Metal flashing question
Is it recommended to put metal flashing over a sloped cedar drip cap? If so are these mass produced or do you have to make your own?
my other flashing question is where in the wall system does that flashing (if recommended) and the flashing that will cover the 5/4 water table trim board/belly band go?
My systen is is as follows:
sheathing
wrb
furring strips
trim/siding
Is there a rule of thumb for where all horizontal metal flashing goes? I’ve just seen so many different ways to do it. Some people fasten their flashing to the sheathing, others to tenfurring strips… maybe it just depends what you are flashing – which is why I asked about those two specific places.
thanks for the help.
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Replies
Kevin,
The rule of thumb for flashing when you have a rain-screen cavity is:
- Flashing goes back to the sheathing (and is lapped by the WRB) at any opening where you want to direct the water to the exterior. So Windows, doors, lights, vent-terminations, etc.
- At horizontal changes in cladding, trim, etc, the flashing is m0unted on the furring so that the continuity of the cavity from foundation to roof is maintained.
To answer your two questions:
- You can look at the drip-cap as wood flashing (thats what they traditionally were), or as decorative and needing a metal flashing above. That's entirely a judgement call - although our code would preclude using it as flashing most locations - and as per above, where it is located determines what you mount it to.
- The belly-band is mounted to the furring and needs a cap flashing above. Again you have a choice for what happens below. You can rabbit out the bottom to provide a lap for the siding, or use the same flashing as you used on top.
Malcolm, thanks for that information, very helpful.
A follow up for you... what are your thoughts on me making my own drip cap and sill out of "premium grade" s4s kiln dried 2x4's (what's at my home depot or lumberyard), instead of buying the stuff finger jointed? I could save a lot of money making my own just don't know about the quality/durability of those pieces made out of 2x4's instead of buying the finger jointed.
Thanks again.
Kevin,
For sure, make your own. The durability of the cap will rely on the finish more than the wood.
The 2x4s you want to use are what wood species? SPF will not last no matter how careful you are with flashing/finish (at least where I live).
Joel, Cedar, western red KD. clear.
Ok guys, seal the flashing overlaps!!! Water runs uphill and sideways, believe it!! Unless you have a 30' long metal brake you will have several pieces in a row.