Deck painting over winter

[AiniA]

Just bought a new to me 43 year old Nonsuch and want to do a full deck job on it. There is only one smallish delam area, say 1 sq ft but lots of areas that are damp but not delay. Boat will be hauled in a couple of weeks and will be shrink-wrapped. By early spring I should be ready to paint the deck, I think with Alexseal. At that time of year it tends to be warmish under the cover, especially if it its sunny, but can be quite cool at night. I appreciate that this will slow the chemical process so it will take longer to set-up. I can live with that but is that the only problem? Boat is in the Toronto area.

[Oeanda]

We cocooned our boat this fall for similar reasons, but plan to heat the bubble at times while we work on it. In our rainy climate it’s such a treat having a dry boat that we have no end of things to work on under there. Propane heaters can heat up the bubble very nicely, though might not play well with paint fumes...

[JPA Cate]

Ainia,

It will take someone with more expertise than me, but I would think that shrink wrapping the boat would help the moisture that is in the deck spread, and then when it freezes, the water will expand and increase the areas of de-lamination. Therefore, I would suggest treating the whole deck and get the damp out of it in the next two weeks. Pretty sure that's not what anyone would want to hear, so a pro opinion would be better than my suggestion, but it would be really awful to approach it the way suggested in the first post and come back to a much worse problem.

Maybe boatpoker will have some input?

Ann

[tkeithlu]

Not a problem we face down here in the sunny south, but shrink wrapping a damp boat sounds like a making a wonderful ecosystem for mold and mildew. Any chance of including a dehumidifier to extract water under the wrap?

[steffan]

To the OP - if you will be keeping the boat for at least a few years in a climate requiring winterization, I would invest in a custom reusable winter cover. We did that last year and figured the break-even was 3-4 years at pre-covid shrink wrap rates. In our market the shrink wrapping price is up 50% since then. The cover allows better access and breathes a lot better. Certainly too late for this year, but something to consider for next year maybe.

[Oeanda]

FWIW. We made our cocoon out of pvc conduit pipe, bent to form a series of semicircles. Fastened to the outside the rails. The pvc is surprisingly strong and the dome shape is roomy and doesn’t pool water or snow.

We didn’t use shrinkwrap though we probably would’ve if it was available here. Regardless, we left air openings at both of the bow and stern. There’s no rain getting in the ends now, but we can always close them up if we want to.

For ventilation we have regular desk fans as well as a large 500 CFM vent fan if we need it. Run a shop vac while sanding, etc. Also electric heaters, propane heaters, and a dehumidifier down below. The whole affair could be covered further for insulation value.

Toronto climate is colder than here but my point is, there are a lot of possible options. I don’t see any reason your boat needs to stay wet inside when covered. The end result in our case is- for a couple days work we ended up with a nice cosy working environment where we are free to putter away on the boat all winter while the wind and rain blasts outside.

[AiniA]

It is quite dry inside the shrink-wrap. My concern in posting was about any ill effect of putting paint on say around noon when it is toasty on deck, but ten hours later it could be below freezing point. Oeanda, I read the Alexseal application guide and they recommend against propane heaters because of contaminants given off.

[Oeanda]

I’d look around for a good rep from the paint company to help take you through the process.