Add IFBLANK (or similar) with Formula

I have this formula currently =IF((D5+30)>TODAY(),"",(H5+I5)) it works but leaves "Value" right now if I have not populated any information so I want to add to the formula a IFBLANK(B4) adder but can't seem to figure out how or where to do it in the formula. It's not working no matter how or where I try to do it.