Computer Aided Drafting with Rhinoceros

You can definitely build your own home using building plans that you purchase from a certified architect, but if you really want to Save Sustainably you should really create your own plans.  This will eliminate the cost of the plans and allow you to customize endlessly, maximizing the efficiency of the home.  My priorities in designing a floor plan were to minimize costs by keeping the shape simple and the dimensions in increments of 4 feet.  Nearly every buiding supply from lumber to plywood to drywall comes in increments of 16 inches, 24 inches, or 48 inches.  If you design on 4 foot dimensions you can account for all of these measurements, reducing the need to make cuts and throw away perfectly good building material.  The sad truth is that the number of architects with a building background is practically zero.  They are interested mainly with aesthetics and ease of use, which are surely important, but must be balanced with building and engineering costs.  The only practical way to get a house design with all of them in mind is to do it yourself.

Creating construction plans isn’t nearly as hard as you might think.  Once again, the county office has all of the information you need.  If you’re lucky, they have a significant online presence and you can find all the information you need on the web.  The county code will clearly spell out what kind of information needs to be included with your documents, usually site plan, elevation plan, electrical plan, foundation plan, floor plan, and detail plans.  I would suggest obtaining a set of full construction documents from a library or contracting friend to get a sense of what these plans should look like.  I will also be posting my plans here as well so that will give you a general idea.  Here I have a rough site plan that I submitted for Septic Design.

While it is perfectly acceptable to draw your plans by hand, artistically challenged people like myself may find it much more efficient to learn how to use CAD, or computer aided drafting.  CAD programs to choose from are numerous, but unfortunately almost all of them are pretty expensive.  I was lucky enough to have a fiancee attending graduate school at the time so I was able to use her student edition of a particular CAD program called Rhinoceros.  The student price of Rhino is a bargain compared to the competition at $195.

What separates CAD programs from simple software like MS Paint, for instance, is that each individual line in a CAD drawing is represented by a mathematical formula.  This allows you to manipulate them and give them dimensions in ways that simple drawing programs are unable to do. CAD drawings are broken down into curves, surfaces, and solids.  A curve could be a straight line, or a circle, or a box.  You can join different curves together, and when several “open curves” all connect to each other at both ends you have a “closed curve”.  A surface is formed from the area enclosed by a closed curve.  If you need a visualization, a picture frame would be a curve and the actual picture would be the surface.  Two dimensional surfaces can be “extruded”, or stretched out into a 3rd dimension.  Several open surfaces that are connected on all edges can be joined together to create a polyclosed surface.  A polyclosed surface that is solid on the inside of it is called a solid.  Again, for a visualization, a basketball would be a polyclosed surface and a bowling ball would be a solid.

You can actually create construction documents by simply using curves, text, and a dimensioning function, but I wanted to go far beyond that.  I learned during my training time that building a house can quickly become a headache if it isn’t thoroughly planned out.  Construction documents are not, as I ignorantly thought they were, instructions for building a house.  They are merely documents that give the building inspector and contractors a basic idea of how the house should be built.  The contractors use the plans to know what the finished product should look like, but use their experience and improvisational skills to figure out how to get there.  As a beginner, I’m lacking in both of those departments.  This is why I have been basically “building” the house on my computer screen before I break ground in the coming weeks.

If you bypass this important step, you can come across a LOT of unnecessary problems.  For example, after you pour a cement foundation, nearly all building codes require you to attach the wood frame of the house to the foundation using large anchor bolts with square washers and nuts.  These bolts must be spaced out according to local codes, usually a maximum of 6 feet apart from each other and a minimum of 12 inches from the end of each board that makes up the bottom of the wall (called a bottom plate).  If you don’t plan out this spacing in advance, one of these bolts could end up where a wall stud attaches to the bottom plate.  You would have to shear off the bolt, drill a hole in the concrete, buy another bolt, and reattach the bottom plate.  You just wasted a ton of time and money because you didn’t plan things out.  This is merely one example of hundreds that can occur throughout the building process.

Many CAD programs include free online training courses that are free with purchase of the program.  Buy one, learn it, and use it.