Grout cleaning with metal brush

[Predict]

Sorry if this is wrong catagory. I didn't see a tile and grout catagory.

In my experience in cleaning grout I been trying a metal brush off and on, and at first got scared of using it in fear of damaging the grout. In time I learned that if I'm gentle with the brush it is safe, but I've been noticing that there are different kinds of grout. Some I can brush with this metal bristle brush and it cleans it very very well. Then there are some grout that's very brittle and I can see it damaging the grout. As if I'm sanding it down with each brush stroke.
Now I wonder if it's because one grout is a cheap brand or is it because of the thickness of the grout? Why is it that one grout I can brush no problem and another crumbles with each stroke?

 

[PistolPete]

Sorry if this is wrong catagory. I didn't see a tile and grout catagory.

In my experience in cleaning grout I been trying a metal brush off and on, and at first got scared of using it in fear of damaging the grout. In time I learned that if I'm gentle with the brush it is safe, but I've been noticing that there are different kinds of grout. Some I can brush with this metal bristle brush and it cleans it very very well. Then there are some grout that's very brittle and I can see it damaging the grout. As if I'm sanding it down with each brush stroke.
Now I wonder if it's because one grout is a cheap brand or is it because of the thickness of the grout? Why is it that one grout I can brush no problem and another crumbles with each stroke?

Multiple reasons. Poorly mixed, poorly installed, age, cracked or damaged.
Get a grout demon brush and save the metal brush for rare cases when you need it.

 

[Blacktiedetailing]

Why are you using a metal brush? 7 years and only used a grout brush once and that was behind a toilet. Never a need to use a grout brush if you use the proper chem, heat and pressure

 

[Predict]

I use grout master from here, and shark brush, around 1200-1800 psi. I'll agitate let the chemical sit for 15 minutes then go over it with the hydro Force. Then I sometimes need spots that don't come clean right away so I lightly scrub with metal. The metal brush also works great in corners that are hard to reach.

 

[Predict]

Why are you using a metal brush? 7 years and only used a grout brush once and that was behind a toilet. Never a need to use a grout brush if you use the proper chem, heat and pressure

I must use a brush. When I don't dirty spots get left behind. I use grout master. I mix it extra strong, but most of the time it inky gets 80% of the dirt out of the grout.

 

[Dafloorman]

I must use a brush. When I don't dirty spots get left behind. I use grout master. I mix it extra strong, but most of the time it inky gets 80% of the dirt out of the grout.

We use the soft black brush, also the spots that are left behind, sometimes would need to be hit with a little acid. Sometimes we use no brush at all, many times the turbo tool will get up everything. Also we do color sealing, not all floors are going to go back to their original color, hence the need for color sealing.

 

[Predict]

We use the soft black brush, also the spots that are left behind, sometimes would need to be hit with a little acid. Sometimes we use no brush at all, many times the turbo tool will get up everything. Also we do color sealing, not all floors are going to go back to their original color, hence the need for color sealing.

I agree with this. I do color sealing also but most people in my area don't want to pay that much. The metal brush will get out everything left behind with little pressure. I also use hard bristle brush and soft black one.

But main question was I was being concerned about leaning about the grout. Why some is so brittle and some strong. The metal brush shouldn't be tearing the grout apart.

 

[Todd the Cleaner]

I agree with this. I do color sealing also but most people in my area don't want to pay that much. The metal brush will get out everything left behind with little pressure. I also use hard bristle brush and soft black one.

But main question was I was being concerned about leaning about the grout. Why some is so brittle and some strong. The metal brush shouldn't be tearing the grout apart.

I think improper mixing is the main reason. I went into a job one time where the grout was as soft as sand. You could easily dig a hole with your fingernail. I passed on that job, had I cleaned it there would have been no grout left when I was done.

The golden rule that applies to all aspects of our business is “ALWAYS TEST FIRST”.

 

[Todd the Cleaner]

Why are you using a metal brush? 7 years and only used a grout brush once and that was behind a toilet. Never a need to use a grout brush if you use the proper chem, heat and pressure

Yup, here’s a job from last week. No scrubbing.

 

[Dafloorman]

Yup, here’s a job from last week. No scrubbing.

Do you use GM Todd?

 

[Todd the Cleaner]

Do you use GM Todd?

No

 

[[email protected]]

Great job Todd. Could you include what chemo you used...ratio of chem...what psi and what temp was heat...
Thanks

 

[Scott W]

The reasons mention for soft grout have all been correct. But one more I see often is that the grout has been cleaned with an acid cleaner that was not rinsed well. Acid softens grout over time.

 

[Todd the Cleaner]

Great job Todd. Could you include what chemo you used...ratio of chem...what psi and what temp was heat...
Thanks

Usually I use Groutmaster but I’m out of it right now. I was using the powdered viper venom from Interlink, 5 scoops into a 2 gallon pump up sprayer. If I’m using Groutmaster I use 3 scoops for a 2 gallon sprayer.

I presprayed and let dwell 10 minutes then cleaned with the turbo hybrid at 1200 psi. With the high volume of water used I’m usually getting 120-130 degree water when I’m doing tile. I honestly don’t think heat makes a whole lot of difference on most tile. Restaurants are an exception.

 

[Blacktiedetailing]

no dwell time here, spray and go at 1200-1500 psi. done...

 

[zigdog]

Hey Predict. As mentioned above there are many different reasons that grout can be soft and flaky. I'm going to list a few here to make a point and to answer your question about why it can happen.

Improper water to powder ratio when mixing. Too much will dilute the cement in the grout and lead to weaker grout. Too little will not allow proper chemical reactions to occur and will lead to weaker grout.
Not allowing mixed grout to "slake" before applying. You are supposed to allow grout to sit for a few minutes after mixing and before applying or you are not allowing enough time for optimum curing process to begin.
Grouting on a day when its too hot or windy. This will dry the grout prematurely leading to improper curing.
Using too much water when cleaning excess grout after spreading which will wash the cement out of the grout.
Bad or old batch of grout used.
Not covering the floor after grouting so the the water in the grout won't evaporate too quickly and cause weak grout.
Etc., etc., etc.

This list is by no means complete or comprehensive. You should read the instructions on a bag of grout sometime for your own education.

The point is that grouting is rarely (if ever) done per manufacturers recommendations. Guys on most jobs are under a lot of stress to finish up as fast as they can, or just plain don't get paid enough to take the time to do it right and/or don't give a dang. And the reason for soft grout is really not all that important to you as someone who is only there to clean it. Truth is that you usually can't tell what the reason is after the fact without some kind of lab analysis.

Like Todd said "ALWAYS CHECK FIRST" Assume on every job that there are problem areas. Always take a tool like a knife or screwdriver and check the grout in a bunch of spots throughout the job to check for soft grout. The grout on the same job could have been applied in different rooms at different times of day by different guys or with different batches on the same job, or whatever, meaning it could be hard as a rock in the bathroom and like sand in the kitchen. It's part of your job to identify the problem areas and inform the customer before starting.

 

[[email protected]]

Thank you Todd

 

[Predict]

Thank you guys for all helpful information. I use grout master. I'll. Mix it one or two extra scoops than directions say. Spray with hydro Force sprayer. Soak it good so it doesn't dry up. Scrub a bit with nylon brush. Then use about 1500-2000 psi with Everest. What I don't see coming out I brush more with nylon or maybe get corners with metal brush. Heat usually doesn't keep up so its always low. I also run the Everest on low or medium and still reach same psi.
Most of the time grout comes clean especially after brushing. Also more than 50% of the time the grout is brittle and flakes so then I turn psi down and more careful. But I rarely get away with no brushing.