| Hi, I'm in Toronto Canada. I've just been appointed property manager
| for a small church (the fact that I know absolutely nothing about
| building maintenance didn't seem to faze the congregation). The
| building dates back to 1889, and it badly needs a new roof. I've
| received quotes from four roofers. Of the two I'm considering, one
| recommends a ridge vent while the other recommends no vent at all.
| There is a flat ceiling, so there is obviously "attic" space between
| the ceiling and the roof ridge. There has never been any venting, so
| the one roofer said you've gotten along without it so far, you might
| introduce problems by venting it now. He didn't say what problems there
| might be. The other said a vent would help preserve the roof longer.
| Which one is giving the better advice? Any thoughts. Many thanks in
| advance for your help.
Dating back to 1889 the roof would most likely have been cedar shingles over a roof strata wherein the boards/planks were not butted against each other except at the ends. The result would be a roof that is naturally vented via the spaces between the planks.
New roofs that use ply for the covering also do not include spacing between the sheets. This is why venting is required on them.
If the roof is not sheeted and you are putting up cedar, you most likely will have no need for venting.
If the roof is sheeted or you are putting up asphalt shingles, add venting.
Somewhere in the church there should be a trap door for accessing the attic. Have a look to see what you really have.