Mining is still profitable if you are in the right situation or willing to put forth some effort.
Do you have cheap electricity? If not move to some where that does or look at renting a small office to get commercial rates.
Do you have access to miners? If not you will need to buy miners at good price to make ROI easier, used miners are your best choice.
Do you live in a cold climate? If not you will need money for fans, cooling, the power to run them, etc
Do you have the electrical infrastructure? If not you will need money for outlets, wiring, breakers and possibly more
Once you figure all this out you can use a calculator to figure out if you will hit ROI. Mining is still profitable but it takes effort and possibly a little luck on your current facilities.
this past winter i did this with some s1's, power cost here is only 0.03/04 so it was worth while
That is some cheap electricity you have there!
I would suggest not directly using miners as heaters. I think there was some discussion on it here on bitcointalk (something like how to use your old miners or similar) that it may not be the best idea as heating circuit boards may give out some fumes that are not particularly healthy. If you want to do it "properly" you could use a heat exchanger system. You could even build one for yourself if you are into a bit of DIY!
Although of course, it would only make sense investing more if you were planning on using it for multiple years. Nevertheless, its a good use and combination of multiple systems.