The question could also be, “what was a viga?” Why not start there first. The answer is simple and pretty obvious, a TREE, turned into a beam.
Now that we got that out of the way, let’s talk about the kinds, the use, where there used and why. Let me say first of all, I’m not a viga expert, not sure if there is one to be honest and I’m sure there are some who could add to what I know. Even so, here is what I do know.
These tree trunks are primarily used in the southwest part of the USA. If you google “What is a viga”, it seems that most of the answers say “beams used in an adobe house”. That definition is true, viga by definition is a beam, but used in an adobe house is to limiting. Vigas are used these days in primarily adobe “looking” homes. In other words they are mostly and commonly used in stick frame constructed buildings. Historically dating back to who knows when, if you wanted to put a roof on your home, you’d chop down a tree, take off the bark, lift it up onto your (most likely) adobe walls, (with the help of a bunch of your friends cause their heavy) and there you’d have it, the supporting roof beams or vigas for your home. This process is still done today (except your friends know better and won’t volunteer) so your hire a guy with a crane to lift them up and place them for you.
I have designed and built several homes with vigas as roof supporting members and used as decorative beams also. When used as structural load bearing beams a person should take care to size them according to their span from wall to wall and the load they are going to support. I personally over-sized the vigas in the homes I built because I thought they looked better, stronger. I would always stain them and seal them, but there is know real need to do either.
When I first started to build my own homes in Santa Fe, New Mexico, I would use pine vigas right out of the lumber yard, YUK! After having to caulk or re-plaster around them where they had shrunk because of the large amount of water in them, I gave up the lumber yards version of a viga. I can remember one house I built. The electrician was drilling a hole straight up through the viga to put a light fixture in to hang from the viga, water came pouring out. I literally couldn’t believe it. We both stood there watching it drip. So when I said that’s it I’ve had enough and decided to do something about it, it was kinda like going from fast food to fine dining. How did I do this? One day while driving around looking at other builders homes one Saturday, I came across a guy unloading vigas at a job site, so I pulled over to talk to him. That was one of the best things I have ever done concerning my building techniques. After introducing myself and talking awhile, I asked him about his vigas he was dropping off. I found out that they came from the nearby local mountains. They came from an area that had gone through a forest fire. As it turns out, the fire went through that area so quick, it just burned the branches and needles, therefore killing the tree but not damaging the tree trunk. So this guy decided to harvest, so to speak, these fine undamaged tree trunks and sell them.
As I stared at these awesome looking vigas, he went on to say that they were known as “standing dead” vigas. In other words all he did was cut them down, take off the bark, cleaned them up a little and what I was looking at was beautiful spruce twisted grain vigas. The biggest advantage to these vigas was the most important to me, the problem that I no longer had to deal with, moisture! These had no moisture, they had been in the forest a few years and were dead before they were cut down. Wow, nice! So from that day forward, he was my “viga man”.
I can honestly say that I never went back to any of my homes and had to re-plaster around another viga again. Ahhh! If you are going to be building a new home, search for this type of viga. Drive around the job sites in your area and you just might find your “Viga Man”.
PS..If your going to have your vigas stick out of the exterior walls of your house, be sure to half wrap them with copper. They last a lot longer and it’s a cool classic look.