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Hi, I am in the process of getting tenders for my roof and I'm getting a lot of conflicting advice from a few roofing companies. I have a few questions that I would like to get your feedback on. This will allow me to distinguish between a legitimate roofer and the ones to avoid.

A little bit of background info, I live in British Columbia, Canada ;where it rains frequently in the fall and winter and its usually sunny in the summer time. No hurricanes or tornados in the area.

I have decided after a bit of research to go with the Malarky Harmony 30 year shingles.[/

1. For I & W membrane, how far up from the gutter lines should the membrane extend. My roof extends about 1 foot from the the walls along the gutter line.

2. Should there be an I & W in the valleys if so how far should it extend. Would you put and I & W on the sides of the roof where it meets the wall and how far should it extend. Any other places where an I& W may be beneficial.

3. I have an awning that is attached to the back of the house and the flashing goes 6" under the shingles and sits on the plywood sheath. Should the I & W membrane go on the plywood first and then have the flashing sit on top of the membrane with the new shingles on top of the flashing or should the membrane be attached over the flashing. What is the best method to prevent leaks?

4. For the valley, what is the proper method of preventing water leaks in the valley. Do you put down an I & W membrane, any other underlayment required. How are the shingles put down in the valley- do they cover the membrane or are they shingled upto the membrane and then a W-valley flashing is installed over the membrane. ----I have gotten quite a few different responses.

5.Prep prior to installing the roof- what is the best method regarding old nails in the plywood, do you pound in the old nails or do you pull them out? What are the pro and cons.

6. how far should the starter shingles be over the drip edge?

7. I am using the 15lb felt as my underlayment- does the felt go on top of the I& W membrane or does it start at the edge of the of I& W.


thanks in advance- I realize there are a quite a few questions but I would appreciate any input or any other suggestions.
 

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1. For I & W membrane, how far up from the gutter lines should the membrane extend. My roof extends about 1 foot from the the walls along the gutter line.
At least 24" inside the living area.

2. Should there be an I & W in the valleys if so how far should it extend. Would you put and I & W on the sides of the roof where it meets the wall and how far should it extend. Any other places where an I& W may be beneficial.
18" to each side, minimum.

3. I have an awning that is attached to the back of the house and the flashing goes 6" under the shingles and sits on the plywood sheath. Should the I & W membrane go on the plywood first and then have the flashing sit on top of the membrane with the new shingles on top of the flashing or should the membrane be attached over the flashing. What is the best method to prevent leaks?
In your area, I'd go under the flashing, onto the awning, then on top of the flashing. (overkill)

4. For the valley, what is the proper method of preventing water leaks in the valley. Do you put down an I & W membrane, any other underlayment required. How are the shingles put down in the valley- do they cover the membrane or are they shingled upto the membrane and then a W-valley flashing is installed over the membrane. ----I have gotten quite a few different responses.

Hope this helps. It has some do's and don'ts.

http://www.albertsroofing.com/Valley%20Details.htm

This area where most of these pix were taken gets 60" of rain and 3-4 tropical storms/hurricanes each year.

5.Prep prior to installing the roof- what is the best method regarding old nails in the plywood, do you pound in the old nails or do you pull them out? What are the pro and cons.
I remove nearly all.

6. how far should the starter shingles be over the drip edge?
I prefer 1-1/2". Other factors such as gutter, for iinstance will cause me to modify that at times.

7. I am using the 15lb felt as my underlayment- does the felt go on top of the I& W membrane or does it start at the edge of the of I& W.
From what I've seen of shingles sticking to it, I'd cover it with the felt. Just saves time and money down the road at next tear-off.
 

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I agree with Tinner on all counts except for #6, the overhang. With asphalt shingles we usually have an overhang of 1/2"- 3/4". Anything over an inch usually starts curling over the edge and later breaking off.
Less than 1/2" usually shrinks up and doesn't cover the edging. Less than 1/2" on eaves and the water will run on the fascia.
 
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