Concrete Fireplace & Hearth Construction

Concrete Fireplaces and Hearths
Time: 04:46

As all things with a concrete house, you're always contrasting mass and form and trying to obtain a certain lightness, so you don't want everything to be overwrought with the heaviness of concrete. So, primarily, cantilevering the hearth was a very important feature, and then distinguishing it in color so that it wouldn't be so monolithic with the gray concrete. The other thing we tried to do here is develop that angle on the fireplace, so we set the fireplace back deep and that way it shows off the mass of the wall. And even though this is a gas-burning fireplace - it's not a natural wood-burning fireplace - it still has that feeling of the hearth and the feeling of the flame and the feeling of a gathering point, and that was really important.

In the overall spatial design of this house, this is all kind of an open, modern space and the location of the fireplace was important to how the house would feel, of course. This is an informal type of living, and the family wanted the hearth to be near the kitchen area, near where the community is, and that designated its location in this spot.

Wall and ceiling constructionThe ceilings here, as you can see as you look up the three 4-foot lifts, so it's 12 feet, 11 feet 6 inches or so to the ceiling, and then we floated a ceiling here, and you notice that the ceiling doesn't touch the walls. Again, this is to create this sensation of lightness within this rather heavy medium of concrete.

As we had to pour these walls in 4-foot lifts, you can see the line there. That's the first lift. Obviously, we had to make the fireplace and plan for the fireplace, so we put a knockout along the line of the hearth where that green hearth is and there was rebar coming out of the wall already so we already knew that we wanted to cantilever the green hearth. Then we poured that first lift and then those forms were taken and moved up 4 feet and poured again.

The reason why we did this was to keep that smooth finish on the walls. We were able to get into the walls and make sure that the articulation of the surface was really smooth and that everything was okay. If you pour from a very high lift and you're pouring down, a lot of times you can't control what's going on.

Hearth detailsAs with a lot of things in this house, there's a lot of detail that escapes the eye unless you really know that it's there, and this hearth is no exception. It's slightly tapered from the bottom, and it also sort of floats away from the walls. We put a reveal around the edges and kept it away from the walls on the end there, and each one of these little interventions like that requires putting a little knockout in the mold work as they're doing it.

From countertops to floors, fireplaces, walls, you can see that anything is possible with concrete. You can start small and dream big.