I’m in the process of finalizing a number of details on an addition and wanted to ask if anyone out there had a flashing detail on mating a masonry chimney to a sidewall, particularly helpful if the masonry is tapered. Chimney is CMU with full thickness natural stone veneer. Siding will be WRC shingles on Slicker with Henry Blueskin over plywood sheathing. This chimney sizing/shape is inspired by a few Gustav Stickley designs. Thanks.
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For your masonry chimney to siding hookup, I'd suggest a kick-ass cricket detail to deal with that tapered chimney. Make sure it's weather-tight with some killer flashing – maybe go for a custom one considering the unique chimney shape. Also, seal the deal with some quality caulk and you should be good to go. Love the Stickley-inspired vibe, by the way. Keep it rustic and cool! Cheers!
How did you detail the masonry (block) flashing to the rough in (sheathing)?
Pictures would be a big help.
Well, the details are sketchy, hence my question. The mason gave my engineer the basics--we'll set each course of 8" CMU in about 3/4" starting around the 9' high mark. That will give me the taper from around 9.5' wide at the base to around 5.5' at the top. The veneer is full thickness natural stone, so will handle the taper as well. The flashing that bridges the stone to the sheathing/siding is really my question.
You'll want to use a flexible flashing material like lead or copper to accommodate the tapered chimney. Ensure it extends up the chimney sides and onto the adjacent wall. Use step flashing to integrate with the shingles, and counter-flash over the step flashing with the Blueskin membrane.
The key is to create a watertight seal that allows for movement between the chimney and the siding. Gustav Stickley's designs often emphasize craftsmanship, so attention to detail here will not only protect your home but also honor his aesthetic.
For flashing a masonry chimney to siding, especially if the chimney's tapered, you'll want to ensure a tight seal to prevent leaks. Start with a base flashing that extends up the chimney side, then counter-flash it with the stone veneer. Use flexible flashing to accommodate any shape variations. Make sure it overlaps the siding properly for a watertight fit.