Attaching Posts to an EPDM covered roof


#1

I need to attach a few 4X4 wood posts to an existing roof deck with an EPDM membrane bonded directly to an OSB layer. The underlying roof deck combined with the OSB is substantial and lag-screwing some sort of post anchor plates to it would be plenty strong . . . but it would need to be water tight . . .

  1. Is there a standard type of anchor plate or device that works well? Brand or description?

  2. If I use a standard metal post base, can I get by with sealing it to the roof with some type of rubber caulk, or would I need to flash around each post with rubber? If so, is there a type of post base that is easy to flash?

  3. Are there any tricks that work especially well, like building up a flashed-in raised block under each post to keep water away from the attachment point?

Thanks in advance!

Al


#2

al
go to your local roofing supply store and ask about chem-curbs. they will seal your posts and are easy enough for the d i yer to install. or just google it.


#3

Thanks roofboss!

I found Chem Curb on the web. That looks like it will do the job, and I think I can get the material through my local Fastenal. It looks simple. (I think I can even do a neater installation job than the guy on their demonstration video.)

I’m open to other suggestions too . . .

Peace,

Al


#4

although I am not sure of the purpose of your railings, I do know that for a deck railing application, new codes require 500# test ratings for the railings.
Hope this helps


#5

[quote=“baycompany”]although I am not sure of the purpose of your railings, I do know that for a deck railing application, new codes require 500# test ratings for the railings.
Hope this helps[/quote]

Thanks! Yes, it’s basically a deck railing on a seldom used entryway roof. I plan to construct the top rail in one piece and fasten it to the building on both ends, so lateral strength shouldn’t be a big problem. I’ll do some calc’s just to be sure.