concrete slopes fro drainage

[scottklempke]

Question: What are industry standards for sloping concrete (exterior) slabs to create adequate water runoff?
Valley Gutter slope? (being extremely limited would .75% be adequate?) what about acceptable concrete flateness tolerances whenso little slope is demanded?

any comments?

 

[jimbo]

scottklempke

There are no "industry standards" in my opinion. It depends on to whom you are talking. Many government agencies in my area [Michigan] use 2% transverse slope on road pavements. That is frequently inadequate in my opinion. Pavement sinks and gullies, and water lays on it. Splashing, ice and difficulty stopping are the result.

In a valley gutter where water may lay (and cause no physical problem) I have used less than 1% slope. If ice is a problem, that is a problem to be eliminated.

I have seen engineers try to run water on asphalt pavements at 1%, ALWAYS with no permanent success.

Buy a dictionary, keep it nearby and USE it. Webster's New World Dictionary of American English is recommended, and Webster's Collegiate Dictionary.