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Flashing around 4x4 posts

We have a flat roof balcony over our porch. I have had a lot of difficulty figuring out how to flash the 4x4 posts that make up our uprights for the railing. Not sure if anyone knows of a premade flashing I could just slide over the post and secure under our rubber roofing membrane???

Re: Flashing around 4x4 posts

Are your posts metal or wood? how are they attached at the bottom?

By the size 4x4, I assume that they are wood.

Search on google and you might find solutions, OR, you can seal the area where the rubber membrane meets the post.

Re: Flashing around 4x4 posts

this is a extremely difficult thing to flash, wood will continously expand and contract which can allow water in.

a better way to do this type of patio is to let the deck system float on the roof and lock the post into the patio framing and not have it directly into the roof, there should be no penetrations in any flat roof unless its for a scupper drain

Re: Flashing around 4x4 posts

Yes, the posts are wood. They are connected directly to the joists. I now need to go back in and replace some wood as it has leaked around these posts and rotted out some of the flooring underneath the rubber. I understand that sealing this will be difficult, that is why I was hoping to find some kind of pre-manufactured flashing that could slide over the 4x4 posts that I could secure the rubber roofing directly to. Short of this, I will need to completely rebuild the structure (and I am not able to do that right now).

Re: Flashing around 4x4 posts

Grace makes an very nice Ice and water dam that is pretty much very sticky sheet rubber. There is also the same type of material available in rolls in the roofing sections of the big box stores. You want the very flexible stuff.

You'll be making your own flashing, going up higher than the snow level.

As stated before, this isn't the optimal way to attach the decking to the main structure.

Re: Flashing around 4x4 posts

We always box in these kinds of posts; yes, flash to the 4x4, but then wrap the entire thing with a box of suitable exterior wood, so all of the flashing is hidden, and weather-tightness is ensured. The 4x4 is just the base for a wrap, which can be as much or as little detailed as you want.

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