Waterproofing 2nd Floor Balcony with Living Space Below
I am a homeowner, not a builder, and I have no silly plans on this being a DIY project…Just looking to make sure I find the right solution and trying to get as much expert advice as possible to solve the problem and let the experts handle this.
As you can see from the picture I have had water damage in my soffits, window rotting, steel lintel rust, etc. I have been putting off the issue because of a large scale remodel of the kitchen that has been in the works for a few years. Now that we are renovating we dug into the problem a little deeper and realized the root cause.
When reviewing what was done on the second floor balcony (living space below) it appears that the original builder used a waterproof membrane to keep the water out of the interior of the home. This was successful as we have had no water penetration in the interior. However, he did a poor job of funneling the water away from the structure. As you can see he wrapped the waterproof membrane between the exterior masonry and the soffit, resulting in the water just running down off the membrane, into/behind the soffit, down the masonry wall, into the windows /structure below. There is a large roof overhang so the amount of water is not too great so that probably helped mask the problems for years and limit the amount of water, however, as you all know even a small amount of water over time creates an issue and that’s what I have.
I want to put all new windows and door wall system below in the kitchen area, but want to make sure I manage the water issue correctly first.
Any advice on the best method to waterproof this. As you can see from the picture, it almost looks like the soffit was an after thought as the builder just toenailed some 1×10’s onto the exterior of the home (this may also explain why the membrane is where it is…who knows?). The balcony above is just a womanized decking that is spaced to let the water through and the membrane is doing all the work. I would hate to tear up what I have as it is actually working to keep water out of the house, but would rather utilize it as a last line of defense and just go over the top of what is already there.
Any advice would be GREATLY appreciated. Thanks in advance!!!!
Replies
Hey there. I'm no expert, but I spent a lot of time researching before I just built my EPDM roof last month over a protected 3-season living space.
Do you know exactly what the "rubber membrane" is that is tucked behind the overhang framing? Knowing that may provide more information about options for extending that membrane. When you remove the rotting overhang, preserve as much of the membrane as possible, then maybe you can add an extension piece properly over top of the repaired overhang framing.
If, for example, the membrane is EPDM and you can get enough loose to have a little flap to lap to, maybe then just buy some EPDM and double-sided lap tape and sealant. Here's how you would do that with a firestone product: (https://www.youtube.com/watch?v=AD8jyqnPtY8) Obviously you would need to lap the old piece over top of the new piece. If that's not possible—don't be tempted to merely use a tape to bridge the two membranes. Proper lapping is the only way.
Also, make sure that the existing and new membranes are thoroughly cleaned. Rubber that's not too old and not showing any signs of dry-rot can be revitalized with a stiff scrubbing and it's possible to form an excellent bond.
Hope that helps.
I agree. From the looks of it, my guess is that it is EPDM. I believe most small flat roof work is done with EPDM, but you need to make sure that your repair like with like.
I would plan on a gutter on the reconstructed overhang with the membrane hanging in the gutter to insure all water is directed into the gutter. It will require a metal termination bar to hold down the exposed end of the membrane.
Many contractors including many who call themselves roofers haven't bothered to read the directions or think they can cut corners. This includes using the cleaner/primer for the roofing system. Gasoline is NOT a substitute.
Since the original membrane hasn't leaked it doesn't matter what it is. The fix is to have someone who understands flashing reflash the deck so that there is a clear path for the water to exit on top if any wall finishes, or, even better into a gutter. If you use a gutter even it will need to be flashed on the ends where it butts into the walls. Flashing does not mean caulk.