Tarp for storage: Light or Dark color?

[RhythmDoctor]

I hope everyone in the US had a great Thanksgiving!

I've dropped the mast on my boat, and after completing some maintenance I plan to cover the whole boat with a tarp, using the mast as a tent support. I've heard conflicting comments about what tarp to choose. Some say white is better because dark color will heat up the boat too much and cause humidity problems, while others have told me that dark color is better because it blocks more of the sun's UV, prolonging the life of the gelcoat. Or I could buy a silver/black combination and put the silver color up to reflect heat but still block virtually all the UV.

I'm interested in hearing the debate from all of you here. What do you suggest? Any other considerations? (FYI, I have a couple of DampRid canisters inside to help trap any humidity that accumulates.)

Here are my two leading candidates - pretty wide difference in price due to different mill thicknesses and other features:

White tarp

Black/silver tarp

[dub420sailor]

I am interested as to what people say to this. I currently have a cover on my boat but a tarp over that to keep the water off since the cover keeps pooling up (set up in a tent configuration over the mast). So far reflective has done well for me but then again I also have the cover on underneath...

[bljones]

Rather than colour, go with the thickest tarp you can find, and if you can, see how the grommets are fastened. If the grommets tear out the tarp will be useless. The second tarp you linked, RD, looks like it is a tarp that will do you well for at least a couple of seasons.

[sailingdog]

Color is a consideration, and darker colors will tend to cause the boat to heat up and act as a moisture pump. As the boat heats up during the day, the air inside, being warmer can hold more moisture. Then, as the boat cools off at night, the moisture condenses out inside the boat. In very, very cold climes, this isn't as much of a problem, since there isn't as much available moisture in the air, but you're not that far north, so I'd recommend going with the heaviest, thickest, light-colored tarp you can get. :-)

[downeast450]

I am a proponent of white covers. Heavy duty, I buy online. I use white because it lets more light through. I work on my boat when it is covered, both inside and on deck. Having a HD white tarp allows me to see everything on deck very well. I use two tarps. The main tarp is white and I cover the cockpit area with a clear tarp for even more light transmission. With the clear tarp over the cockpit I get all the light I need inside the boat when I am aboard working. I shock cord every grommet. Use no hard, un shocked, ties anywhere. Your tarp will last for years. I have "discovered" a little plastic hook that lobster men use for their trap doors that will cinch down on a piece of 1/4 ' shock cord and has a hook large enough to attach to my aluminum toe rail openings. This little hook is perfect for this job. It makes adjusting the length of the individual cords a simple matter of pulling the shock cord into the "cinch slot" at what ever length you want. Most of my shock cords are lengths less than 1 foot long, along the sides of the boat with long ones at the bow and stern that run under the hull and connect the sides of the tarp sharing the load. I cut some PVC pipe "Ts" so I can slip them over the tops of the stanchions and I tape a piece of foam pipe insulation over them. If you do need to repair a torn grommet or reinforce one you are concerned about I find that Gorilla Tape makes a very strong repair with a 1/2"grommet tool to provide a new grommet.

Good luck

Down

[rikhall]

You may also want to check with the "rules" for where you store it. We are negotiating with the city for a new lease on our yacht club property (we lease it). The new preliminary lease from the city requires all tarps to be white by 2013. Seems some city planner thinks white looks better. Hey - it is their property.

A few hints from one who has "tarped" now for 16 years:

1. no flapping! it must be secure if you want it to last. A few 100 foot packages of 3/8 line snugged over after the tarp is all secured can greatly increase the life of the tarp
   
2. when in doubt - pad the "frame" I got a bunch of scrap carpet from a huge carpet supply place and padded any place where the tarp was tight against the frame. I held the padding in place with plastic ties.
   
3. check it often - only takes one or two loose point to cause flapping (see #1) and tearing.

As an aside - when I go down to check the boat, I undo the aft end and climb aboard. A light tarp makes it much brighter inside and I can sit and remember the past summer's sailing.

Rik

[Minnewaska]

Seems the professional custom tarps are light color.

[cormeum]

For a glass hull it may not be such a big deal, for wood, light only to avoid thermal cycling. Dog's comment about moisture makes sense if there's a source of additional moisture for the air to absorb. if the boat is dry, I wouldn't think it'd make a difference.

[TintedChrome]

I have the silver tarp covering my boat right now. So far so good.. boat next to mine has a thin blue one similar to the white one you linked (guesstimating it's the 6-7 mil) that was just put on when I put mine on. When I went back a week and a half later to tighten out the inevitable stretch in the tie-down ropes, mine was fine while his had shredded itself to pieces despite being tied down in a similar fashion to what rikhal mentions.

[RhythmDoctor]

So I might go with an all-silver one instead:

16' x 30' Heavy-Duty Silver Tarp, 6 oz. / 14 x 14 Weave - Tarp and Cover Superstore

One question about size. My boat is 25' hull length, but a little longer due to transom-mounted rudder and bow pulpit overhang. The mast is about 28', so it extends a little over the bow and transom. Beam is 8'6". So I was assuming a 15'x30' tarp would be about right. Is there any problem with a couple feet of excess tarp off the bow or stern, or does that become a "flag" to flap in the wind and lead to tearing? If so, what size would you recommend for my dimensions of boat?