Short deadline rate increase

Hi everyone.

I have an ethical question for you, and I could use your advice.

I have recently ceased work at my web dev job and they will become a client of my business. When giving them my rate at which I do work, I'm not sure how to account for a short deadline or work that needs done quickly.

Has anyone else had to deal with this? If so, how did you go about it?

My main concern is that a company could be possibly "penalized" for a lot of projects simply because they get work from one of their clients that needs done quickly. They get the work, then contract that work to me and because I have a short deadline clause, they get penalized. I want to create an atmosphere of comfortability both ways without getting nailed with work that needs done in a day.

Any suggestions?

-B