greenhouse DIY Greenhouse With Shade Clothe Help

Most people go for around 30 percent shade it seems around here.

I think choosing any cloth lower than 50% will be fine. I use a weed barrier as shade cloth and it works great
I have not used a shade cloth since i started using the poly from this gentleman. I have a 16x22 hoop house and have consistently grown 300-350# of Tomatoes and 75-100# of misc peppers with no sun damage.   This year i never ran the fan even though we had some VERY hot temps.   Didn't seem to bother......