How to Fill in Gap Between Balcony and Gutter

Warren in Vancouver, Washington is having an issue with a deck. Tell us what’s going on.

WARREN: Hi. I have a second-floor deck that’s got safety-deck coating on it, so it’s waterproof?

TOM: OK.

WARREN: And so it slopes out away from the house to a gutter, OK?

TOM: OK, good.

WARREN: And of course, the gutter has – it’s got, essentially, flashing in it, laps up onto the deck. So when it was constructed, there’s a little lip right there at the gutter. So water doesn’t completely drain into the gutter and then whenever water evaporates, I’ve got all this debris and dirt that was in the water that has now stuck to this granulated decking.

And I know you’ve talked about self-leveling stuff but I want to fill in that little gap – maybe 3/16-of-an-inch – but I want to keep a slope on it and I don’t know what to use.

TOM: So, what you’re saying is that the gutter is actually above the edge of the deck or it’s slightly below but there’s some sort of a gap in between?

WARREN: It’s below but the flashing has got an edge that is on the deck.

TOM: Right.

WARREN: And when it was – and when all this fibrated emulsion was put on, that actually created a lip.

LESLIE: So unless that rain is really moving, it’s going to sit there.

TOM: Yeah, it hits the edge of the flashing and stays.

WARREN: That’s right. A little bit and – but then it …

TOM: Is there any way to reflash it so – because it sounds like the flashing is put in exactly the wrong place. I mean typically you would not put flashing on top of the surface you’re trying to flash. You’d put it underneath so that the water rolls from the deck to the flashing to the gutter.

WARREN: Oh. No, the flashing was attached to the plywood decking and then this fibrated emulsion was painted over it.

TOM: But it still sort of raises up a little bit at the end.

WARREN: Yeah, yeah. It’s got to go over this edge at the end, yeah.

TOM: Well, the thing is anything that you do to build that up right now is going to require you to take that emulsion down or put more on top of it, because you’ve got a coating there.

WARREN: I’ve got a 5-gallon bucket of the stuff.

TOM: Oh, you do. So it’s not a problem.

WARREN: Yeah. Yeah, yeah, I could give – you probably know what I’m talking about, the product.

LESLIE: Yeah.

WARREN: OK. So, yeah, that’s not a problem. I just – before I painted it down again, I wanted to – and it’s a granulated thing so you don’t slip on it. But I wanted to fill that in somehow before painting it over.

TOM: So, I think what I would probably use in this situation would be like an epoxy patching compound, similar to what we would use on a concrete cracked surface or the kind of – there’s also – it’s also …

LESLIE: Like a subfloor resurfacer.

TOM: Well, you know what? It’s also used to restore rotted wood and – because I want something that’s going to really adhere well to the substrate. So I think that if you used an epoxy compound, that that would probably be the best because it will stick really well to that existing roof deck and not delaminate.

LESLIE: Does he need to do anything with the finish on top, that anti-slip surface? Because that may eventually break down over time and would that cause this new, leveled surface to sort of delaminate?

TOM: No. That’s why I said yeah, he does have to take that down first, because you can’t put it on top of it. So you have to basically sand that down, get rid of that, build it up with the patching compound: the epoxy-based products. And then once the slope is just letter-perfect, then you put another coat of the emulsifier on top of that.

WARREN: OK. So I’ve got – it’s 30 feet long and then I’ve got – I may have to taper it back.

TOM: Right. Exactly. Yeah, you’re going to feather it up and essentially use a very wide trowel, like a 10-inch – almost like a 10-inch drywall knife.

WARREN: Yeah, no problem. I’ve got those.

TOM: OK?

WARREN: Oh. So an epoxy patching compound.

TOM: Yep. Yeah. There’s a company called Abatron that has a wide variety of these products. You might want to give them a call and find out the best one, because they have different formulations. But that’s their website: A-b-a-t-r-o-n.com.

WARREN: OK. I’ve got that. Yeah, I think I looked at that for something-crete: Abotrete or crete?

LESLIE: Abocrete, yeah.

TOM: Yeah. That’s one of the products, as well.

WARREN: OK. But this – the epoxy won’t get me into the self-leveling dilemma. I’ll be able to use this instead.

TOM: I think so.

WARREN: Oh, OK. Well, that’s what I’m looking for.

TOM: Alright, Warren.

WARREN: And then I just build it up a little at a time and then put down this – put my paint back down again?

TOM: That’s right.

WARREN: OK.

TOM: Alright. Does that answer all your questions, Warren?

WARREN: Yeah. I’ll just have to find enough dry days to do it.