Arild writes...

My suggestion based on this and about a dozen years of working around
marinas
in Southern Ontario is to have shrink wrap or equivalent tarping with frames
done professionally.
Even without wood to protect; there is enough potential for damage when the
boat is located in any climate where there is at least a chance of freezing
for
a week or more.

Every spring the yards get a lot of repair work on boats that were
inadequately covered by make shift tarps etc.

Dennis replies...

My 30 or so years in the nursery and greenhouse business in northern
Vermont taught me lots of lessons in building structures that will
withstand northern winters as well. The key is a wood framework that will
shed show and ice,  with a waterproof covering, along with  lath strips and
rope lacing  to hold the whole thing in place.

My Albin 27 is easily covered by three 2x4x12's and two sheets of aspenite
particle board topped with two pieces of blue tarp (Walmart) and several
1x3x12 lath strips. Most boats can be covered with reusable lumber and
cheap tarps very adequately. A strong ridge pole need to be constructed
somewhere nearly horizontal, so snow loads can slide off and not accumulate
and be dropped into closed space on board. Use the appropriate number of
stringers, and cover them with solid 4x8 panels of cheap material. Then
cover this with cheap tarps and furring strips, and lash the whole business
down. Materials cost is well less than $100 for new material.

Last spring when we returned to Sadie B in Alpena, MI on Lake Huron, she
had already been launched with the winter cover still in place. She was
clean as a whistle (well, relatively) with no winter damage visible.
Several folks at dockside related severe damage to shrinkwraped boat's
paint and topsides work resulting from the very strong winds in late winter
there. Damage was caused by abrasion of loose shrinkwrap caused by the high
winds.

As to damage to teak brightwork, ultraviolet light levels in northern
latitudes are very much less than in summer. (Of course one would expect
this with winter day lengths of around seven hours as I recall). I never
saw any degradation of the bright work in winter, covered or not.

If I were to elect to have a boat shrinkwraped, I'd certainly have a
deadline for the work to be done. In northern Vermont, this would be no
later than October 20. After that date large snowfalls are a very likely
possibility, and it might not melt again until May 1. I distinctly remember
helping a friend salvage a swamped 24 or so foot runabout boat on Lake
Champlain in late October which had broken its mooring. It was pulled up on
shore by someone who thought he was helping, and by the time my friend got
the job, several days later the  boat was full of a large contained iceberg
something like 20x10x3 feet. That block of ice took two weeks to melt in a
70 degree garage with fans blowing on it the whole time.

This all comes to mind as the high temperature here in central Florida
today was around 58 degrees, and it felt just as cold as it ever did in
northern Vermont in mid winter!

Best wishes for all for the Holidays!

Dennis

Dennis Bruckel, M/V Sadie B
Program Coordinator
West Marine Trawler Fest
407-933-6446 land line (winters only)
407 414 0531 cell phone (year around)

Dennis replies...
The key is a wood framework that will shed show and ice,  with a waterproof
covering, along with  lath strips and
rope lacing  to hold the whole thing in place.
<<< snip>>>>
A strong ridge pole need to be constructed somewhere nearly horizontal, so snow
loads can slide off and not accumulate
and be dropped into closed space on board. Use the appropriate number
ofstringers, and cover them with solid 4x8 panels of cheap material. Then cover
this with cheap tarps and furring strips, and lash the whole business down.
Materials cost is well less than $100 for new material.

REPLY
Dennis describes a professional kind of  cover construction.
On larger boats in the 40 - 50 foot size  the weight of so many  rigid sheets
can be amount to a considerable weight.

My wooden 50 footer was covered with a traditional  cover consisting of  wooden
frames and a fitted canvas cover.
Fortunately, the previous owners  belonged to yacht clubs where storage of such
parapanelia  was possible.
Today  such storage  can be  more problematic if not impossible. At that point
you are talking about a one time use throw away shelter. that becomes even more
expensive that  professionally applied  shrink wrap.

When I needed to construct a cover for a mahogany launch that would be stored
for a number of years  before being restored, I  applied a bit of structural
engineering  to the task.
Instead of a straight  solid  ridge pole I  devised a curved ridge which  got
part of its strength from the curve rather than simply pass.
Because the launch was open it was not possible to provide any supports  on deck
and I also wanted the whole cover to be removable without  interfering with  the
interior space.

Lightweight  "T section  wooden beams spanned the width of the hull from gunnel
to gunnel and a single  "T" section beam ran the length of the hull from stem to
stern.  At  intervals  where the longitudinal beam was crossed by the
athwartships cross beams a vertical support  came up to meet the curved ridge
pole. This whole assembly  was then covered with  heavy  10 mil construction
plastic stapled to the wooden frame.
An additional thin layer of black plastic  was used as a UV block.
That cover lasted nine years.

Because I selected  good quality  wood with long runs of clear grain I could cut
the frame size to a very small cross section and  bend them into a curved shape
to resist  snow loads.  Living on the lee side of Georgian Bay in the Great
Lakes we often got  deep snow falls of a foot or more per session.
Even plastic has to be quite steep to shed  all snowfall. and if you get
freezing rain all bets are off.  Subsequent snow falls will then stick to even a
steeply sloped plastic sheet. For that reason you need to build the frame
sufficiently rigid to withstand an accumulation.
Most of us  got into the habit of doing a once a month visit to the boat to
clear off snowfall and check for any weather damage.

I estimate the curved shapes I used reduced the  weight of the framing  by half,
while at the same time increasing the strength  by a considerable amount.

Cheers

Arild

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