I have a double wide with a small enclosed porch attached. Its leaked for years along where it butts up to the house roof, and not a whole lot of pitch. I think I need to run my porch roofing under the house shingles up several rows, at ;east thats what Ive been told. Can someone please tell me the best way to loosen the rows of shingles, and properly install new roofing/flashing so I can finally have a dry porch?
Its reall bad when the snow/ice melts in the spring. Thanks so much, Doug in Pa.
I don't know much about typical "double-wide" construction. I also have no idea what "not much slope" means. You say you have shingles on the house.... are there shingles on the porch too? Typically you don't use asphalt shingles on < 4:12 pitch. Standard roll flashing is all that's required if both pitches are >= 4:12. If it's less than that you need to have a membrane of some sort (roll asphalt, hot-mopped, tar, runner, pvc, vinyl whatever) where the pieces are joined together to be waterproof. Unless the porch goes the whole length of the structure, you also have roof/wall flashing and potential leak points to check.
I'm not a roofer, and all the flat roofs I've framed I've had someone else warranty the membranes But I can tell you how to remove a standard asphalt shingle. You just need a flat bar to pry up the shingles. They're available pretty much everywhere and you probably have one lying around already. Anyway, you just loosen the tar strip that holds the shingles down by gently prying, then slide the bar up a bit and then go back and forth to find the nails, slip the notch on the flat bar under the nail and pop it up. You will probably destroy a couple shingles, so carry a few spares up with you. In fact I usually don't try to save the ones I'm removing and just take care no to damage the ones I'm not.
If you have a hard time separating the shingles from each other, your roof is at the end of its life (or it's really cold or really hot). If it's cold you can get creative to warm them up, and if it's hot this time of year you're lucky (just wait for the sun to pass). You want the tar to be pliable, but not molten.
Nailing them back down can be tricky as you can't always get your hammer in too well under the top-most course (obviously work from the bottom up). Any nails that are too low on the shingle will need to be patched with some roof cement as you basically just made a hole in your roof with the nail.
The problem with flat roofs is that wind can push water "up" pretty far, so it's not entirely a question of overlap distance as much as a good joint. So, a roof that has enough pitch to drain properly can still leak if there's a little wind and the layers of the membrane aren't properly joined. Your roof could be leaking from water going up the porch or down the roof. If it's down the roof you can also consider making a curb to divert the water. If it was me with a flat roof, I'd probably call a roofer.