# Adding a cabin on boat

Discussion in 'Stability' started by Nathan246, Mar 10, 2018.

1. Joined: Mar 2018
Posts: 7
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Location: Australia

### Nathan246Junior Member

Hi all I have recently acquired a ski/fishing boat and have removed floor to get stuck into replacing the stringers as they are rotted. I need to remove the top section of the boat to get to the bow, my question is while it is off I was thinking of making a hard top for it but don't know what it would do to the stability of the boat being that the hard top will be top heavy. Thanks in advance

2. Joined: Mar 2018
Posts: 7
Likes: 1, Points: 3
Location: Australia

### Nathan246Junior Member

￼This is the boat in question it is 17 ft v bottom

3. Joined: Sep 2011
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Location: Spain

### TANSLSenior Member

If the end result is that the center of gravity increases, for the same displacement the initial stability (initial GMt) will be lower. But without knowing the current boat shapes and what you want to do, with the changes / addition / reduction of weights it is not possible to say anything concrete. Could you give more details of the transformation that you are thinking?

4. Joined: Mar 2018
Posts: 7
Likes: 1, Points: 3
Location: Australia

### Nathan246Junior Member

I was thinking of something like this just to have some more storage area and get out of the rain if needed

5. Joined: Sep 2011
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Location: Spain

### TANSLSenior Member

Calculate the weights to be deducted and the weights to add, with their centers of gravity. You should also estimate the situation of the new flotation, at least if the breadth in the flotation increases, decreases or does not change. All that could give an idea of where things are going.

6. Joined: Mar 2018
Posts: 7
Likes: 1, Points: 3
Location: Australia

### Nathan246Junior Member

Ok no worries I will figure out how much fibreglass I will need and add bracing where needed, I figure it should be alright considering smaller boats have that design and do just fine on the water. Thanks for your help

7. Joined: Nov 2012
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Location: Delta BC

### JSLSenior Member

The boat is small (17') so even if it can handle the topside weight of a hardtop, avoid additional weight for the time being. Many 'hardtops' may also be fitted with additional weight items like grab rails, rod holders, running lights. antennae, electronics, etc etc.

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