Hull Size

To determine the hull size of the ship, add up the volume of all the components, accommodations and vehicle bays.  Don't add in the cargo bays yet.  This gives you the total volume of the ship systems in the inhabited portions of the ship.

Next we need to add in space for the various control centers of the ship (bridge, engineering, combat centers, etc.) and passage ways.  For simplicity we'll assume that these spaces add 25% to the existing volume of the ship's systems.  So the total volume of the inhabited portion of ship is determined by multiplying the volume of all the components by 1.25.

Finally to get the total ship volume, we add in the volume of the cargo area. 

Once we have the total volume of the ship, we can compute the hull size (maybe or simply look it up on the chart below).

The ship's hull size will determine things like it's Hull points, the number of ships that can be mounted externally and the numbe of engines it can support.

Now that we have the hull type and total volume, we can calculate the cost and mass of the hull.

<hull cost values go here, it should go up based on the volume >