1.5 story house
3 sections
all same roof slopes, center section is 2 feet taller than the outboard sections,
Chimney bisects two of the roofs on the backside only (not at the ridge) midway down the back slope.
2+ feet bisects the center section and about 4″ bisects the lower outboard section.
Chase is framed around SS flue boxed with ply and had siding applied directly over.
Big section on the higher roof was flashed approximately 1′ up the chase and that 1′ tall x 2′ wide flashing nailed off maybe 3 nails
lower 4″ section flashed maybe 8″ up the chase but nowhere near as high as the upper flashing.
step flashing down the sides as should be
siding put directly over this and raw ply
leaked
I torn off all the siding and proceeded to caulk all the flashing tops and all the gaps in the ply. Water had to be getting behind the siding and then either behind the flashing or in through cracks in the ply. I then applied tar paper bottom to top around the whole chase.
Still don’t like the fact that the water rolling down the roof hits that vertical wall at both the 2′ section and the 4″ section. I don’t think there would be enough volume for the water the climb above the 1′ tall flashing but I still don’t like it.
The issue is cricket or not and what to do about the upper cricket (2′ section) if I do put crickets in. Commonly they would split the water 50/50 down a valley on each side of the chimney, not? but in my case, splitting it 50/50 is going to dump half the water down into the 4″ lower section which doesn’t seem like a great idea. Any thoughts on building the upper cricket (2′ section) so that it is basically 1/2 of a normal cricket such that it diverts all the water around the chimeny to the inside center section of the roof?
Its not likely visible from ground level and the outboard side (what would essentially be a wall) would be finished similar to the 2′ gable end that shows above the lower roof section. It would be pushing all the water around the one side of the chase towards a dormer sidewall but there probably 4′ clearance there.
Replies
You don't say what the slope is or if you did, I missed it. If the roof is 8/12 or less, I'd do a "half cricket", but the slope does not need to be too extreme. Just enough to divert the water (1/12 maybe) to the side you want it to go to. I'd then close the high end off with a 1"-2" lip. Steeper than 8/12 and I'd do the same, but make the cricket slope steeper and the lip taller.
copper p0rn
Sorry,
8/12
Thanks for the suggestion on the lip. Hadn't thought of that.
You don't mention what you are doing with roofing after you do the crickets.
With all those different angles down slope and up I would get some ice and water shield.
Will Rogers
We're not getting crazy here. This is just a rain diverter for what is already a waterproofed solution. What they originally did would have techinically been fine had the lower flashing come up to the level of the upper flashing AND they had put tyvek on the chase like the did the rest of the house. But they got lazy.
sounds like you have the crickets well in hand. "There are three kinds of men: The one that learns by reading, the few who learn by observation and the rest of them have to pee on the electric fence for themselves."Will Rogers