I need to see the design but sliding doors going to nowhere make no sense so please post some pics

Along the lines of the attached 2 photos, except ours will be on stilts. I realize about half of the doors will go nowhere, but they're not being used as doors, they're being used as windows (and will have an exterior railing for safety). Decent quality Pella sliding patio doors can be had for ~$330/each at Lowes which is about $8.25/sq ft of window area (72"x80"=40 sq ft) which seems impossible to beat. Also see link for idea of what I'm talking about.

Pella Screened Porch Transformation

It can be a good way to go , it is basically a large sliding window. If you are using stock sizes you are limited on your layout or which way the door slides.

$300 budget and Pella vinyl slider = very low end door.

"Decent quality Pella sliding patio doors"

That is an oxymoron.

Oftentimes in Europe, people install doors with a metal railing that open to a drop-off. I could see doing the same with a sliding door as long as the railing is installed for safety.

Thanks for everyone's feedback so far. Any other recommended (mass produced/non-custom) sliding doors? We are happy tailoring the layout to use stock sizes.

Not familiar with all the box stores stock inventory by brand. Maybe the Anderson 100 series at Home Depot. Guardrail would not be needed in tour pictures since they are on ground level. In my parts it would be needed if the clear opening at the bottom of the door is than 30” to the ground it would not be required.

You have already acknowledged the issue with sliding doors...that one half (or more) of your room will NOT be open to the air, when the doors are open. How many will you need for your room? My home had a screened porch and previous owners installed sliders all around it. I have three double sliders and one triple slider on my 3 season porch (it is build in the corner of my home so I have two “glass” sides.) I find that I usually only open one of the sliders during the summer because the others are blocked by furniture, etc. i never open the triple slider (one fixed pane and two sliders) as they are behind my couch and difficult to access. Another issue...how do you plan (or do you plan) to heat the space for the bridge seasons of spring and fall? Baseboard heat?

PS: I looked and discovered that my sliders were manufactured by KAWNEER North America, which is a commercial glass wall window manufacturer. They are very heavy and have been in our home at least 35 years or more. No issues with them at all!

Thanks, everyone! This is all very helpful.

A follow up question to ptreckel or anyone else who has used a similar structure—does it get very hot in the summer?

We are hoping to have a gable roof with skylights, but have concerns this will become extremely hot if the screens are not open. For reference, we are in Maryland so summers are warm and humid.

Do you recommend some kind of venting?

Thanks again!

Yes...it does get rather hot. I live in NE Ohio. We also have a heavily wooded yard. Despite the shaded yard, we find the sunroom with sliders captures a lot of heat during the day. We have a fan in the room to help with air flow, but tend to use the room mostly at night in the summer when the temperature cools down. At the same time, the room stays quite comfortable well into the fall, and in late spring. I would think about how you can maximize airflow through your sunroom in the summer months, and heat it on the bridge seasons, as needed. (We have an ancient electric baseboard heater on a thermostat for that room and it works fine!)

It will get very hot. We put a sunroom on our house in North Dakota (!!!) and it was uncomfortably hot in the summer and cold in the winter. We regretted building it.

Overhangs, shading , orientation to the sun ,insulation and low-E coatings, can all play a big role in how hot the room will get.