Footings

The ground freezes up to a depth of 42 inches in the Twin Cities area.  Therefore your footings must be at least that deep or ice will form under them and cause frost heave.    Furthermore, the wall of the footing must be smooth so that ice won't grip it and move it up with leverage.  And most important, the base must be sized according to the weight of the load, including potential snow load. This is accomplished by belling out the bottom of the hole and tapering the column into a smooth tube.   The city building official must inspect for these factors before I can pour the concrete. Once the footing is hardened, metal connections join the wood to the concrete in a manner that will not sway, stray, or wick up water into the wood. Requirements for future 3-season porches or screen porches: increase corner footing size by 90% locate all footings at extremities of deck (no cantilevers). increase center footing size shown by 55% beam sizes indicated need not be altered The utilities will have been marked prior to digging whether you think there are any back there or not. This is a state law.   I will take care of making it happen, and you will have little temporary lines painted on your lawn.