We had wooden Marvin double hung tilt-pac windows installed but all without screens. However, there aren't any screen tracks. On the exterior trim, there is a groove/corner on three sides that would fit a screen (~36x54.5) , but it would have to be secured with hardware somehow. And this trim corner does not extend to the bottom sill - rather, the bottom sill is sloped down and smooth. I attached a picture of the lower corner to see where the screen would fit - I am pointing to the relevant corner where I thought I could fit in the screen.
How do I secure a screen to the trim without a screen track and without letting water into the trim/sill? I am worried about screwing things into the wood and letting water in.