First of all, you should make sure that your concrete patio will be able to support the weight of the new deck. If the concrete is only 2 inches thick, it could crack under the weight of the deck, and then you would have major problems with your deck sagging/collapsing. The best way to do this is to cut holes in the patio with a concrete saw and dig 9 inch holes below your frost line (if you are in freezing climates) or 36" if you are not in freezing areas and have fairly decent ground. Then fill these holes with concrete, making sure to put an anchor bolt in the center. You can then use a "post base" (which you can find at most DIY centers (homedepot, menards, etc)) to attach a post from your deck.
If you don't want to go thru the above mentioned hassle, you can either TAPCON a post base to your existing concrete patio, or use a RAMSET (that uses a 22 caliber round to shoot a nail into the concrete).
If you don't want to go thru the above mentioned hassle, you can either TAPCON a post base to your existing concrete patio, or use a RAMSET (that uses a 22 caliber round to shoot a nail into the concrete).
