo4747]

Getting a new one installed next week, and just sealed a 70-year old basement floor with a silicate sealer before putting down vinyl plank flooring. When I originally talked to the driveway guy he said sealing it at the beginning or once every x years was unnecessary, but as I read more about the silicate densifiers, it seems like something to at least consider. It would be around 600 square feet, so not that expensive.

What do you guys think? If so, would you do a topical treatment or a penetrating one?

From personal expeience, I would ( and did) go with a penetrating sealer. About 9-10 years ago I had a new concrete driveway poured and I think sealed it about 60- 75 days after it was poured. This is the sealer I used: https://www.euclidchemical.com/prod...ts/penetrating-sealers/baracade-silane-100-c/. What I like about this sealer is it doesnt change the look of the cement after it dries and the concrete isnt slippery . What i did not like about the topical sealers were, they change the look of the driveway, and when it rains the water beads sits on top and freezes into sheets of ice and becomes a slip hazard. Topical sealers can only protect to the thickness applied and how well it adheres. I would think a topical sealer would wear especially fast in the areas that car tires repeatedly go over. 10 years now and my drive still looks great ( i did seal again after 7 years with same sealer) I live in an area that uses lots of corrosive road salt during the winter and no signs of pitting damage has happened to my driveway. If you do with a pentrating, sealer it is easy to apply with a pump sprayer ( need a metal one as the sealer will ruin a plastic sprayer) Beware the sealer will kill and grass/plants along the edges of the driveway if spray them.

 

[BoomerD]

Concrete takes a long time to cure. Will it cure with this stuff on it? If not, I'd wait a couple of months.

This. Concrete doesn't reach it's cured strength for 28 days minimum...and will continue to fully cure (dry internally) for at least a couple of months. Driveways are usually pretty thin. 4-6", so 30-60 days should be enough time.

 

[Red Squirrel]

I would wait at least a few months, to make sure it's fully cured. I don't know if it really makes a difference, but that would be my train of thought anyway.