TOPIC: Roof: How hot is hot? Question concerning a ranch with no attic

Here is the situation:
I was inspecting a ranch style home with no attic.  The black roof is about 4 years old.  I found the old roof underneath.  The new architectural roof is forming to the old.  I decided to get a temp reading from the ridge vent.  That reading was 155 degrees on an eighty degree day.

I then looked at the vented vinyl soffit that was added at some point on both sides of the roof structure (East and West sides).  I could not tell if there were blocked soffit vents, or if the old vents were ever removed, or if a 2" cut was made along the old wood soffit before the new vented vinyl was installed.  I decided to try using my smoke stick to see if I could get a sense of draft (it was a mild, calm day).  The smoke just drifted around, but never up.  I moved along the entire system with no success.

I am wondering if 155 degrees is far too hot for a black double-tiled roof on an 80 degree day?  Also, does anyone have a non-destructive test for discovering a soffit with no attic?

where do you live Mike , it is common in the summer to have attic space at that temp & does this roof have a ridge vent

Hi Dennis:
The house is about 1 hour southeast of Buffalo NY in Ellicottville.  As I mentioned, I did take a reading from the ridge vent.  I was surprised at the amount of heat.  My main interest is to figure out if the soffit is drawing.  I did forget to note there is one gable vent on the North side of the house.  I am suspicious that there is not enough venting for the square footage of the roofs.

www.buildingscience.com/documents/digest...ng-attic-ventilation

Mike,

I haven't gotten my mind wrapped around your description of the house. You said it is a ranch with no attic?  Is it a two story gable or a low slope?  I hear ranch and all I see is a one story with a gable or hip roof.  I haven't ever heard of a ranch with no attic and I think the composition of what is directly below the surface of the roof would greatly influence your question.  Sorry for the confusion, just need a little clarity.  Thanks.

Cameron, I have the same thoughts. I am envisioning vaulted ceilings, perhaps throughout the entire home. Any areas (over bedrooms) for potential attic space may be sealed (no access).

Also, if the temp. that was taken, was actually of the roof surface (asphalt shingles)?

More specific details are definately needed.