Separation Between Slab on Grade Garage and Large Poplar

[calgaryacreage]

Hi there - this forum is great. I've searched the threads to see if this is covered, but can't quite find the answer.

We are on an acreage and want to put up a shop/garage. No footings are required, but we will put a slab on grade for it.

The issue is that the ideal spot for the garage (from a functional perspective) is very close to a large poplar tree (I'd guess 30+ years old). Fitting this garage onto my property is a bit of a jigsaw puzzle and I'd like to cozy it up as close to the tree as is possible....but the last thing I want to do is kill the tree.

Is their a rule of thumb for how close I can get? Any suggestions/recommendations?

Thanks!

 

[ATH]

Rough rule of thumb:
Measure the circumference of the the tree at chest height. Then measure that distance away from the trunk. If you cut roots within that zone, they are likely anchoring roots. If you cut those, you are endangering the stability of the tree. Next, how much of the root system will the slab cover? Beyond the slab, protect the rest of the root system from construction traffic (compaction) and absolutely don't let them pile soil over the tree's roots.

Now that we've protected the tree, the question becomes how much of a problem will that tree be for the garage in the long-term. If you can stay outside of that, make sure you have a good base, and an adequately thick slab. Tree roots take a lot of blame for poorly laid concrete. You might consider putting a root barrier along the slab. Here is one example: https://www.deeproot.com/products/root-barrier/