My meter box outside, which connects to the weatherhead, has a 200amp meter in it. Check your meter first, to see what is needed to upgrade your service to a 150 or 200amp service panel inside. If you have a 200amp meter (new digital ones are all 200 I believe) Then check the gauge wire coming into the panel from the meter. If it is the correct gauge for your new panel, all you would have to do is pull the meter, (notify the electric company of doing this) and then replace your 100amp panel with either the 150 or 200amp panel.
Menards has great sales on panels, and breakers, that is what my daughter (electrician) and I did to upgrade my home panel for the kitchen remodel with a wall oven/microwave combo, and an induction stovetop in the counter, both of which took 40 amp 220v breakers. It took a couple hours to replace the panel, re-hook all the wiring that was removed from the old panel, and connect up everything.
Now, if your meter isn't a 200amp rated meter, then you will have to have an electrician look at the service drop and weatherhead connections to the meter box, and see if you need to upgrade them too. Mine was old, but still had rated wiring from the pole into the meter, and into the panel. Yours may be also! I have about 5 or 6 unused breaker locations, as I purchased a long-a** panel to hang in place of the old one, and I can add more circuits as time goes by...
Charlie
