Even a modest cover will help enormously, and it doesn't need to cover all of the boat.

 

Here's a couple of photos of my setup taken last month. The frame and canvas cover were made by Fairclough 5 years ago. The ridge is fairly high, helping to shed snow (most of the time), and allowing storage of the dodger in place (although the Bimini comes off--frames and all). The 1 x 3" furring strips are secured with 1/2" fiberglas strapping tape and specifically offload the lifelines.

The cover is fitted and had shrunk to a tight fit during the first season (Fairclough knows how to cut these covers!) The tie lines under the boat are doubled, which helps to gather the canvas and maintain a tight fit to keep the flapping down.

Some might argue it is not necessary to cover down to the waterline, but check out the gloss on the hull, which is the original 28-yr old gelcoat. You are paying for the extra material of course and the cover is rather heavy, which is why we had the back section split into 2 parts this fall (note the second zipper near the aft vent.)

The cost for the frame and cover compares to the cost of 5 years of shrink wrap, so we are at the break even point and this cover will go another 15 years, as demonstrated by the existing 20 yr old fitted canvas cover (tired, but still serviceable) on our 28-yr old ********.

I prefer a fitted cotton canvas cover, having had a sunbrella cover for the previous 17 or so years for the sailboat. The cotton fit is better,--almost like shrink wrap, doesn't wear off the zinc on the metal frame members, and it outlasts polyester canvas. Many years ago, I used tarps for my boats, but was never able to get a satisfactory tight, flap-free fit.


The last photo shows another winter (actually year-round) cover in the background at Mystic Seaport. That cover protects the Mayflower II and shipyard workers during a multiyear restoration in preparation for the 400th anniversary of the Plymouth Rock landing. BTW, that structure is known locally as "the mailbox".

 

I am about to start putting together the frame of my 'new to me' winter cover on my 'new to me' C36MKII. It is similar to Fallards and has the frame of what appears to be a full size T-Rex. Wish me luck :O

My last bot had a cover was the type that tented the boom and went to the toe rail. I could put it on in less than two hours by myself.

Either way, they are worth the investment.

 

Throwing my 0.02c in as I've always covered my boats, especially after witnessing uncovered boats up here. I will also echo the "it probably depends on where you are and what your definition of winter is". The winters here in Northern Ontario start with fall (Sept. usually) rains that pour and pour. We then freeze up, usually first week of November has some -20c nights, October is good for snow as well before that.

Last week it was -32c without the windchill (for reference).

A friend of mine has a G23, he bought it for 800$ and tends to treat it that way. One fall I was wandering by his boat and he did not have the cockpit covered (this was mid-november). The fall rain\snow\rain\snow\freeze had filled his entire cockpit up to the lazarette lids with a block of ice. To not exaggerate it was at least the size of an engine block from a pickup truck. The trailer it was on blew 1 tire from the extra weight and the axle was looking scary (bending). Now maybe if he was there every day to visit the boat he would have shovelled out the snow\slush slurry that was forming and compressing into ice. My boat was 10ft from his with a 60$ (CND funds) tarp on it leaving it bone dry and not a snowflake ontop.

The weight of snow\water\ice is significant to say the least. I tarp my boats the second they are out of the water because not only do I stop snow from piling up but I also stop the soaking fall rains from pouring into every nook and cranny. Tarping it in the fall let's the boat dry out a bit before the big freeze happens, and I find it makes a big difference in crazing, leaks, and dank smells\mould.

Here's how we tarped my Mirage 33 this fall, it took 100$ of tarps and a wood frame that came with it when we bought her. The biggest downside is the time effort it takes (a day) to do the tarping. I was quoted about 3500$ Canadian to have a custom cover made with an aluminium frame. I may go that route if for no other reason than the custom cover will go up faster and need less "tweaking". The silver tarps are tough but with several 30, 40, and 50kt storms occurring each winter I consider them disposable because they almost always find a spot to chafe through leaving small tears.

Pic attached. For reference there is a small opening at the transom to let airflow in, and where the tarp goes down the hull below the waterline it is tied to the cradle so the boat can also breathe vertically along the hull. We remove all canvas and sails, and all pillows\linens and put them into indoor storage.

EDIT: Don't ask me why the tarped pic is upside down. The pic is rightside up on my desktop, just like the frame pic.

 

I always thought a slow snow melt would allow water to saturate anywhere a void (small cracks)existed.

If finances allowed I would cover with a

1) Canvas Cover
2) Shrink Wrap
3) Tarps - (See Below for current financial status)

 

I use mine in Southern California because I painted the deck and I really don't want to have to do it again for a few more years. UV protection is really the only reason to do it. that, and it came with the boat. I keep a light on below to prevent mildew.