comercial flatwork advice

[Craig Lawrence]

I'm looking for some advice on doing a large concrete cleaning job ( approx. 33,000 sq.ft.)I have a few questions and will explain how I intend to do the job, and would appreciate any suggestions.

I need to purchase a new hot water pw. Not sure if I should get a 3500/5.6 20hp or 3000/8.0 22hp. The job will be done with two people. I thought one guy would go ahead get up the gum and put down chemicals where needed ( some oil spots) while the other used the surface cleaner, and then someone would have to also rinse after the surface cleaner. I already have a 3000/4.0 cold water machine.
Should I buy the pw that can run two guns or should I get the smaller one and use the cold water PW to rinse?
As far as how I was going to do the job, I may be way off base. How would you do it? How long would it take you to do? With my experience how long should I expect it to take me?
After seeing Ron's pictures I sure hope this doesn't turn out looking like that. This being my first concrete job, yet we all have to start some time.
The concrete is about 8 years old and includes the whole perimeter of a Lowes Home Improvement Center.
I'm not looking for pricing information just technic and how to do it with what I equipment I have or plan to get above.
Please excuse the long post and writing skills. Craig





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[Ron Musgraves]

Graig ,

Lets talk about the equipment, either one of these machines are fine. If you just use the cold water you will need to find a chemical to assist you. If you use the cold water to rinse that’s great too. Don’t worry about the chemicals as much. Using hot water you will still need a chemical to make the job run faster and smoother.


How long will it take to do it?

This is a loaded question, if theirs not a lot of gum or paint that has been spilled. Should take about 6 hours. If theirs a lot of gum depending on how much it could take you by yourself two days. Remember removing gum properly takes time if the concrete is soft.


Concrete strength,

Commercial concrete is supposed to be 3500 pounds per inch in strength. This standard has a three and sometimes four to one ratios. However as we know some concrete is substandard. Test test test test test the area before you even bid the job. This will give you and indication on how strong the concrete is. If the concrete is good you will be able to move faster.


How to complete this job safely

1. Use a variable pressure wand. Why? So you can use the heat to remove the gum slowly with out damaging the concrete.
2. Remove gum before applying any chemicals. Chemicals can weaken the concrete and then it is more difficult to remove the gum with out damaging the concrete. Some guys will run surface cleaner so they can see the gum. I do not do this.
3. Once the gum is removed apply chemicals and run your surface cleaner over the concrete areas. Remember to rinse as you go do not let the dirty water dry on cleaned areas. Get the dirty water off those areas quickly.
4. Once the surface cleaning is done detail area with wands and get anything you have missed.
5. Caution::::::::::::::::::::::::: lowes has bags of just add water concrete on sidewalks. When they move this there will be a powder under the areas where the pallets where. Sweep this area with a broom first. If you push this powder into the parking lot it will be a nightmare. I don’t think I need to tell you what will happen. Just a tip.


Pricing,

No one can tell you how long it will take because none of us seen the job. No two lowes are going to be the same the first time you clean them. The degree of difficulty depend on how dirty they are and how much gum there is and how long its been there. Range could be from 450.00 to about 1800.00 be careful.

How old concrete is,

How old concrete is has nothing to do with anything. If its properly maintained it will clean easily.
If it’s been over 30 days it’s cured.

The main reason concrete is soft is that when installing they add water so they can move faster. Concrete is tested before they leave the yard, each and every truck goes thru a slump test. When the truck get to the job the contractors say to the driver add this much water. The driver note that load they added X amount of water. It’s not bad concrete but the contractor making it bad. Saving money, well why don’t they get in trouble because they only cheat where they know they can get away with it. Sidewalks & driveways.
I will share something really dangerous with everyone. The real reason no one goes after the guys damaging the concrete. E-mail me if you want the answer.




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Ron Marshal Phoenix AZ
1-888-fleetwash

 

[Craig Knight]

Craig,

Ron had a great reply, i will just add these two things.

Ron suggested he removes gum before running the surface cleaner. I am one of the few that run the surface cleaner first then remove gum while rinsing. No special reason besides its easier to see and chemicals and heat used to clean with surface cleaner loosen the gum where it takes a lot less pressure and alot less time to remove. Again, this is just personal preference.

On pricing, i wouldn't go less than $1650, which is 5 cents a square ft. But would shoot for around 7.5 cents/ft. Again, this price is personal preference based on overhead and how much i want the job.


Craig

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Craig Knight
www.powerwashunlimited.com

 

[Ron Musgraves]

Mr. Knight,

You are one of the many that use your surface cleaner before you remove gum. I don’t know anyone that removes gum first.

I just know that I have less chance of damaging the concrete if I remove gum first then after. If it where maintenance accounts then I guess it wouldn’t matter. The initial cleaning of the accounts are what I’m really talking about I guess I should have been more specific.

If you apply the chemical it will always be more abrasive to the concrete rather than the gum. Mean while you are taking concrete away from around the gum. The gum is still there. Chemicals that I have found that loosen gum usually soften concrete considerably. That means you spend more time taking it up so you don’t damage the surface.

Craig L,

Pricing,

If you are going to maintain the property every 15 to 30 days no one will pay you 1800.00 for maintenance. I gave a broad range because you may charge more for the initial than maintenance. Remember there is no sq. ft price you need to look at every new account and say what is the degree of difficulty. Once you have established a good eye for gum and other problems you will learn to see. Then you can set a maintenance sq. ft price that’s conformable for you. I can sit here and tell you charge 1800.00 because you can be safe, well that might not get you the job. Assess the sidewalks, ask yourself how dirty are they?



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Ron Marshal Phoenix AZ
1-888-fleetwash

 

[Craig Knight]

Ron,

Not sure what chems your using, but anything short of acid doesn't weaken concrete down here. Takes a jack hammer to pit our concrete. Been doing flatwork in Houston for 3.5 years now and never had a problem. Have had most of my maintenance contracts for over 3 years and get referrals from them on a regular basis. Initial cleaning on these contracts were tough, but damaging concrete or anything else for that matter is not in my vocabulary. Plus, if you advise the customers before commencement that with regular cleanings, the concrete will brighten as the greases and oil stains rise to the surface, they will understand that it will only look better in time, and you dont have to use damaging chemicals on initial cleaning.

I know your advising the newbies a safe and effective route to take, and thats a must. Keep up the good work.

Craig

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Craig Knight
www.powerwashunlimited.com

 

[Ron Musgraves]

Telling guys this over Ten years ago, Still telling guys to

Graig ,

Lets talk about the equipment, either one of these machines are fine. If you just use the cold water you will need to find a chemical to assist you. If you use the cold water to rinse that’s great too. Don’t worry about the chemicals as much. Using hot water you will still need a chemical to make the job run faster and smoother.


How long will it take to do it?

This is a loaded question, if theirs not a lot of gum or paint that has been spilled. Should take about 6 hours. If theirs a lot of gum depending on how much it could take you by yourself two days. Remember removing gum properly takes time if the concrete is soft.


Concrete strength,

Commercial concrete is supposed to be 3500 pounds per inch in strength. This standard has a three and sometimes four to one ratios. However as we know some concrete is substandard. Test test test test test the area before you even bid the job. This will give you and indication on how strong the concrete is. If the concrete is good you will be able to move faster.


How to complete this job safely

1. Use a variable pressure wand. Why? So you can use the heat to remove the gum slowly with out damaging the concrete.
2. Remove gum before applying any chemicals. Chemicals can weaken the concrete and then it is more difficult to remove the gum with out damaging the concrete. Some guys will run surface cleaner so they can see the gum. I do not do this.
3. Once the gum is removed apply chemicals and run your surface cleaner over the concrete areas. Remember to rinse as you go do not let the dirty water dry on cleaned areas. Get the dirty water off those areas quickly.
4. Once the surface cleaning is done detail area with wands and get anything you have missed.
5. Caution::::::::::::::::::::::::: lowes has bags of just add water concrete on sidewalks. When they move this there will be a powder under the areas where the pallets where. Sweep this area with a broom first. If you push this powder into the parking lot it will be a nightmare. I don’t think I need to tell you what will happen. Just a tip.


Pricing,

No one can tell you how long it will take because none of us seen the job. No two lowes are going to be the same the first time you clean them. The degree of difficulty depend on how dirty they are and how much gum there is and how long its been there. Range could be from 450.00 to about 1800.00 be careful.

How old concrete is,

How old concrete is has nothing to do with anything. If its properly maintained it will clean easily.
If it’s been over 30 days it’s cured.

The main reason concrete is soft is that when installing they add water so they can move faster. Concrete is tested before they leave the yard, each and every truck goes thru a slump test. When the truck get to the job the contractors say to the driver add this much water. The driver note that load they added X amount of water. It’s not bad concrete but the contractor making it bad. Saving money, well why don’t they get in trouble because they only cheat where they know they can get away with it. Sidewalks & driveways.
I will share something really dangerous with everyone. The real reason no one goes after the guys damaging the concrete. E-mail me if you want the answer.




------------------
Ron Marshal Phoenix AZ
1-888-fleetwash