Flashing at Butt Joints on Lap siding?
I’m a remodelling contractor in Washington State, and enjoy the unique education I receive every day in how NOT to build homes to last 100 years. This is a topic I could go on at length about, but I have a specific question I’d like to start with. Am I a freak for liking to back up butt joints on horizontal lap siding with a scrap of building felt or, better, with some 4″ peel ‘n’ seal tape. It seems to me that no matter how pretty a caulk joint you lay inbetween your Hardi-planks, it will go T.U. long before the homeowner notices. When using real wood clapboards I prefer no caulk at all; just a nice miter cut and some tape behind every butt leading water onto the face of the course below it. Am I the only one doing this, and am I wasting my time?
Replies
I'm not saying you're wasting your time, but on all the 100 year old houses I've worked on I've never seen flashing behind joints. Your building paper is keeping the water off of the framing and if the building is reasonably maintained (caulked and painted as needed) then there shouldn't be a whole lot of water going into the joints anyway. If you're cutting into existing siding and trying to splice in patches, that's different because you're probably hitting the felt with the japanese saw as you cut into the existing. Anyway, if you've got something thin enough to flash behind siding without causing it to puff out then I don't see why not.
i always cut a 1" x 6" pc of metal flashing and bend a small lip about a 1/8-1/4 wide to hook on the siding and hold it in place till the pc over it holds it in place. works great, i don't know as it's needed but i sure feel better about it. i can make 50 or so on my brake in about 10 mins for a cost of maybe 3.00. so it's great insurance. larry
I don't think you are wasting your time. The last siding job I did (redwood clapboard) I not only used 30# felt strips on the joints, but I made a point to paint the fresh cut before nailing. I do use caulk in the joint, however, and I notice that the joints are still tight a few years later.
J Painter
I do it and I prime cut ends before intalling. I'm in Washington too.
Smile. It could be worse. You could be me working for you.
Me too. Metal flashing or peel & stick. Prime raw edges. Matters less with a rain screen design.