Just wrapped up that 109ft walkway build — a few takeaways

I ran into a similar situation with an 80-foot boardwalk using Azek Vintage boards a few years back. Working around those oak trees is the hardest part because you have to leave enough of a gap for growth without making it look like a trip hazard. I tried those tight miters like you did, but I found that the expansion and contraction in our climate made them open up after the first winter. I eventually swapped to a more rounded scribe cut using a jigsaw, which gave the boards more room to breathe.

Using composite for the framing is a smart move for something sitting low in the woods. I used pressure-treated ground contact lumber for mine and I already see some moss starting on the joists where the airflow is tight. Managing a crew at 23 is no joke either. I was still just a helper at that age, so getting a hundred-plus feet done in ten days with two guys is a solid pace. Just keep an eye on those miter joints when the temperature swings hit.

I went a different route when I built a similar 120-foot ramp through a cedar grove. Instead of the Owens Corning composite framing, I stuck with pressure-treated 2x8s but wrapped them in Joist Gasket tape. I worry about the flex in composite framing over long spans, especially with three people and heavy equipment moving over it. Did you notice any bounce in those 109 feet?

On the tree gaps, I actually stopped trying to do the mitered borders entirely. I started using flexible PVC trim boards painted to match the decking. It lets the tree sway during high winds without risking a board popping loose or catching a toe. I found that no matter how tight I got those cuts, a heavy storm whould shift the trunk just enough to ruin the alignment. It’s a lot of work to maintain that look over five or ten years when the roots start lifting.

I'm just starting to look into building a small porch and honestly didn't even know composite framing was a thing. Is it way more expensive than regular wood? Also, how do you figure out how much space to leave for a tree? I'd be so scared of the tree growing and just snapping the boards. Does the tree species matter for that? Sorry if these are basic questions, I'm still learning the ropes.

Have you ruled out the possibility of the footings settling under that 109-foot run? Ten days for three people to do the demo, footings, framing, and those custom tree miters sounds pretty fast for a wooded lot. I'd be worried the holes weren't deep enought or the concrete didn't have time to fully set before you loaded it up with all that composite weight.

Also, did you account for the root lift? If you're tight to the trunk with those mitered borders, even a little bit of growth or a heavy wind storm shifting the root plate coud heave that entire section of the walkway.

You’d better hope you used high-quality fasteners like the Simpson SDWS or GRK structural screws for that OC frame. Standard wood screws will shear right off when that composite starts moving. 109 feet is a massive run for thermal expansion—if you didn't leave at least a 3/16 gap at the butt joints or use somthing like the CAMO Edge clips, you’re looking at some serious buckling once the sun hits it. Did you stagger the joints or just run them wild? I’ve seen 100-footers turn into a roller coaster beacuse the builder ignored the manufacturer’s temp-at-install charts. That glass-reinforced framing is stiff, but the boards themselves still want to grow.