Asking about local code is tough here. That being said, common sense (and my local code) require railings. We had aluminum balusters which we carried out to the attached deck. So it is not a knee wall - just balusters. The screen overlies the balusters. It is a slight visual block but we used relatively thin black balusters.

Now at the beach - we use stainless steel cable rails which are less visually obtrusive. But if you were really concerned about visuals, you might not be doing a screen.

You will need to do a railing, per Code and also it’s likely required by your homeowner’s insurance, screen panels don’t count as a safety barrier.

One client was very careful to have handrails and railings meet building code for their local area, only to have their homeowner’s insurance company do an inspection and require additional handrails.

What codes require is called a “guard”. It is normally 3 feet tall and a 4” sphere cannot pass through it. It must be able to resist a certain horizontal force. A handrail is required at a stair or ramp where it can also serve as the guard.

There might be glass products to decrease the impact on the view. They will be heavy on the porch and on the wallet.

Our deck was around 36” off the ground and to keep within code of under 30” (without railing) we ended up raising the ground around rhe 160’ deck perimeter to reduce effective height of deck to below 30”. Somewhere in the future we intend to put a 42” glass railing on the deck.

We did posts and hog wire. Didn't block the view but helped with code and safety.

Btw - this porch was 16 feet off the ground.

Tempered glass should have been sufficient to meet the code.

Thanks everyone. First time posting - very nice of you all to reply! Lots of good thoughts.

Our screenporch is elevated as well. I think the porch is about the same size as yours. Safety is important to me since I have young grandkids. We used the same company for the screen porch railing system as the railing on the deck. I think the company was Westbury. Powder coated frame and railing along with the columns that are floor to ceiling. The screen goes from floor to ceiling with a tiny gap. my builder installed this system with a gap at the bottom for water drainage. Our screen is black (I think) and very flexible.. I don’t recall the type of screen. the view to the lake is virtually unchanged with this screen. This is the only picture I have. I can get another pic if you are interested.

Traditional screen porches throughout the south would have 4x4 posts, 2x4 rails (typically @ 36" high) and either 2x2 or 2x4 balusters (looked similar to @ILoveRed's post). All flush to the outside. Screen would be attached over these and then matching width lath strips tacked over the screen. The lath strips were both aesthetic and functional.

We did that on our current house and are doing it on our new house.

Guard rails are now 42"

Locally 36” min is required for guard rails for single family residential, 42” for commercial & multi-family. I really hope it hasn’t changed :/ Will have to check before ordering.

The 36" height for 1 & 2 family dwellings was the standard in the CABO code for almost 30 years before it changed its name to the ICC and wrote the IRC.

Even if your jurisdiction has already adopted the 2018 edition of the IRC, the height of a guard is still 36" where a walking surface is more than 30" above grade and the next edition won't be published until 2021.

Of course, a state or city can amend the IRC or publish its own code so it helps to say where the project is located or to ask the local building official,.