So Many Question for Western WA Roof Job


I live near Olympia, WA. Need a new roof soon before refi ok’d. Got 3 estimates and trying to make sense of what I should question and or request. House is smallish and originally built in 1926. Will be a total reroof with tear off of cedar shakes. No way I can afford cedar shakes or shingles. Install Pabco or Malarkey laminate asphalt shingles. Estimates are about 25 squares and 70 sheets 1/2" cdx plywood. Only 4 roof surfaces. Front gabled roof has one side with a curved slope with other one straight. It is about a 12/12 slope at my guess (estimates don’t say). Gabled roof ridge butts into main roof about 2-3 feet below main roof ridge. Main roof sides are larger area with medium slope of about 7/12 or 8/12. Hoping for break in weather to get job done. Estimates call for 3 day job. I expect weather to be in 40s or 50s during job with at least some light rain.

  1. Should I be concerned about proper application of seal on shingles?
  2. Should contractor tarp roof overnight?
  3. Est’s include ridge vent. Should there be ridge vents on both ridges?
  4. Est’s don’t include any kind of intake vents. No soffit vents on house. Do I need edge vents or some other kind of intake vents in my climate? I don’t think a lot of older homes have them in my area.
  5. Should I have valleys with metal, shingles weaved or overlaid with top shingle cut off in valley center?
  6. Should shingles be hand sealed with heat or asphault adhesive?
  7. Does three days sound too long for job?

Well that’s about all I the questions I’ve come across in my research. Sorry for such a long post.

  1. the most important thing (and most likely thing to be done wrong) on a shingle roof is proper nailing. 9 times out of 10 when shingles blow off its because they are “high nailed”.
  2. Sometimes I tarp a roof over night but not always. It really just comes down to a judgment call. Chances of rain/what stage I left the roof at the end of the day/if its finished space under the roof/ect. Those are the factors I look at.
  3. Depends. Are both ridges the same height or is one lower than the other?
  4. Yes, if you want your ridge vent to work to its full potential then you want intake vents. This is something that many roofers overlook. Its a bit tricky to add intake vents in your situation so be sure you find a roofer that understands what I just told you.
  5. Personal preference, I like to run one side under, run the other side over them and cut the top shingles in a straight line (closed cut) but if done correctly any of the valley types you listed will work fine.
  6. Even though its winter, I wouldn’t bother hand sealing period. I never do and have probably only had to replace maybe five blown off shingles since I started doing installs on my own (I nail my shingles correctly unlike most).
  7. No, three days is not too long for a cedar tear off/ply/shingle job. I’d rather hear a someone is taking a few days to do a roof rather than throw 25 warm bodies (and many of them are unskilled) and knock out a roof in half a day. In my experiences these end up being the jobs with the highest likelihood to done poorly.


Very good, jakesler. The one question I asked about dual ridge vents needs additional details … Front gabled roof is about 2-3 feet below main ridge running vertical to front. I forgot to mention something that is likely very important: I have a 1.5 story with room, hallway, and closets running the full length of main roof. Walls and space under roof are insulated with roll unsulation (not blown in). It looks like insulation fills the 6-8"gap above the bedroom ceiling and the roof. This room splits the original huge attic space in two. Ridge for front gabled roof is not blocked at all – full empty space in that part of attic. Backside attic (other side of upstairs bedroom) is all slope up to ridge above bedroom which as I mentioned has insulation above the room ceiling up to the ridge. In this case, is a ridge vent appropriate for the main ridge for exhaust ventilation of the backside of attic? Would box vents be necessary for the back roof? Thank you very much. You and this forum have been a great help in understanding my roofing issues.


If your concerned about sealing of shingles I’d find a roofer who uses Owens Corning Duration. The Surenail strip helps prevent blow offs. I would also recommend using 3/4" plywood. instead of 1/2". I’m a Long Island NY roofing company that specializes in removing cedar and installing a new roof system. Look into using a smart vent at eaves. Proper attic ventilation requires intake and exhaust vents. Closed cut valleys is the way to go unless you are using copper in the valleys.


If both ridges are completely separated from each other in the attic than yes it is fine to ventilate both of them. If not then only vent the higher one. The reasoning is that they say the they are both vented the lower ridge could cause a “short circuit” in the ventilation system and cause it to not work to its full potential. To be honest I am not 100% I agree with that but that’s how most manufacturers call for it to be done so that’s how I do it.

Not sure exactly why you are asking about box vents on the back. Are you saying there is no ridge to vent that section? If so then yes, box vents would be an option. To work they also need an intake vent at the bottom of the section. If you posted some pics I would be better able to understand your situation.


Thanks. I mentioned box vents in case the ridge vent would be inappropriate for exhausting the back side of attic. It seems not to be the case. Essentially, I have two attics because of the upstairs room. I think I have the answers I need. Thank you all for your professional help.


Now that it’s getting time to pull the trigger on choosing my roofer, I run into another question to ask for your help. The gabled front of house has one side with a straight slope surface from ridge to edge. The other side’s surface has a concave shape. Both valleys have W metal. The side that has a straight slope has a straight valley run down to the gutter and is made of 2 pieces of metal. The concave side has 6 pieces of metal that run to the gutter and the valley curves as it runs to the gutter. See pictures. How would you handle this situation? Of course I would want both valleys to match in materials used, that is, both open or both closed.


Another question: without seeing the construction under the roof do you think the plywood could be laid down to take out the the curve of the valley? I see this as extending the concave side further into the side of the main roof.


I see no way to remove the curve in the valley without doing fairly major structural work.


Do the new valley in segments just like the old, that is a proper installation.