Leaky bimini top

[keith c]

Having leaks in my canvas bimini top. Need suggestions on how to treat it.

 

[caltexflanc]

It's likely coming from the seams. You can try spraying with a waterproofing that is used for camping tents, available at most sporting goods stores. Do you know what the fabric is? Sunbrella recommends 303 products. But if the seams are shot, sprays will have limited effectiveness.

 

[koliver]

Having leaks in my canvas bimini top. Need suggestions on how to treat it.

Your top is most likely made of Sunbrella, that being the most common Bimini top material. Sunbrella will last in constant exposure to UV, for between a decade and 2 decades. The threads used in sewing your Bimini will often be ordinary, non UV proof thread. Better Bimini sewers use "Tanera" thread, which, at a higher price, last almost as long as the Sunbrella material. If your leaks are all at the seams, threads are the first suspect. If not at the seams, the Sundrella fabric itself is the culprit.
Remedies: If you are confident that the fabric is still OK, get it restitched. If your leaks are through the fabric, a waterproofing coating, such as Thompsons Water Seal will give you a few years of respite, but replacement is in your future.

When I bought my boat, in 1994, the tonneau cover had been in constant exposure to UV for about 5 years and in summer-long exposure for another 10. Within a year or two I used Thompsons Water seal and extended the life of that bit of canvas another 5 to 10 years. At that age, I replaced it.

As for the Bimini,I am facing this hard choice myself. My Bimini is at least 30 yrs old and the seams are beginning to fail. In addition, I can see through the fabric, away from the seams, in a few places.

I have checked the cost of fabric and of a replacement kit at Sailrite.com. They provide excellent instruction, if you have access to the proper sewing equipment and the skill set to DIY. Their fabric is currently $22.95/ yd. Their kit costs about twice that, but you get the zippers, seam binding tape, webbing and detailed instructions in the package, together with video instructions and a phone help line that is the best I have seen.

If you don't wish to attack the Bimini DIY, replacement is the core business of many shore facilities. Get some estimates and look at their work when you choose a vendor.

 

[fryedaze]

Make sure you get the right 303 product. I once put 303 protectant on Sunbrella. Took me a while to figure out why the sunbrella still leaked. 303 Waterproofing.

 

[Redhook98]

Believe it or, Thompsons Water Seal works the best. Yes, the stuff you put on your deck at home. Either paint it on or get the spray can. My upholstery guy told me that and I did not believe him. Tried it on a whim one day and it was perfect. Its a lot less money, and lasts a lot longer. Dries with some white residue, but that washes off in the first rain. I've used it on turquoise, Capt Navy blue and tan Sunbrella. No problems.



Just like anything else though, try a small sample on a corner or a scrap if your uneasy about it.

 

[rgano]

There was a comment on another thread about simply adding another layer of water repellant material through the use of twist-locks. Easily removed for cleaning etc. Just a thought.

 

[Comodave]

We replaced the canvas bimini with a hardtop. No more leaks.

 

[boomerang]

Our bimini still looks good and I had the stitching & a zipper replaced but it let rain pass through like a screen door. I figured I would give the waterproofing treatment a go before I sprung for new canvas. I bought a gallon of Star Brite waterproofing because thats what West had on the shelf.
I stuffed the thing in the washing machine on the "heavy bedding" setting, hung it on a line to dry and then applied 2 applications with a recycled windex sprayer. I'm a skeptic of most snake oil but I'm happy to endorse the stuff! I don't know how long it'll last but it's been keeping 100% of the rain out for several months now.

 

[Larry M]

Our bimini still looks good and I had the stitching & a zipper replaced but it let rain pass through like a screen door. I figured I would give the waterproofing treatment a go before I sprung for new canvas. I bought a gallon of Star Brite waterproofing because thats what West had on the shelf.
I stuffed the thing in the washing machine on the "heavy bedding" setting, hung it on a line to dry and then applied 2 applications with a recycled windex sprayer. I'm a skeptic of most snake oil but I'm happy to endorse the stuff! I don't know how long it'll last but it's been keeping 100% of the rain out for several months now.

We used the same stuff with good results. Had to re-coat every six months or so but it was a lot cheaper than the alternative.