Thornton Concrete Finishes

Somewhere near the end of an estimate, usually while we're rolling up the tape, somebody asks what finish they want. The conversation lasts about ninety seconds. Then you live with the answer for thirty years, through every wheelbarrow, every dog, every February morning with a shovel in your hand.

We'd rather spend ten minutes on it. Not because one texture is better than another, but because the right one depends entirely on what crosses that slab on a Tuesday. A dog run, a garage apron, a patio where people go barefoot, and a walk on the shaded north side of the house all want different things, and one property often needs three of them.

What actually crosses your slab

Start with the traffic. A driveway apron takes tires, a plow blade, and the worst of whatever the street was treated with. A back patio takes chair legs dragging, a grill cart, bare feet in July, and a hose in September. A dog run takes claws and has to rinse clean in two minutes. A shop apron takes a tractor tire and a floor jack.

Now think about the two chores you'll actually do out there: clearing snow and cleaning. A heavy broom sheds snow well but holds grit down in the grooves. A fine broom clears faster under a shovel and still gives footing. A hard steel trowel finish, which is lovely indoors, is a skating rink outside and we won't put it on an exterior walk. Float finish sits between the two and it's the quiet workhorse nobody asks for by name.

Where one finish should hand off to another

How to pick, in the order the questions matter

• Who walks on it barefoot, and how often
• Whether a shovel or a plow blade crosses it every winter
• How much shade it gets, since shade decides how long ice sits
• Whether furniture legs and carts have to slide across it
• How it gets cleaned, and whether a hose has to move debris off it
• Whether it faces the street, which is an appearance question rather than a use one
• Whether it will be sealed, because a film sealer changes the grip of any texture
• What the rest of the property already has, so the new work reads as part of the house

What Front Range weather does to a finish

Finishing is timing work, and the weather here keeps moving the timing. On a hot, dry, windy afternoon a slab can go from too wet to too stiff in the time it takes to walk its length, which is why we start early in July and August and why you'll see us keeping the surface damp. On a cool October morning the bleed water takes hours to leave, and troweling into bleed water is exactly how you get a surface that flakes off three years later.

Rain during finishing is the real damage. Extra water beaten into the top layer leaves a weak, dusty skin, and it shows up as scaling long after everybody has forgotten it rained that day. We watch the afternoon build over the foothills all summer and we'll reschedule rather than gamble your slab on a radar guess.

Best months here are late April through mid October, with September the one we'd choose. Winter pours get warm water, a chloride-free accelerator, and blankets, and the texture gets simplified to a broom, because you can't stamp or wash a slab that has to be covered right away. Never on frozen ground, in any month.