Thoughts on creative uses for an 8x8 deck cutout?

I had a similar void when we pulled out an old Jacuzzi at our place in Eau Claire. We ended up splitting the 8x8 space into two zones. We framed out a 4x8 section for heavy-duty waterproof storage. 22 inches is the sweet spot for storing those thick Sunbrella cushions and bulky winter covers that ussually clutter up the garage. We used heavy-duty bins and they fit perfectly under a flush-mounted hatch made of capped composite boards.

For the other half, we built a raised planter bed. Since you’re worried about maintanence, I’d suggest lining it and doing a self-watering setup for hardy perennials or even just some decorative river rock with a few potted shrubs. It breaks up the flat look of the deck without the fire risk. We used NewTechWood for the trim beacuse it handles the ice and salt much better than the old cedar ever did. It’s been three winters now and the drainage hasn't been an issue since it sits right on that slab.

I’d steer clear of using that pit for storage. In our climate, those deep voids underneath a deck become a breeding ground for spiders and trapped moisture, no matter how "waterproof" your bins are. Instead, we handled a similar recessed area by turning it into a sunken container garden using galvanized stock tanks from Behlen Country. Since you have that concrete slab, drainage is already handled and you won't have to worry about soil rotting your joists.

We dropped two 2x2x6 tanks in there and filled the surrounding gaps with oversized river stones. The 22-inch depth is acutally perfect because the deck itself acts as a windbreak, protecting more sensitive herbs or native perennials from those brutal Wisconsin gusts. It adds a ton of texture to the space without the constant upkeep of wood or the boredom of flat composite boards. If you're still worried about fire safety, we put a small propane-fueled fire table right in the center of the stones. It keeps the heat contained and stays far enought away from the house siding to satisfy my anxiety. It feels like a custom feature rather than just a patched-over hole, and you'll never have to pick up a sander or a stain brush for that section again.

Ever thougt about a sunken lounge? 22 inches is basially the perfect height for bench seating. I'd frame out the perimeter with some composite benches and leave the center open for a weather-proof rug and a low coffee table. It's a killer spot for drinks and it'll actually block the wind, which is a lifesaver in Wisconsin. Since you're on a slab, you don't have to worry about the weight of a bunch of people hanging out down there. It's way cooler than a flat patch and won't give you the headaches a planter woud.

Since you've got that solid concrete base, you shold definitely turn it into a built-in outdoor kitchen. I'd drop in some Trex Outdoor Kitchens cabinets—they’re basicly indestructible powder-coated stainless steel that won't warp or rust in the snow. You coud use that 22-inch depth for a pull-out trash bin or even a small beverage cooler. It solves your maintenance headache and looks way more high-end than just patching more decking. Have you looked at thier Sunset Silver finish? It whould look sharp against the Wisconsin gray sky and it's basically zero upkeep compared to cedar.

That sunken lounge idea sounds cozy on paper, but have you ruled out the drainage logistics during a Wisconsin spring melt? If that 8x8 pit fills with slush or heavy rain, you're basically looking at a temporary swimming pool right against your house foundation. Even with a slab, that water has to go somewhere fast. Also, 22 inches is pretty deep for seating without a dedicated drainage pump—have you checked if the slab is actualy pitched away from the house? I'd be worried you're just trading hot tub maintenance for a perpetual mildew battle.