The 16' span is how the house is constructed and based on how quickly I get up to speed on my masonry skills I may well add a foundation support on some of the future ones.
I have considered felling some trees to cut and use for the columns and may well do that. I'm kinda/sorta intimidated when I walk up to one with the chain saw and have only cut down smaller trees to date. Most of the trees are around 100' tall and I can't reach around them. On the other hand I do have a couple light poles on the property which I may take down and use. They are closer to being the correct diameter.
I do plan on selling some of the timber to raise money to put into the house
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