I am trying to add a shed on to my chicken coop, which is already known to family and friends as the goat shed (in honor of its future use). The problem is that it has a standing seam metal gable roof and I need to go part way up to hook the new shed style roof on, about 4-5' up to get enough pitch. At first I thought of cutting off the bottom metal, nailing the new rafters into the old and slipping the new flashing under the old metal and onto the new corrigated metal roof. Then I realized this wouldnt be a one day job and that it would leave my chickens vulnerable overnight, there would be a hole in the gable end wall that would be hard to block up temporarily. So then i thought about nailing a 2x4 to the old roof parallel to the ground and nailing the new rafters to it, leaving the old roof intact. I cant figure out if there a way to flash from the old to the new roof. My neighbor suggested to notch the flashing to fit over the standing seams a little better and use a whole lotta tar. I am hoping this is making sense, kinda hard with out a picture to explain. Any ideas? My new motto is the hardest part of any job is getting started, from there its all down hill. Thanks, Tami in WI

-- Tami Bowser (windridg@chorus.net), May 15, 2000

Answers

Tami, being an "old retired roofer" I've done my fair share of flashing jobs and must say your original idea was the correct one. Why not just buy some plastic tarp and cover the roof at the end of the day while you work to finish it? It won't take as long as you may suspect it to. That old tin roof is fairly easy to cut and pry up: it'll go more quickly than you think (just be careful not to cut yourself). I surely wouldn't do the "notching" thing, that will be trouble forever! Why do you need to go "up the roof" to tie on the new shed? Pitch? Anything under your new roof will be lost space anyway until it clears the old "goat barn's" roof. If you can use one piece of corrigated roofing, there would be no seams for the water to back up and leak through...just a bit of pitch would be enough for run off. I would overlap the sheets by at least 2 ridges tho. Wait a month and coat the new roof with some roof coating to help preserve it. Use "metal" roof screws to secure it, not the washered nails.

Hope this helps. Feel free to email me if you have any questions.

-- Jim Roberts (jroberts1@cas.org), May 15, 2000.

Would it help to dig the floor of the addition down a little deeper than the original building? That way maybe you could attach the new shed roof at the original eave line and not have to cut the old roof. And Jim is right that you won't need much pitch on the new roof to shed water -- what about snow load, though?

-- Kathleen Sanderson (stonycft@worldpath.net), May 15, 2000.

I got a little carried away with the thought of the addition and made it 12-14' wide I cant remember which. The old wall just under the eave is just under 7'. I figured that by the time I dropped it down enough for that wide of a roof that my husband who is 6-2 would be knocking his head on it, especially with any manure/bedding build up. Considering that I am in WI, what would the suggested pitch be(with snow load)? I hadnt thought of digging it out. The problem I see with tarping it would be that possibly a racoon would let it self into my chicken coop for a snack during the night. Thanks for the hint with the metal roof screws. I didnt know that there was such thing-do they have washers too? Thanks Tami

-- Tami Bowser (windridg@chorus.net), May 15, 2000.

Metal roofing screws: Yes, hard, rubber washers. They are also really sharp and fairly easy to start. They are hex head and would require a socket for your drill/screw driver. Hadn't thought about the snow-load. I live in central Ohio and that isn't a problem here.

Hint II: In case you don't know this already, if you do decide to cut into the old metal roof, put your standard circular saw blade in backwards...it cuts the metal or aluminum better that way, more smoothly and with less bucking.

-- Jim Roberts (jroberts1@cas.org), May 17, 2000.