What is the best way to determine how big or small a building or tree should be?
I don't my dio too look out of scale.

Thanks
DA

In 1/35 scale, that means that one unit of measure is equal to 35 units of measure on the real thing. If you built a one foot tree for your model, it would scale up to a 35 foot tree in real life. It also converts to metric for everyone besides us Americans. One centimeter on your model is equal to 35 centimeters in real life. I hope this answered your question and did not confuse you.

Patrick

Patrick is 100% correct in his explanation.

But working in the correct scale can be very difficult.
For example, if you would plan to put a building of 3 high in your dio then that building (in real scale) would over dominate the vehicles and figures in your scene.
So sometimes it is necessary to cheat a bit.

Sheperd Paine uses this trick all the time.
Lets go back to the 3 story building.

Ground level should be build right on scale
1 floor 1/3 less in scale height then ground level
2 floor 1/3 less in scale height then 1 floor.

I hope you understand what I mean #:-)

For trees, there are big and small trees, so don't worry to much about it, by using your vehicles and figures try to determine a size that looks good but dos not overpower (trial and error), vary the sizes a bit and it will look fine

Both pervious posts are right on.

One thing I do when building diorama (especially from scratch) - I go measure the real thing and convert.

If I need a winodw, I measure a real window to get reference sizes. If I need a tree, I go outside and mesure the width of the tree.

Check out this thread for some more help.
https://armorama.kitmaker.net/forums/2890&page=1

They are all completely right. BTW, if you just happened to have a slight miscalculations in your dio items, just move it away a few distance from the model.

All comments above are ok.
I do like this but also I use a stand-up figure for measuring almost everything and to see how will look