What do you call small roofs sticking out of the side of the home such as these with the metal copper penny roof covering? Sometimes I see these types of smaller roofs sticking out of the wall with gable and shed styles. Seems like there’s a more accurate description of their architectural style that I need to learn. I called these ones out for not having kickout diverter flashings.
No, they do not have or require ventilation. Unlike a gable or hip-type structure, they will not have an accessible attic space. Insulation is usually EPS or Poly-iso foam board.
That’s why I asked about it. I’m not entirely certain what the standards are for venting a roof with an EPDM roof covering. It did feel like there was insulation underneath the EPDM roof covering.
What other pictures would help you to answer my question?
This roof had bathroom vents, a flue vent, two gutters, and four plumbing vent stacks.
Is this the standard that would apply to this roof (2018 IRC)? It appears that the ceilings are applied directly to the underside of the rafters:
R806.1 Ventilation Required. Enclosed attic and enclosed rafter spaces formed where ceilings are applied directly to the underside of the roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow. Ventilation openings shall have a least dimension of 1/16 inch minimum and ¼ inch maximum. Ventilation openings having a least dimension larger than ¼ inch shall be provided with corrosion-resistant wire cloth screening, hardware cloth, perforated vinyl or similar material with openings having a least dimension of 1/16 inch minimum and ¼ inch maximum. Openings in roof framing members shall conform to the requirements of Section R802.7. Required ventilation openings shall open directly to the outside air and shall be protected to prevent the entry of birds, rodents, snakes and other similar creatures.
R806.2 Minimum Vent Area. The minimum net free ventilating area shall be 1/150 of the area of the vented space. Exception: The minimum net free ventilating area shall be 1/300 of the vented space provided both of the following conditions are met:
Does this house have an attic? Looking at the pictures, I would say it does not have an attic other than what is made by most likely truss framing or however it was framed. This is not unlike a cathedral ceiling in the way it should be insulated. The difference is that with a cathedral ceiling design, you can have soffit venting, but with no soffits on a flat roof with parapet walls, you do not have that. I have yet to see a roof vent on any membrane roof covering.
All you can do, is report on what you see. You cannot access the area above the interior ceiling so you have no idea of how it is insulated or finished off. Flat roofs in general or in this case a low sloped roof because no roof is really flat generally have no visible ventilation points like you would see on a shingled roof.
For me, this roof would not raise any red flags of a problem unless I found something inside, in which case I would use my moisture meters and an IR camera to help me figure out what is going on.
I guess since I have seen so many roofs like this, mostly in commercial settings but also in residential construction, I understand them, and I’m comfortable with them.
Ventilation or no is not decided based on the roof covering material. It’s decided based on the insulation material. If insulation is closed cell foam, no ventilation is needed. Moisture does not move through closed cell foam.
If the insulation is fiberglass batts or a similar product, ventilation is necessary. Again, venting requirement is determined by the insulation material. I have inspected EPDM covered roofs with fiberglass insulation, so don’t assume the insulation material or venting requirement based on the roof covering.
When insulation is inaccessible, I use an IR imager to make a guess as to what the insulation material is. Foam 4 x 8 sheet insulation, one can often see evidence of nails in the insulation field. Fiberglass will have no evidence of nails in the field and will usually show rafters/purlins in the image. Many times, identifying insulation type using IR is not conclusive, and both insulation type and ventilation requirement need to be disclaimed.
Seeing this statement from you about “engineered roof rafters”, I’d be careful assuming the insulation is closed cell foam. Maybe it’s closed cell foam sprayed to the underside of the roof deck, or not. That type of roof can just as well be insulated with fiberglass. You don’t know. For exhaust venting, EPDM flat or low pitch roofs that I’ve seen utilize turbine vents or aluminum or galvanized pipe type vents with a rain cap. Intake venting has been in other areas, the parapet wall IIRC.
I’ve decided to say that the ventilation for this roof was not inspected.
Here’s my comment:
[[Not Inspected]]The inspector was unable to determine what type of insulation was used in the low-slope roof configuration with an EPDM roof covering. Accordingly, the inspector was unable to determine the exact ventilation requirements for this roof. Since the inspector was unable to access the interior roof components as well, the ventilation for this roof was not inspected. As such, the inspector disclaims any defects that may exist with the ventilation configuration of this roof.
Not to go off thread but was the EPDM in good condition?
I do not see any slope at the curbs. The roof surfaces appear flat. Flat roofs, despite their name, are not completely flat. A low roof pitch, also known as low slope, is generally defined as under 3:12.
I would refer to the roofs or architectural designs the front of the home, the fenestrations as; Arched Copper covered front door and garage door awning roofs.
Generally, flat roofs (technically low slope) with this type of rolled single-ply covering generally do not require ventilation. The roof you have pictured appears to be insulated at the exterior by using insulated panels commonly known as ISO board. And in conjunction with a thermal/vapor barrier, this design protects the roof decking/sheathing and eliminates the need for venting.
Of course, you cannot see these layers. Therefore, you are limited to observing the condition of the visible components and their performance.
It may have had one roof vent, but I was not sure.
I sent off the report last night.
My comment stated that it was not inspected. In this thread alone, I’ve had people tell me that it DOES NOT need ventilation, that it DOES need ventilation, and that the ventilation cannot be inspected due to obstructions. That’s three totally different responses that could not all be included in the report.
How do you know that this roof has ISO board insulated panels? I know that there was some type of insulation underneath the EPDM because I could feel it squishing underneath my feet. I suppose that you could also draw that inference from the fastening pattern that’s visible on the EPDM roof covering.
I did read through a lot of that manual where you got the screenshot from.
The roof contour to the drain is a primary indicator. The ISO board will be stacked and contoured to control water flow. And the squishy feeling may be another indicator. ISO board are thick foam panels. I know immediately when I step on these roofs. Also, the era built (2006). What I describe is typical modern construction.
Now, when are these roofs ventilated?
When the insulation is not as I described, you may find this membrane rolled directly over the roof decking with no insulation panels. (Common with old buildings). In this case, you will find different forms of roof ventilation. Here is an example of an old low-slope roof that is ventilated. Edit. It likely has a low plenum or crawl between the ceiling and the decking. Insulation may be present there.
It seems like that squishy feeling under my feet can only be one product that’s currently on the market. To me this leaves out little room for speculation about it’s existence.
Is it speculative to say that the space between the roof and the ceiling joists does not have ventilation or does not require ventilation? It’s pretty clear that there wasn’t room for much more than rafters between the ceiling that the skylights.
