New Roof Time

[VCFD]

Well, it's time for the next project! I had some serious ice dam and water damage throughout my house over the winter. I replaced all of the ceilings with 1/2" drywall and new insulation. I would of replaced the roof first but mother nature wouldn't allow it so instead of waiting I decided to do the inside first.

I've been reading all of the threads about roof overs and such but with 2 layers of shingles on already, I've decided to tear them off so I can put down ice a water shield across the entire roof. There doesn't appear to be any boards that need to be replaced but I will if needed.

My question is about ventilation and whether I should go with a metal or shingle roof. There are currently 6 12" vents. Should I/could I remove them and put in a ridge vent? There are 6" soffit vents at the eaves and approx. 12" at the ends.

I posted a few pictures in my album. Thanks1

[Jim from Canada]

What you use for the covering will depend on the slope. Most low slope like mine (2/12) will require shingles. I believe that a metal roof requires a pitch of 4/12 or greater, but check your codes and manufacturers recomendations. It is an excellent idea to put ice/water shield over the whole roof even though code only requires 3 feet. Ridge vents are also highly recomended especially if you have cathedral ceilings. If not, make sure to put foam baffles on the roof over the walls. These ensure airflow over the top of the insulation to the ridge vent. The eaves at the gable ends do not need to be vented.

Jim

[geraldk]

judging by your pic of outside the home you have a fairliy low pitched roof...the soffit seems a bit to small for good venting.. my self i'd use metal and get the snow sliding off faster maybe build a pony wall of sorts down the ridge and new joists down to the edge and get more pitch just another idea id try

[geraldk]

one more thought maybe your insulation is too high near the top of your outer walls and cold air getting in the soffits is getting trapped there an causing your icedaming just one more thing to looki at if your taking off shingles and sheeting

[VCFD]

Thanks for the responses. I will take a measurement and determine the slope. I'm hoping it's at least 3/12. I'd rather go with metal if I could. I will definitely put in a ridge vent as well. When I did the new ceilings and insulation, I also added the foam baffles over the walls, so I should be OK there.

Thanks.

[JD]

What a beautiful place. There has been a lot of work put into the home to give it that cabin/lodge look. It is possible that who ever did this work also installed edge piers or outriggers, or something to shore up the walls. The split log siding, upgraded paneling and 2 layer roof is a lot of weight.

The ice & water shield over good sheathing is a good choice whether you go steel or shingles. But I am thinking that the shingles is part of the water damage problem. The rest of the problem is in the venting and insulation. Coming up with a design that will minimize the ice damming should be the goal. I think what is happening is, the ice dam will cause melting water to travel sideways as it reached the dam at the eave. When water travels sideways on a shingle roof, it will leak. Ice & Water Shield will help to keep the water from getting to the sheathing. To help eliminate that problem, some sort of standing seam metal roof might be the answer.

I am not going to comment on the venting issue, because I have no experience with roofs and snow. It is very rare for snow to fall in the Fresno, CA area, and it certainly won't stay on the ground more than a few minutes.

JD

[VCFD]

Thanks JD! Yes, the previous owner had a lot of work done to give it that cabin look, but from what I'm seeing and all of the problems I've been having most of the work was sub-par. That is alot of weight on the walls and siding but they appear to be in good shape.

The current roofing has no ice shield at all. I think they put the second layer on to try and stop the ice damming. Obviously, it didn't work.

What exactly do you mean by "standing seam metal roof"? I've been researching different metal systems but I haven't come across that term yet.

[JD]

A standing seam is an engineered metal roof panel. Basically like corrugated metal with a different design. These are the type of metal roofs you see in snow country. The whole idea is with the seam/connection of the panels being raised off of the roof, the water runs down the face of the panels away from the seams. In these pictures, water would have to build up 1-3/4" to 3" (depending on panel used) before the water could leak in that area. I got these examples doing a quick search of Standing Seam Roof, just to snag some images to show you. A quick glance at the specs on these panels seamed like they were pretty good products. But there are many manufacturers. You could do a search with your city name in it to see who would supply your area. I noticed that one of these products said it could go on a 1/4" to 12" pitch. That is very cool. But do the research for products available to you, to see what is best for your snow area.

JD

[JD]

Forgot to include the links to the websites where I found the images. Explore the rest of the web sites below for other panel options. Then look for other companies that make products like these for your area.


DESIGN SPAN HP
http://www.metaldeck.com/design_span.html

MASTER-LOC 90
http://www.mcelroymetal.com/content/pro ... duct_id=15

[VCFD]

Thanks for the help JD. That's great information. I'll make sure I check it out!

I just spoke with the code enforcement officer for the town and he told me there are no restrictions on using a metal roof so I'm free to use whatever design I want.

[Jim from Canada]

If you are re doing the roof you might want to extend the eaves a few inches as part of the project to aid in venting.

Jim