Is there anything that I need to consider when building a pontoon boat?

Anything as far as bouyancy? Can I have too much bouyancy? I am planning on using 55 gallon plastic drums filled with expanding foam.Is there anything that I need to consider when building a pontoon boat?
Stability, strength, seaworthiness, power, hydrodynamics. How are you going to attach plastic drums together?
Consider buying one instead huckleberryIs there anything that I need to consider when building a pontoon boat?
Are you going to put a motor on this ? more than a 5HP or trolling motor ? sounds like a lawsuit waiting to happen,,,
there is more to building a pontoon boat than

floating a piece of plywood accross the lake

for the cost you will be putting into this you can

buy a used pontoon boat even if you have to rebuild it. get one with numbers and tubes that at least are airo dinamic and wont come apart

on the lake. for a pier yes for a boat no.

visit www.discoverboating.com for info.

and www.outdoorfibber.com forumIs there anything that I need to consider when building a pontoon boat?
If you are doing this while spending less money. Try filling the drums with plastic 2 liter soda bottles. Or the smaller ones. These can be had for free. Maybe you can also find some old house doors you can use for the floor. Enjoy your boat. Please spend some money on safety stuff.
Plastic barrels can not be fastened together satisfactorily because of the flexible nature of plastic. Pontoons built from steel barrels must be welded together because the force of the pontoon going through the water will cause any bolts to tear out through the holes.

A better choice would be find a military salvage place and pick up a pair of old aircraft drop tanks. They are all one piece and aerodynamically shaped already. I have seen several pontoon boat built using those.