It is always better to repair the chimney prior to any roofing work. This way the new roof doesn't get damaged.
Proper ventilation is extremely important for a long lasting roof. If you roof is sweating and creating condenstaion it can deteriorate your entire roofing system from the decking and supports to the underlayment and shingles. Also, depending on your climate, inproper ventilation will contribute to ice dams. I'd recommend cutting in a roof long ridge vent as soon as possible.
Hey Terry,
Black spots on the roof usually form do on the Northern facing side of the home because it has less direct exposure to sun light.
Blue-Green algae is usually what the black spots are, however, depending on the age of the roof, sometimes the loss of granules also shows black streaking, which can be a sign that the roof is nearing the time for replacement.
BBB is a great place to leave reviews. I would also send a private email to the business or contractor you have the complaint with. That way they are aware of how you feel and the concerns you have. If you leave w public review on Google or yelp for example Be careful with wording. Everything left on a review must be factual and able to prove just. Freedom of speech becomes libel or defamation of character. If the contractor looses business or potential customers directly because of the review you could have legal trouble assuming they can prove negative impact.
In twenty years it only came up once. It was an old house and the owner knew it was substandard. It is taken for granted by most people that a house was built to code and still in sound condition. It would seem logical then if you put the same riding material on the house everything should be alright. There not enough inclination here to even guess what went wrong but you need to get a licensed, or at least certified inspector, and another reputable roofer to evaluate the installing and structure to determine Weiss at fault.
The best way to fix and resolve ice dams is actualy proper isulation in the attic space. Next is proper ventilation. Both intake and exhaust. These are critcal but rarely done correct and very costly and hard to do rero.
If the above are not done then a good qulity ice melting system is best. Either a commecial grade heat cable/heat tape or an ice melting system such as a heat panel.
Never use a continous watage cable as they are not safe or effecient.
Only use a self regulating cable as they are safe and effecient.
You will want the cable in the gutters and downspouts first, the next step is cable in the valleys and lastly weaved on the roof.
Here are a few ideas....
Using the information you have provided and not visually inspecting the roof, the black spots on your roof are more than likely algae. Most shingle manufacturers use copper or zinc coated granules to aid against the growth of algae. As the rain washes over your shingles, particles of the copper are dispersed helping the prevention of algae growth. Most manufacturers warranties will cover the first 10 years against streaking and staining, which helps to explain why you have not seen evidence of this issue before. There are low pressure solutions available to clean your roof but they will not prevent the stains from returning. The addition of copper or zinc strips under the first full course of shingles below the ridge cap could provide to be a longer lasting remedy. I suggest that you contact a reputable local roofing contractor for a complete roof inspection before you make a decision on the remedy, as the algae can hold moisture and can prematurely age your shingles. ( Damon Ward Project manager At Allstate Exteriors llc.)
There isn't a lot of information, so I'll make some assumptions. First the black "spots" are on the inside of the roof sheating, the black spots are assumed to be mold and you live in a cold climate?
If my assumptions are correct you probably have inadequate ventilation of the attic area causing moisture to accumulate, condense and probably freeze during cold weather (hence the spots being limited to north side where sun does not directly heat roof in winter) This water probably thaws in the spring and leaves enough moisture at the surface (water activity) for a long enough time with sufficient temperature to allow mold (probably Cladosporium) to grow.
This is probably either as a result of a moisture source, such as a bathroom vent or perhaps ambient moisture escaping the finished area at an attic access, can lights, etc. I suspect when you added the insulation, the temperature of the attic space was lowered during heating season as less heat was lost to the attic from the finished space.
Probably need to verify that there are no sources adding moisture load to attic, then add or increase the size of the venting or add a humidistat activated exhaust fan to the attic space to correct the cause and then properly remediate the (apparent) mold.
If the spots are on the outside, the addition of insulation may still have changed the balance of the attic temperature, resulting in moisture staying on the roof longer than in the past as the roof is not heated and dried as quickly by the "lost" heat from the inside. This may mean it is becomes a maintenance issue either by addition of a controlling agent in or on the roofing material or (annual) cleaning to remove the "spots" when they appear.
We think this is a great blog on ice damming and the need fir insulation.
http://www.callenblog.com/keeping-attic-heat-and-moisture-under-control
Good luck.
Home Exteriors by Callen
One easy way is to simply go into the attic space and look around and see if there is any staining on the underside of the ply wood. The most common areas are around pipe and chimney penetrations, in the valleys or where the roof terminates into a wall. If your roof is walkable, and you feel comfortable enough to get up there, you can also use a garden hose and attempt spraying the roof from different angles to see if any water gets through. Over all though, if you see any discoloration at all, then water is penetrating some way.
Hey William,
I would say your best bet is to shingle over the vents and edge the vents at eaves. This way you are able to allow for intake and continuous ridge vent for exhaust. Hope this helps!
Eric Consuegra
AROCON Roofing and Construction, LLC
If the space behind the knee wall is clear from end to end and you install gable end vents at each end then that would keep the eaves from freezing and causing ice dams.Make sure the knee wall is well insulated. You want to keep the heat in the finished area and get the space behind the wall as cold as it is outside.What you need to do is create some convection in there. If you don't want to spend the money for this then you could try a high powered exhaust fan for one of the roof vents and try to get some air movement from that.
Hi William,
Have you looked into ridge vent? Do you know how many LF your ridge is?