I mentioned on the Tiny Houses Australia Facebook Group page that I would document my knowledge of CAD (computer aided design) and how it relates to the tiny house building community, well here it is. Hope it helps.
Okay, full disclosure, I work for a CAD software reseller, I have done for nearly 3 years. If you think this article is in any way bias please let me know and you have my permission to give me a big pinch on the arm.
Let’s face it, most of what you can do with CAD software you can do with a pencil and a ruler and for many centuries before that people just made stuff by eye. Where the CAD software gives you an advantage is in speed. So the first aspect to think about is how quick you need to get your design done and then ask yourself how far through the design process you want to go.
A more thorough explanation of CAD can be found at http://en.wikipedia.org/wiki/Computer-aided_design
Typical design process stages in Tiny House building
Discover a need – e.g I want to live tiny
Capture requirements – e.g. I want it to sleep 3 people
Research design options – e.g. which materials you want to use
General arrangement – what goes where
Engineering and architectural design – precise measurements, load calculations
Manufacturing instructions – layout drawings, finishes, tolerances, standards
Let’s look at some definitions
CAD software comes in two basic flavours, 2D and 3D
2D means when you draw you only enter X and Y coordinates, you can still draw something viewed from an angle but it is very difficult.
3D means you can enter a Z coordinate which might be depth or height
And these can be broken down further, see later
So how does this affect the tiny house designer?
I feel that most people reading this are looking for something very cheap (under $100) or free that turns their 2D sketches into a 3D view but at the same time are not designing for manufacture. By that I mean they’re not thinking about every nut, bolt and screw. If you are though you need to be looking at the semi-pro or pro level.
The further you move down the following list of software the more time you will have to devote to learning how to use them, also the more powerful a machine you will need to run it. But it also means that designing will be faster, balance that with the fact that the more expensive they become.
So the sky’s the limit and there’s no such thing as a free lunch. If it doesn’t cost you money it’ll cost you time. And unless you are building it by yourself and for yourself you will need a good set of plans generated by at least a semi-professional.
Let’s look at the main players in the industry (Beware: free and cheap software tends to come and go, you may be left having done work you can’t use later on)
Free (non-technical – amateur/rookie designer)
Sketchup, surface modelling only, architectural visualisation mainly http://www.sketchup.com/
Blender, surface modeller used mainly for character animation http://www.blender.org/
Tinker CAD, browser based https://tinkercad.com/
Very cheap (non-technical/non-professional, design enthusiast)
Cheap (semi-professional – small workshop, 1-man band)
sketch-up $590 per year includes layout drawings
autocad $1200 per year, some 3D surfacing functionality
Mid-price (semi-professional/professional – small/medium business, 1-5 design staff)
Design & draft $1200 per year, basic modelling and drawings
Solid Edge $2400 per year, advanced modelling, sheet metal, framing, materials, motion, physical properties
Solidworks, Inventor, both similar to Solid Edge
Top-end (professional – factory assembly line)
NX $5-10,000 per year, automotive standard
CATIA, similar to NX
Types of 3D software
3D wireframe, means lines that join X, Y and Z coordinates together
3D surfacing, means filling an area between 3 or more coordinates with visual information
3D solid, means the software recognises the shape and can apply density and other attributes
Solid modelling can also be broken down into direct and parametric methods
Direct modelling means you can manipulate a face by selecting it and manipulating it
Parametric solids are generated using sketches which can then be manipulated
Any questions about this article please drop me a line