Within minutes of walking into Down House, the bar-restaurant-living room concept on Yale Street in The Heights, I told my girlfriend “This place is so cool. I could probably stay here for hours.” And that’s exactly what I proceeded to do.

I’d arrived a bit after 7 pm, intent on having dinner and drinks, but hadn’t planned on a four-hour outing. At Down House, however, the vibe is so cool and laid back, you can’t help but want to kick back and just hang.

On first impression, Down House reminded me of one of those bar/restaurants in D.C’s Georgetown area. With blue-painted brick walls, scientific and plant motifs, and even a bike hanging on the wall, the place named after Charles Darwin’s home felt like it had been and would be there for years.

There’s no proscribed rule against lounging for hours on end either. The 2,800-square-foot space is meant to be inhabited. Want to have lunch, then work on your laptop until dinner time comes around? No problem. The French press coffee is bottomless, there’s free WiFi for all and the servers are as laissez-faire as you need to them to be. You’re welcome to relax on one of the comfortable-looking leathery couches. Want to grab a bite or have a leisurely drink? There are smaller, marble-topped tables for people flying solo, and larger tables in the middle of the room to accommodate groups.

Also, the fact that Down House is open 7 am to 2 am means that it’s there to meet customers’ needs at pretty much any time of day, be it coffee, breakfast, lunch, snacks, cocktails, beer, wine, or dinner. If anything, Down House is ambitious.

On the night I was there, the 20s- through 40s-something clientele ran the gamut from couples, to groups of friends, to young families with small children. You could definitely people-watch, too, and I found myself admiring the kind of Justin Timberlake, William Rast-type swankily clad male servers, each sporting a tie and button-up shirt with rolled-up sleeves. Our server was wearing a vest, which imparted a sort of speakeasy, Prohibition-era look to his outfit, and I couldn’t help but appreciate his style. “Is that the uniform here?” I asked. “We have sort of a code, yes, but we can express it how we want,” he replied.

My girlfriend and I each started off with cocktails before ordering something to snack on. My Queen Bee cocktail, a sparkling wine cocktail made with crème de Violette, gin, lavender tincture and lemon, was served in a Champagne glass with a small floating flower as garnish. It was light and refreshing, with a bit of fizz to make it interesting, and enough liquor in it for me to get a bit of a buzz on an empty stomach. (Yes, I am a lightweight.) My friend ordered a delicious Normandy Tart cocktail from their seasonal menu, a fun, apple pie-inspired cocktail served in a brandy glass, with a thick foamy top and spiced sugar rim.

Food-wise, the deconstructed deviled eggs three ways (traditional, Indonesian and Provençal-style) were fun bar bites to try. The poutine, a Canadian dish that is basically a large plate of French fries topped with gravy and cheese, was a bit heavy for pre-dinner nibbles, but I imagine it would have been stupendous as a late-night hangover helper.

For greens, we tried a kale salad topped with crisp croutons and a delicious green bean salad with lardon and a poached egg. The green bean dish was a very tasty riff on a classic French frisee au lardon salad.

The highlight that night was the Longhorn Burger, a $12 Sabra Ranch (grass-fed beef) burger that you could order with a choice of bacon and a fried egg for a small supplement. I ordered the works, medium rare, and it was a thing of beauty, from the Slow Dough challah bun, to the huge, dripping-in-juices meat patty, to crisp Niman Ranch bacon, to the glorious runny egg yolk that covered everything in every bite.

We ended the night with a just-out-of-the-oven, buttery-crisp croissant bread pudding and a smooth, aromatic Amaretto as an after-dinner digestive. By this time, it was well after 11 pm, the lights had been dimmed, the music had mellowed down and had it not been for my food and alcohol-induced drowsiness, I have no doubt that I could have stayed until the very end. There’s always next time.

DOWN HOUSE, 1801 Yale at 18^th, 713-864-3696, downhousehouston.com