Leaking scuppers

We've got three scuppers on each side. They're the usual fiberglassed-in connection between the hull and the deck. The forward four are apparently in good shape, not obviously cracked. I presume that area of hull and deck are affixed together.

The aft scuppers are about as far aft as you could have them. The boat is an Europa-styled sedan so there's a generous back porch over a generous Lazarette. There is precious little tying the hull to the deck except the scuppers, the bulkhead under the aft end of the house, two glassed-in beams framed into the transom, and the surround of the transom door. The two scuppers are cracked around their inboard ends and the transom door sill is also cracked. These TTs were built with side and transom doors in various places (center, to port, to starboard, sometimes on one or both of the sides). I think that they cut 'em in where the dealer wanted them and they made up the jambs and sill later which would explain why my door's edges and its jambs all show the end grain of a wood member up under the caprail.

Ahh, but back to scuppers! I've spent quite a few hours in the Lazarette this spring (swim platform bracket mounting, genset exhaust redo, limber holes, shelving redo, etc.) and am disinclined to be there more! The scuppers definitely leak and they look cracked from above. I had thought of glassing/tabbing the deck to the hull in a few more places around the back porch but this is work for a young, supple (and low-ranking) workie. I had also thought of re-glassing/recreating the scupper while working from on deck. This weekend I had the thought of bandaging across the crack with, say, white EPDM or PVC roofing material. Expansion joints and scuppers in buildings are often done in similar ways; see pic.

Thoughts? Experiences? Suggestions?

Greetings,
Mr. DH. I think membrane roofing is quite a viable way to go. No experience but many years ago I considered re-roofing the main weather deck on our 1950 Chris Craft Commander with white membrane roofing so I have a bit of familiarity. I went with traditional canvas instead. I wonder, before you glue it down, whether judicious application of heat (heat gun) would help the membrane conform more closely to the tight corners? A sort of pre-form if you will...

I'm disappointed in the performance of these pvc roofs for lack of a better name. Geoflex is one brand, there are many. Differing rates of expansion and contraction eventually causes tears and seam failures.

I have it on about 40 buildings and long for the good old days of hot mopped composition. I think I deal with more roof leaks now than ever to be honest. As a temporary patch to get you by it'd be ok if you can source it. The heat gun isn't completely needed but in tight spots it'd help. Those roof scuppers in your picture are preformed from the factory.

Have you thought of replacing scuppers with drains?

I've had good luck with Glovit. Also had good luck with white Marine Tex. Also had good luck with fiberglass.

With all the good luck I've had you would think the damn things would stop leaking.

Craig, my (limited) knowledge about roofing and sealants, as an architect, is that care must be taken to give a place for the movement to occur. That's what bond breaker tape is all about behind sealants and that's what the little foam-filled bump is for on expansion joints. In this case, a little bump would be a dam, though. The good old days of hot mopped roofing were the days of coal tar bitumens; they never really got hard and they would soften and reseal around pitch pockets.

I've had 'hands on' experience with the long-discontinued Gates neoprene roofing and their uncured neoprene flashing materials. The stuff was supposed to cure after installation but it never cured and you could stick your finger through years-old flashing.

RTF, a hot air gun would be very useful for some elastomeric flashings, not necessarily for others. Might have to read the instructions(!).

As Louis Sullivan (long dead Chicago architect, mentor to F. Ll. Wright) used to say, "God is in the details".

More research required!

eternabond tape or even magic seal tape (as seen on tv) are flexible and grip like a pitbull. I might be tempted to try creep epoxy for the cracking.

The RV market has a white roof sealant that you roll on. It's fairly thick and is designed to fill crevices. We've used it quite affectivily on my parents trailer over the years.

We just had our Florida house roof redone with TPO material which is supposed to be the latest and greatest. Seams can be either welded or epoxied (ours are welded).
We were told it will last longer than we will. I hope they are correct.

I've got the same issue on our new to us 41' PT Europa. I'm planning on having a good fiberglass guy rework them and see if it holds. Is your gen. set in the lazarette? I'm wanting to get rid of my 8kw that's in the engine room and put a 5 kw with a sound shield
In the lazarette.

If you aren't concerned about the look, Eterna Bond tape might work. A friend had it on the roof of his RV in Arizona for years. Another avenue might be truck bed liner. There is a LineX dealer in Sarasota, Fla I think that does a lot of boats. He has a lot of photos on his web site.

PropN, our genset is in the ER. Since we carry a RIB on davits, I've been interested in moving weight forward, spare anchors and chain mostly. The dink was worth about an extra inch or more draft aft. Can't be good for fuel economy. Moving the pile of ironmongery on to the f'o'c'le, as far forward as I could reasonably get it, undid that same change in trim. Fascinating!

When you have your scuppers done, don't stop with simply repairing 'em. I'd add something serious, say a 12" length of 1/2" fiberglass sheet heavily tabbed to the hull and to the back porch deck adjacent to each scupper and another couple of pieces between the transom and the deck. The idea is to reduce the deflections/twisting of the as-built rather-loosely-attached hull and deck. I think it moves enough to have cracked the scuppers and the transom door sill. The two pairs of scuppers further forward are not cracked.

I'm with Downy, remove them and glass them over and install drains. Mmmmmm, bronze drains....or plastic, if you insist, but bronze is my choice. Did it with my GB32.