Pole Barn Trim

   / Pole Barn Trim #1  


Elite Member
Jan 13, 2011
SW Michigan
John Deere 2320
I'm going to replace the siding on my pole barn and have a few decisions to make. It currently has no base trim which is probably part of the reason it's all rusted out at the bottom. I'm going to replace the bottom grade boards and add a base. The supplier I'm looking at offers a rat guard (with an angle trim) and a base trim which is just an angle with a slight drip edge. It's the same trim used as a drip edge over doors and windows. It looks like either would be functionally the same. Is there any advantage to the rat guard other than a little more strength if something was to press down on the horizontal surface?

The other unique area I have is a small area where a swimming pool deck was added after the pole barn was built. The pool deck is 6 inches higher than the pole barn floor. As a result, they just poured concrete against the siding in one area and added a planting area by piling dirt against the siding next to it. Needless to say, there isn't any metal left in this area. My thought is to excavate the soil area down to the pole barn floor, get some tar paper or foam against the poles in this area and pour/grout concrete to make a solid concrete surface, then put a grade board over that. Does that sound like a permanent solution?

Final question - is it still recommended to put tar paper between treated lumber and any metal?

Thanks for any help.
   / Pole Barn Trim #2  
I used rat guard on my building but am not familiar with the angled trim. Rat guard seems to work great as long as your metal is straight along the bottom and lays tight and flush to the grade boards.

We didn't use tar paper, but our metal is coated on the backside with a white finish that's pretty durable. Maybe for galvanized metal its a good idea. Can't see why you'd need it with anything else. Now some people are using tyvek housewrap under the metal as a wind/moisture barrier. Maybe tarpaper is just as useful?
   / Pole Barn Trim #3  
I'm still working on my build about 50% of the medal siding I have used was free. I got it from a friend who puts up pole barns for a living. They are left over sheets from jobs and cover sheets that the factory uses to cover new panels when they ship them. I figured I could paint it all one color when I was done with all the medal work.

I used all kinds of different trim pieces in areas that they were not designed for accept for the bottom base. I did however use several different types.....(different manufacturers offer different styles) but all of them had one thing in common. They all were basically Z channel with a backing of around 3 to 6 inches with a 90 degree turn outward of 11/2 to 2" inch then it turns downward at about 45 degrees for a couple more inches that seals the bottom of the board to keep critters and moisture from getting under the bottom of the siding.

The drip channel doesn't have that 45 degree turn down and where it probably would work ok in a pinch I don't think I would use it for the purpose of base material because it is not as strong and it also would allow moisture to wick in under the medal.

As far as tar paper under the medal at salt treated joints personally I don't see the need. Having said that if you have heat in the building I don't think it would be a bad idea to use tyvec or some other type of house wrap as cockeyedMFer suggested to seal the wall panels from the outside air flows. Most of the guys around here that are putting up pole barns never use anything under the medal and I've looked at some that have been up for years and never saw a problem of panels rusting out where they come in contact with salt treated wood. The panels will rust though....... around the bottoms if they are allowed to come in contact with the ground which is another reason to use the proper base material.

As far as your grade problem nothing is going to work until you get the medal off the ground. You would most likely need to raise the bottom board or add another 2x4 or 2x6 to the top of the original board depending on how low that area is now so that you can raise the base trim to it's proper height that is an inch or so above the ground.

The proper trim pieces are not that expensive if you figure in having to replace your siding sooner than it should.