Blueprints
I made an initial phone call to my county's building department to learn what was required to build my own garage. I was fearing the worst, because the red tape that these departments sometimes impose can be overwhelming. They told me that if I used post and beam construction I would definitely need engineer stamped blueprints. However, they said that there was another alternative that did not even require blueprints or the services of an engineer...
My state of Colorado has a set of garage construction plans on its web site that I can download, fill in some information, and submit to the county for my permit. I found the state garage plans to be extremely helpful in understanding what I was doing, so take some time to download and print this plan just to see how it all works:
The basic idea of this plan is that you have a poured slab foundation (meaning, your garage has a concrete floor that also serves as the attachment point for the garage walls). You can fill in the details of the foundation, whatever lumber you will be using for the walls and roof (whether you use trusses or rafters), and specify door and window openings.
After studying the plans for a long while, I called the community development office again and asked how large of a garage I could build with these plans. They said that the maximum was a 24x24 2-car garage. Well this was all fine and well except that I wanted a 3-car garage, with an oversize door for parking my large pickup truck or a camper. I thought for a long time about sacrificing what I wanted in order to avoid engineering, but in the end I decided to build what I wanted the first time. So, I obtained from them a list of engineers who were familiar with the construction guidelines in our county.
One talk with a local engineer who lived in the mountains confirmed that post and beam construction was not a sensible choice. The expense of the lumber needed to have a building properly engineered for my weather conditions just didn't make sense. It required too much precision to get everything right, because the support of the structure was concentrated in just a few areas that had to be perfect. It was not something I would be able to do myself if I had to.
I wasn't sure who was going to do the actual work at this point, but it was looking like I was going to be doing as much as I could possibly handle. I liked the ideas that the engineer had. I was insistent that I be able to do all parts of the project myself if I had to, and the engineer said that he could come up with a plan that would be so easy that anyone could follow it.
Site Survey:
We were able to scope out an exact location for the garage based on the lay of my yard and our foundation ideas. We also discussed setback requirements and made sure I had plenty of setback, so that I didn't need an expensive site survey. A detailed site survey is required if the garage is located close to a property boundary. By keeping the garage more than 40 feet away from any estimated boundaries, I was able to avoid the site survey, saving about $2,000.
Foundation...
One issue was that frame construction requires a lot more in the way of a foundation, compared to post and beam construction. The engineer recommended a solid concrete slab floor and foundation. I asked him about the cost, it seemed like it would be insanely expensive to haul that many yards of concrete up to my house. He agreed. What I did have though was a full size heavy duty pickup truck. One that could carry large heavy pallets of concrete block up from town. So the decision was made that the foundation was going to be constructed of 8x8x16 concrete block, with rebar and all of the ports in the blocks filled in (most areas of the U.S. only require every other port to be filled). The foundation would run around the perimeter of the garage and the floor would be dirt. Sounded good to me.
Roof...
The engineer said I would want to use pre-built trusses for the roof structure. A "truss guy" would come out and spec the trusses when the time came. They would then deliver the trusses and I would have to figure out how to set them on top of the wall framing. I asked about the shape of the trusses, and he said that normal trusses are basically triangular.
This posed a problem for me. I wanted my garage to have one door that was a lot higher than the others. This is because I wanted to be able to park a small camper in one of the stalls. If the trusses had a beam running across the tops of the walls, my walls were going to have to be extremely high to clear my tall garage door. The engineer said that one possible way to handle this was to use scissor trusses. The scissor trusses are shaped differently so that they have a very high clearance underneath the middle. We could then put the tall garage door in the middle. Unfortunately they are a lot more expensive than standard trusses. We talked about cost once again, and he agreed that having scissor trusses spec'ed, built, and delivered to my area would be very expensive.
He said the next option would be to have the tall garage door be the one in the middle, just like in the scissor truss plan, but have posts in between the garage doors that would support large beams, which would in turn support conventional roof rafters. It would be something that I could build myself and wouldn't cost a huge amount. Party on!
Blueprint Time...
The engineer said he would create and stamp the blueprints so that I could get my building permit. He also said he would make the blueprints as clear and complete as possible since he knew I hadn't done anything like this before.
I provided him with a current site plan of my property, which showed the house, existing outbuildings (an old shed), the well, and septic system. We went over some details of the construction so that I understood what his plan was going to look like.
We finally had the needed information worked out to create the blueprints, and in about a week I had the prints in hand and was ready to move forward.
There were 2 large copies and 2 small copies of the prints, and they included the site plan which he added the garage to. Only one of the large copies was actually stamped with the engineer's stamp, similar to a Notary's stamp. That large copy and one small copy were what I needed to send to my county building office with my permit application. And one of each copy stayed with me.