This is a trick used by concrete finishers for a long time; at least
30 years that I know of. Lots of others' experience tends to validate
this, but I haven't used it.

Detergent isn't an approved admixture; however, the approved ones cost
a lot more.

The theory is the detergent allows the fine aggregates to slip around
more, making it easier to finish and to consolidate around
reinforcement and forms.

If the mix is designed for the application, you shouldn't need to add
detergent. If the mix sits in the truck too long, drivers tend to add
water to "hide" the loss of plasticity. Detergent may do the same
thing. If you accept this, you're not getting what you paid for.

On Apr 12, 4:13 pm, " wrote:
Greetings,

I was told by a friend that you should always put a small amount of
liquid dish detergent into your concrete or stucco mix to make it more
workable with less water.

a) Does it actually make the mixture more workable?
b) Does it decrease the strength or increase the strength due to the
need for less water?
c) How much should you put in?
d) Anything else I should know? Perhaps it is against city code
because it isn't an "approved admixture", etc?

Just hoping for some verification or denial.

Thanks!

PS: I understand that you can purchase superplasticisers but that is
beyond the scope of many small projects such as rebuilding steps,
stuccoing a framed in porch, etc.