If brides want IMBC for outside wedding in middle of Aug (temp 80Fto95F)
How can I answer to her? Do you recommend BC?
I know it is going to melt if it let sit for hours.
Keep the cake inside AC room as long as possible,then take it outside for
the cake time???That is how to do?
Does anyone do IMBC for summer outside party?
Thank you.

No, don't do it! It will completely melt and you'll be to blame. I'm in the same situation - I have an outdoor wedding in August and it could be 95-100 easy up here. My cake will be in a tent but not a/c and it is fondant thank goodness. I usually use white choc ganache under the fondant but I don't think that will hold up either so I think I'm going to go with a thin coat of IndyDeb's frosting recipe even though I'm not a ps icing fan. I love IMBC but there is NO way if the temp is going above 75 that I would risk it.

Ask her what happens to a stick of butter in 85-90 degree temps? Well, that is what is going to happen to the icing on her wedding cake. Sorry to be the bearer of bad news but it was their decision to have the cake outside.

Make sure that your contract says that it is their responsibility to provide a "safe" environment for the cake, ie. reasonable temperature. Then they do it at their risk, not yours.

HTH

I agree, IMBC just won't hold up in heat. The last cake I did with IMBC was in Nov. and it was still a little warm where I live, FL. I use sugarshacks recipe for buttercream if it is hot. It holds up great in heat.

The whipped cream buttercream found in the recipe section here is heat stable. There's no cream in it.