Since a custom winter cover is fairly expensive, you will want to consider it carefully - particularly if you don't reasonably think you'll keep your boat 5 years or more. Depending on the size of your boat and the complexity of the cover made, you'll normally recover the cost (compared to shrink-wrapping) in 2-3 years.
While this is mostly targeted at sailboat owners, most of what is discussed is applicable to power boats as well.
Mast Up or Mast Down?
Mast Down
If you always lower your mast or it is easy to do with a couple of helpers, mast down is always your best bet. This is because the mast provides a strong "ridge pole" which runs at least the length of your boat.
Depending on your rig, this can be as simple as letting it lie along the center line of the boat resting on both bow and stern pulpits. If you don't have both pulpits, you can rig a crutch for either end. You can also rig crutches at both ends and raise the level of the mast. This is often desirable to give the cover a steeper pitch to prevent pockets of snow accumulation.
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| This Cal 30 is equipped with both davits on the stern and a mast pulpit. By making a crutch the same height as the mast pulpit, the horizontal mast has additional height allowing a steeper pitch to the cover. Note that the mast ends are enclosed in "socks" which seal the ends of the mast, prevent birds from building nests and provide ventilation with a mesh bottom (end). |
The complexity of your cover depends on how much work you are willing to do in preparation for installing it each fall. Specifically, you may need little modification to the basic cover "blanket" if you take down your lifeline stanchions. If you leave them up, no problem, but the cover will need to be equipped with a slot for each stanchion and suitable method of securing the slot and providing a seal at the top.
The simplest mast down cover (outside the deceptively inexpensive tarp or tarps) is one that encloses both bow and stern pulpits (usually with zippers, 1/4 turn fasteners) or some other closure.
Mast Up
A mast up cover is normally made in (at least) two sections and one junction matches at the mast with a zipper that runs down each side to the toe rail. The slot in the shape of the mast cross section is enclosed with a boot - usually laced around the other (like that typically done on a mainsail cover where it attaches to the mast).
Then, slots must be made to accommodate all of the pulpit legs that will go through the cover, lifeline stanchions, fore stay, back stay, shrouds and any other obstructions. The construction of the cover is nearly identical to a mast down with the added complexity of all of the necessary slots and corresponding closures.
The mast up cover is desirable for those who never bring their "stick" down and gives a strong cover that usually serves for 10-15 years.
Framing
For all mast up covers and many mast down covers, strong framing is needed to give the needed pitch to the cover and support the weight of the cover and any accumulated snow loads.
For a mast down cover needing additional framing, this is usually just one or more crutches - that are well braced and secure - to hold the horizontal mast at the desired height.
For mast down covers, the framing usually supports both ends of the boom so that loads are not supported by the topping lift and provides either a horizontal or slanted path from the forward side of the mast down to either the bow pulpit or deck at the bow.
In some cases, it is desirable to place a large PVC pipe over the end of the supported boom to extend it aft and simplify the construction of the cover near the stern. In all mast up covers, however, the boom itself is used as a horizontal frame going over all or part of the cockpit area. For the area forward of the mast, wood framing can be used or a spinnaker pole can be employed.
In nearly all cases, this framing is a one-time expense as it can be reused year after year.
Materials
Your choice of the material used for the cover will depend on cost of fabric, severity of winter conditions and, to some degree, aesthetics.
While the most practical of use may think that a cover needs to be rugged, durable and functional only, I think that it is a shame not to make it colorful and (dare I say) pretty as well. The amount of fabric that you will use - and the corresponding cost - won't vary whether you use all one color, two colors and whatever combination you like.
The following shows an assortment (but certainly not all) of the popular fabrics that are suitable for winter covers. Along with pricing differences, there are plenty of other things to consider when selecting a fabric. If you are trying to estimate the amount of fabric that it may take for your job, please remember that you need to consider fabric width - 1" for overlap to determine how much of the length of your boat will be covered by one panel.
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| This cover used about 36 yards of the Brown fabric and 5 yards of the Maroon. With this fabric (Shelter-Rite) it could have been made in any combination of these colors: ShelterRite Colors. When it comes to color choice, there is no penalty for making your cover striking and unique. |
Shelter-Rite - $14.95/Yd.
When it comes to ultimate durability, chafe protection and tear resistance, this material comes out on top. While its cost per yard is fairly low, it does not "breathe" and venting to allow air circulation must be included in the design of the cover.
Shelter-Rite is a tough, waterproof, vinyl-coated polyester fabric with a matte finish on the outer side. This fabric is designed for high performance and flexibility; use for tough applications where high tear strength, high tensile strength, high adhesion, and exceptional weather resistance are main applications. With a high abrasion and tear resistance, Shelter-Rite is perfect as chafe protection - protecting and reinforcing worn or stressed areas. Use Shelter-Rite on heavy-duty protective covers, around grommets & trampoline edges, tenting, tailgate curtains, truck & industrial tarps, heavy duty bags, hurricane shutters, and gym mat covers.
Special Features
- Highest UV Resistance
- Highly Abrasion Resistant
- Waterproof
Specifications
| Width: | 61 inches |
|---|---|
| Weight: | 18 ounces per square yard (30.5 oz/linear yd) |
Sea-Mark - $28.95-$35.95/Yd.
Item Description
SeaMark Waterproof Fabric is a premier boat exterior fabric consisting of woven acrylic facing and color-matched waterproof PVC backing; a combination that results in a colorfast, waterproof fabric laminate that can withstand the harshest conditions of any marine environment. This vinyl-backed fabric has superior seam and tensile strength and is di-electrically sealable. SeaMark fabric is engineered to endure salt, moisture, sun, wind, and temperature extremes: it is UV and Mildew Resistant for exceptional boat exterior performance.
SeaMark is an exterior marine grade fabric specifically designed for outdoor use. There is a right and wrong side to this fabric, meaning that only the facing side, or acrylic canvas side, of the SeaMark is meant to be exposed to the outside. The vinyl backing is color coordinated with the acrylic facing. Use SeaMark Waterproof Fabric for convertible & boat tops, dodgers, biminis, tonneau & boat covers, awnings, and cockpit cushions.
Specifications
| Width: | 60 inches |
|---|---|
| Weight: | 15.6 ounces per square yard (26 oz/linear yd) |
Features
- Facing: 100% Solution-Dyed Acrylic fabric
- Backing: 100% Waterproof Vinyl (Embossed PVC)
- UV Resistant
- Mildew Resistant
- Excellent Tear and Tensile Strength
- 5 year Limited Manufacturer's Warranty
Special Features
- Highest UV Resistance
- Highly Abrasion Resistant
- Waterproof
Sunbrella - $21.95-$28.95/Yd.
Sunbrella Marine ColorsItem Description
Sunbrella 4637-0000 Forest Green 46" is a solution dyed acrylic from Glen Raven's Sunbrella Marine Grade collection that is considered the standard cover cloth in the boating industry because of its fantastic color options, high resistance to fading, and long life span. Sunbrella is a soft, breathable, solution-dyed acrylic that is UV, water, and mildew resistant and does not noticeably shrink or stretch. Both sides of this marine fabric are the same, meaning that either side can be exposed to the outside. In addition to being the best outdoor fabric, Sunbrella acrylic fabric is easy to sew! Sailrite is proud to carry the best in solution dyed acrylic cover fabric!
Sunbrella Marine fabric is intended for outdoor use but is also suitable for indoor applications (although not as soft as Sunbrella Furniture Fabric). Sunbrella Forest Green is perfect for awnings, dodgers, biminis, sun bands, boat tops, sail covers, other outdoor covers, outdoor furniture, cockpit cushions, and enclosure curtains.
Recommended Uses
| Marine: | AwningsBiminis & T-TopsBoat CoversDodgersExterior CushionsSacrificial Sail CoversSail BagsSail CoversWeatherclothsWindshield Covers |
|---|---|
| Outdoor Living: | Awnings |
| RV & Auto: | Awnings |
Special Features
- Highest UV Resistance
- Highly Water Resistant
Specifications
| Width: | 46 inches |
|---|---|
| Weight: | 9 ounces per square yard |
Features
- 100% Solution Dyed Acrylic
- UV Resistant
- Water Resistant
- Mildew Resistant
- Breathable to Prevent Condensation
- Minimal Shrinking or Stretching
- Fade Resistant
- Stain Resistant
Sunbrella Plus - $32.95-$34.95/Yd.
Sunbrella Plus Marine ColorsItem Description
Sunbrella 8443-0000 PLUS Persian Green 60" is a solution dyed acrylic from Glen Raven's Sunbrella Marine Grade collection that is considered the standard cover cloth in the boating industry because of its fantastic color options, high resistance to fading, and long life span. Sunbrella is a soft, breathable, solution-dyed acrylic that is UV, water, and mildew resistant and does not noticeably shrink or stretch. In addition to being the best outdoor fabric, Sunbrella acrylic fabric is easy to sew! Sailrite is proud to carry the best in solution dyed acrylic cover fabric!
Sunbrella Plus fabric has an additional urethane coating for even more moisture and abrasion resistance than classic Sunbrella. Sunbrella Plus marine fabric is intended for outdoor use only, use coated side down. Sunbrella Persian Green is perfect for for awnings, dodgers, biminis, boat tops, and enclosure curtains.
Specifications
| Width: | 60 inch |
|---|---|
| Weight: | 10 ounces per square yard |
Features
- 100% solution dyed acrylic
- UV resistant
- Water resistant
- Abrasion resistant
- Mildew resistant
- Minimal shrinking or stretching
- Fade resistant
- Stain resistant
Surlast - $13.95-15.95
Surlast ColorsItem Description
Surlast is an all-weather fabric, woven from 100% solution-dyed polyester that offers great protection for anything outdoors! Surlast from Glen Raven was originally developed for the marine industry to endure the stress put on boat covers, but it is quickly becoming the standard for automotive and motorcycle covers, as well as accessories. Surlast fabric is a tough, non-abrasive polyester fabric with excellent weather & abrasion resistance and good breathability.
Surlast is solution-dyed fabric; meaning that the color, UV inhibitors, and stabilizers are actually a part of the fiber and cannot be separated. The result is a strong, long lasting fiber with rich color that will not fade, wash out, or transfer to your gelcoat when trailering. A urethane coating is added to one side to provide additional stability, increase water and mildew resistance, and minimize shrinking or stretching. The coating also keeps this outdoor fabric from raveling for easy construction - no hotknife required!
Surlast fabric is designed specifically solely for outdoor use. Use Surlast Fabric for boat covers, PWC covers, automotive and motorcycle covers & accessories, storage covers, sail bags, and packs. There is a right and wrong side to this outdoor fabric, meaning that the uncoated side of the Surlast should be exposed to the sun.
Specifications
| Width: | 60 inches |
|---|---|
| Weight: | 7 ounces per square yard |
| Denier: | 600 x 600 |
| Break Strength: | 350 pounds (Warp) 275 pounds (Fill) |
| Tear Strength: | 40 pounds (Warp) 35 pounds (Fill) |
Top Gun - $18.75-$19.50/Yd.
Item Description
Top Gun is the ultimate acrylic-coated fabric that provides unrivaled durability, as well as superior tear and abrasion resistance. Woven from 100% polyester, this 600 denier fabric utilizes a proprietary coating process on both the top and bottom, making it completely reversible. The special formulated acrylic coating will not crack or peel, even in extreme heat and subzero temperatures. Top Gun is an exterior marine grade fabric, excellent for heavy long-term trailering or winter covers, biminis, t-tops, and dodgers. It can also be used as chafe reinforcement for highly abrasive areas.
Specifications
| Width: | 62 inches |
|---|---|
| Weight: | 11.5 ounces per square yard |
| Tensile Strength: | 500+ lb/in (warp), 388 lb/in (fill) |
| Tongue Tear Strength: | 43 lb/in (warp), 32 lb/in (fill) |
| Spray Rating: | 90+ |
Options & Features
You have plenty of choices on how much (or little) you want to customize your cover to make it easier to use, improve access or make it more rugged for severe weather conditions.
Venting
This is a must for any of the rugged materials that don't breathe. Its not as much of an issue in the cold north as the humidity stays very low. The most common vent is a hole in the cover covered by a rodent/insection proof screen and a scoop cover to keep out moisture.
Much below southern Indiana or so, you'll want to consider adding some ventilation in any cover. For covers that are mast down, you can also consider making ventilated mast socks which allow free flow of air into and out of the cover.
Windows
If you like to do post or pre-season projects on the boat, adding two or more small windows will let in an amazing amount of light without detracting from the main functions of the cover. These can be in any shape, although both triangular and round are gaining in popularity.
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| This cover offers four windows. While all are triangular, they can be located wherever you like and oriented differently as well. Some of these are sewed directly to the cover while others are glued in place. This is a nice feature of this Shelter-Rite material. |
Chafe Protection
One some covers, a layer of Shelter-Rite is often added along the whole length where the cover make contact with the rub rail. In others, it is only needed in areas where the cover has a "bump" due to a winch, dorade box, mast pulpit or any oother obstruction in the slope line from the framing to the toe rail. In the picture shown above, a large, padded chafe patch has been added to accomodate a mast pulpit structure. There are either just an additional layer or two of material or can be a padded vinyl coaster sewn or glued in place.
Zippers For Joining Sections
On any mast up cover, we normally have at least one zipper that joins the bow and stern sections and provides a "boot" to secure them to the mast. While it isn't absolutely necessary in a mast down cover, it is a good idea as it makes installation (particularly of covers made with heavier materials) much easier.
In this cover, we have two zippers to separate the three sections. This cover was made with the possibility of conversion to a mast up (with further slots needed and other modifications), so the zipper at the center is actually two zippers that run from the (currently uncut) mast hole down to the rail.
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This cover is in three sections with a two-piece zipper at the center of the boat (corresponding to mast location when up) and a second which is in the cockpit area.
Zippers For Access
While not absolutely necessary, we rarely make a cover without providing access to the boat without any cover removal. This is usually done with a "smile" zipper which allows a large, curved access.
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| This large smile-sippered access makes getting on and off very easy and the rest of the cover doesn't need to be disturbed. Shown folded back over the mast is the additonal storm flap that is secured with six 1/4 turn (common-sense) fasteners. |
Zippers For Securing Sides
In this cover, we use a zipper (to zip "down" in both cases) at both the bow pulpit and to allow installation of the stern portion of the cover around the obstructions at the stern pulpit.
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| This zipper secures the triangular piece the encloses the aft portion of the cockpit and provides ability for opening for ventilation without disturbing the rest of the cover. |
Methods For Closing the "Slits"
Bow pulpit, stern pulpit, forestay, backstay, shrounds, lifeline stanchions and other obstructions to the "slope line" of the cover must have a hole made, a slit to bring down to the rail and then some method of closing the slit when the cover is draped around the obstruction.
While this can be done in many ways - including laced grommets, velcro or snap fasteners, we find that using either zippers (with an optional storm flap or not) or a flap with 1/4 run fasteners present the best methods.
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| With the presence of the stern pulpit, additional vertical support stanchions and dinghy davits on the stern of this boat, there needed to be 7 slits to be closed to allow the installation of the aft section cover. Note the zipper which runs up to the underside of the horizontal mast. |
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| Most of the other slits on this cover are closed with a flap having one, two or three 1/4 turn fasteners. |
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| The "hole" area at the top of the slit may also need some weather protection. While boots can be sewed on each, this is a much simpler method. |
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A separate piece like this "lampshade hat" can serve to keep snow from the holes at the top of each slit and are made in quantity to lace around each stanchion, shroud or pulpit leg.
Comments or Questions?
We'd love to answer any questions or take any comments about this topic.
You can contact us through the forum, email to mcc@mascom.com or fill out a comment on this blog.
Greg Murphy
Mascom Canvas Crafts
616-304-2345
