Please consider this as a major modification to your building structure. In my area, there are laws that govern this type of modification and require that the design be performed by a qualified professional engineer.
It is very unlikely that your house will tolerate this modification as is. An engineer will do an in depth review of the building, and work with you and your design team to determine what will be required to make the change.
There are many possibilities to make it work, but it will be constrained by your budget and the ability of the construction team.
*The civil / structural engineers will likely want a full assesment of the existing structure. Types and sizes of materials used, method of construction. For the soil they may not need to perform any test, but a geotechnical assesment of your site is highly advised (this will make sure there are no problems with the site and provide for a more optimized design of any new foundations that need to be built.)
I would recommend having a contractor (or someone very knowledgeable about construction) on your design team as early as possible. Much of what can be done will hinge on the ability of the constructors.