considering adding on a porch to the front of my home. house has a hip roof and existing concrete pad now. would like to make the roof the same type has the house. will the roofing and sheating need to be removed on the area of the existing house roof to tie in the new one? Can i anchor posts to the existing concrete to support the new roof? or will the existing concrete pad need to be removed? The planned porch will be approx 8 to 9 feet off the front of the house and approx 16 feet long. my big concern is causing a leak in the roof and not attaching and supporting it properly. any guidance will be very much appreciated.

You will have to cut into the existing roof to tie in the new roof. There are several different methods to do this, usually all will have you create a valley in either side of your new hip roof on the porch. If your existing house shingles are in good condition, then you can cut the existing shingles at the valley location and use a metal valley flashing piece to channel water. Otherwise, you can make a case for re-roofing all or a part of the existing house so that you can weave the valley area between the house roof and the porch roof.

At the bottom end, your existing pad will not be enough to support the porch structure. You may not have to remove all the pad, but you'll have to cut out wherever you have support posts so you can pour a proper sized footer.

Building a porch is a fairly large project. That, plus it will be the focal point of the front of your house. If you are unsure hot to do all the steps, it would be a good idea to get some professional help.