I Just abandoned my town because they were not repairing anything. I ran with 20 Laborers and 15 builders for 4 in game years and 2 Barns, The Market!, 4 of my foundries 7 grain storage and 21 houses all went abandoned/condemned
They didn’t repair ANYTHING! Tear it down and rebuild? sure ok but then I have to fully upgrade it again wtf. It was weird also because everything was ok then they all popped up and thats when I pulled miners out of the coal mines and sand pits to work as laborers and builders. didn’t help …
v0.7.5d should have fixed this, give it a try and see.
I actually just tested this and it seems builders will prioritize new construction and upgrades over building upkeep, regardless of how low the buildings get, so when you start seeing bars above them showing they are getting low, go to any building you are working on and turn off construction for it. The builders will then have free time to move on to building and fence maintenance. The first wooden fences you get seem to take a beating by either the weather or wildlife as the builders will even try to go do upkeep on them, so as soon as you can maybe upgrade any farm fence at least once so all those fences don’t need constant mending.
We probably could do with additional management settings, things like this (setting builder priority) as well as being able to set arborists to cull any trees over a certain maturity. And the word cull should have a more widespread use and apply to other trees rather than use “harvest” to mean chop down. I was confused at first with for example hawthorn not knowing if harvest would mean pick the fruit or remove the bush. Definitely don’t use “harvest” for chopping down trees 
The difference here with fruit trees is that Harvesting is done by laborers and when you use the harvest select tool, with trees checked, it will still exclude the fruit trees for good reason. Designating a tree to be culled is an action performed by the arborist so it is something he can work on during any off season. I found that the date frame listed on the seed types isn’t exactly accurate. The apple tree’s for instance, say September - October but after the first week of July, the Arborist can begin harvesting from them. This knowledge of when things can be harvested is important if you are juggling man power around to keep them busy.
So far, nothing being built. 53 Laborers (of population 208) 0/10 on builders… materials are on hand but nothing is getting repaired.