Leeboards: professional or 'have a go'?

Flopper-stoppers hung along the sides of the boat would be simpler and less expensive than leeboards. They also would not require alterations to the boat other than possible the addition of several cleats. Multiple flopper stoppers could be rigged along each side.
Make a DIY flopper stopper - Practical Boat Owner https://www.pbo.co.uk/practical-projects/make-a-diy-flopper-stopper-24531
Offshore Sailor: Flopper stopper - make your own http://www.offshore-sailor.com/articles/gear/flopper-stopper-make-your-own/
Rocker Stopper https://www.davisinstruments.com/products/rocker-stopper
36 in. Rock N Roll Boat Stabilizer https://magmaproducts.com/products/35-in-rock-n-roll-boat-stabilizer

 

Yes, that’s what he said, tied to a pier, also I think it was implied that it is tied to a floating pier, I wonder if that exacerbates the problem, ie nothing solid to tie up to. That’s why I mentioned anchoring.
Perhaps water is sloshing around in the bilge?
Perhaps adding or subtracting water in the bilge could help?

 

Hammerhead pontoon: in centre of marina, most exposed to the wind. Advantages... the views

 

Thank you, yes, you have described it perfectly. Bilges are dry (well until last week when 4t of fresh water from the tank were pumped into them after a burst pipe in the kitchen ) well, dry again now. Learned not to store cardboard boxes of paperwork in the bilges.
There are ballast bricks down there but they don't seem to have a massive effect if moved around. We moved half of them to port because we thought we were listing and it had no effect.

I'll check with the marina regarding laying anchors when the office opens.

 

loving the name: these are effectively my 'umbrella anchor' when kayaking! Not entirely sure i'd be allowed to deploy these though (boats pass within 0.3-0.5m of the side of the barge at times.

Thank you for the advice. I'm still smiling at the name of them.

 

Barge showing side view in moored position. Moored alongside a floating Pontoon about 25m into centre of marina. The empty water in foreground is the main thoroughfare

 

Magenta; proposed Leeboard(s)
Cyan; tarpaulin roofline

Even now the wind catching the kayak, chairs and cat cage causes significant heeling even whilst moored. Increasing the side area with the tarp and anything hung on the railings is likely to make it worse. Draft: 0.85m. Flat bottomed steel barge replica. Heel angle with breeze +/- 10⁰ measured on phone gyro and confirmed with inclinometers. Boat Rock solid without a breeze though

 

Do the prevailing westerly winds blow you on to the pontoon, or off it - or is the barge facing west?
If the winds are blowing you off, and the pontoon is floating, would it be feasible to have some snug breast ropes between the barge and the pontoon, to try to limit the heel angle? These ropes would have a lot of tension in them though - would the cleats on the pontoon be strong enough if you tried this?

 

Thank you:

Wind direction varies enormously, there is no "prevailing" direction . Can change 180 over the course of an hour and then back again. The marina is 100% tall buildings along one edge and warehouse but low level in comparison on the other and also acts as a wind tunnel along the river. Butterfly wing effect somewhere

 

A tall mast would help slow down the motion, and could be equipped with a sail or kite to help.
The variable winds are obviously a problem!
You might wish to look for a more sheltered mooring, as viable temporary solutions aren’t showing up.
I’m still having trouble imagining how such a large, flat bottomed hull is acting so lively.
My best conclusion is that it needs more ballast.
Easy to experiment with that by temporarily flooding the bilges.

 

It's MV not a sailing badge therefore no mast. Ingesting thought about flooding the bilges; as mentioned previously 4t from the fresh water tank flooded the bilges last Thursday... it did not dampen the motion but it did dampen everything I'd stored in the previously perfectly dry bilges.

Thank you for the suggestions.

 

Where are said 4T water tanks located? Are they baffled to prevent sloshing?
They should be in the bilge, but if they’re up high for gravity flow, could be exacerbating the problem.

 

4t Bow tank, yes baffled, 50% above and below what I would consider CoM longitudinally. 2t secondary tank baffled filled with bleach/water, unused midship in the bilge.

When the bow tank was emptied into the bilge by broken pipe and before the bilge was emptied, we were more unstable, definitely listng to starboard more and once started, that's where the water collected and made it worse. . Was a still day so I couldn't comment on any motion. Filling bow tank before emptying bilge didn't seem to affect much, emptying the bilge just allowed us to be more even again.

Thank you for your interest. The people on here are great!

 

The load carrying capabilities of a flat bottomed barge is huge, but I’m thinking your vessel may represent a “light” condition when compared to the actual design load of the hull.
This would explain it’s tenderness.
Have you done any loading and stability calculations?