A little revisit to a recent concrete countertop project helps to demonstrate the rationale and inspiration behind some of the design decisions that we make when contemplating an upcoming project.  Always a collaboration, of course, between artisan and client – the concrete results incorporate the designer, the owners and their respective environment, be it a home or business.

In this particular case, we knew that the kitchen remodel included a multi-colored slate tile backsplash and the existing natural cherry custom cabinetry. The situation required a little thought about the proper means of tying this together. we opted for a subtle gray/green sage base color for the countertop, with some black sand (recycled coal slag!) added for texture, and a series of one inch square glass mosaic tiles, backpainted in tones to coordinate with the slate’s amazing range of color. These were arranged in a fourquare pattern and embedded at three different locations in the tops. Seen in context, it all makes perfect sense. And that’s why we love what we do – reasons to be cheerful.

The concrete countertop we cast in our “Terra” shade was installed last week in its final home, atop a natural birch cabinet vanity. The colors worked together as intended, with the warm orangey wood and the tan/beige marble baseboard tile bringing out the concrete base color as well as the circular ”Caramel” inserts. A little sprinkle of amber glass echoes the sink orb and contemporary faucet geometry, and lends a little motion to the vignette.  All in all, a fun project! The kitchen will be next…

We are wrapping up an interesting little project casting fifteen concrete windowsills in a total of three different conformations. They will be installed as  interior finished surfaces in an area architect’s personal home across the river in New Hampshire. The residence is a beautiful composite of vernacular barn, mill, and house styles found here in northern New England. The window jambs in the brick bearing walls are deeply inset; these sill units will provide a nice place for houseplants, the family cat, or just dappled sunlight to reside and will provide a bit of thermal mass.

They are three inches thick at their deepest point and have a nice quarter-round molded detail with returned ends at the underside of the apron/stool intersection. The sills are integrally colored with a light terra-cotta tint and all exposed surfaces sealed for easy maintenance; the top is polished and filled, while the front (non-wearing face) is left with the casting marks and bugholes intact, for honesty in materials.

A basic and serious situation

The topic of concrete warp or curl came up on a peer forum recently, so I thought I might share it on the blog. Many people may be unaware that concrete can warp, big-time, and it is not a pretty sight when you have labored over a given casting and then it goes bonkers on you right when victory seemed to be within your grasp. And so:

Original post by RM:  Hey I was just wondering if anyone has had a C-top warp. I haven’t seen or read about it…..but if it does happen than it will happen to me.

My reply:  Certainly – it has happened to all of us many times. It’s one of those things that doesn’t get a lot of press (surprised you haven’t run across it already though), but is always part of the equation as soon as you get into casting. It is a crucial part of the learning curve. Many factors are involved (a partial list): mix design, w/c ratio, post-casting protocol, curing, ambient conditions, scheduling, installation location, sealer type, overall dimensions of the piece, etc.
A very involved topic – one of those for which you get a “seat of the pants feeling” for, after awhile and it becomes second nature, to be aware of all these potential effects on your “babies”. Prevention is the main action but mitigation is always possible too. Nowadays, on the rare occasion when I do get a bit of warping or curling sneaking up on me despite what I thought were adequate precautions( I have even heard it referred to as “potato chipping” which is apt), I don’t freak out because I know I can reverse it quite easily as long as it is caught early. All about being aware and being “one with the concrete”. You have to live your material – think like a slab!

PS I will try to elaborate on causes, prevention, and redemption in another post, another day. Meanwhile, back to the mixers!

Look out below!

At Concrete Detail, we take great care to “do it right the first time”. That’s just one of the reasons we chose that particular name  for the enterprise: to take what is often a common, utilitarian material and refine it into a beautiful, precisely engineered manifestation of functional art for a client’s  home or business. It’s truly “all in the details” when it comes to concrete countertops.

But even the best laid plans go awry occasionally (actually,  rarely!) and something comes out of the form which is not quite up to our standards. It’s that moment of unveiling the day after the pour, when you are finally able to see the end result for which you strove  in the days leading up the actual casting. The culmination of templating, formulating, forming, mixing, cleaning, etc. is revealed when the forms are stripped and the piece flipped over: daylight breaks on the new surface and the alchemy of concrete is manifest. Usually a wonderful moment of revelation, but sometimes things take a turn.

Then it’s  ”Sigh…mutter mutter @%!# mutter” and then,”OK – this is one for the books -please make a note - and off to the docks!” And we haul it out to the  loading docks just outside our studio doors, check for for small children and slow dogs, and at the count of three – ONE TWO THREE PUSH! Crash. It’s somewhat cathartic.

So, how do you make a concrete countertop? A little more process discussion…

After a template is made by recreating the exact  layout and dimensions of the cabinetry where the finished tops will be installed (using thin strips of lauan plywood and hot melt glue), the transferred shape is duplicated in the shop in the form-building process. Outside dimensions are matched with edge forms on a base sheet; cutouts for appliances or fixtures are located precisely and blocked out (concrete is unforgiving after the fact).

The completed form is moved to the casting table, the concrete is batched and mixed to a very strict formula and then placed carefully so nothing is disturbed. Vibration is applied to consolidate the fluid mix and drive air bubbles to the surface, strengthening and densifying the material. Then the wet slab is lightly floated with a trowel to smooth the under-surface (since this is reverse casting) and wrapped up to retain moisture overnight.

The pictures accompanying this post, from a current project, show a freestanding island cabinet in the cabinetmaker’s shop while being templated (no overhang on this piece) and the resultant form (with cooktop blockout) immediately after placing and vibrating the piece on the casting table in our own shop.

We have finished the fabrication of our latest concrete countertop project, a vanity top for a home in the Upper Valley in New Hampshire. An earlier post dealt with the design sketch whch begins this process; there are many factors which are taken into account when a new element is conceived. The client’s preferences and inclinations, the immediate location, the nearby surroundings, the use patterns, and the concrete artist’s vision are among them.

This concrete countertop will be installed in a somewhat typical full bathroom near the public living area of the home. The walls are white, the floors are a very pale shell pink ceramic tile, the fixtures are white , and there is a thin strip of marble tile as a baseboard detail beginning to introduce a bit of color to the room. The dominating feature is the natural birch vanity cabinet which has large round wooden pulls. The new sink was to be a circular white porcelain bowl and the faucet a cylindrical, sleek chrome contemporary style (matching the towel bar). These are the influences from which we drew to create an appropriate addition to the melange.

The result – a long sleek top in “Terra” (an earthy, sandy tone which picks up the floor tile and baseboard) with the sink set obliquely at the right end. A small bow in front of the sink swells from the five and a half foot long edge, with a set back hand-drawn line following its delineation. Several varying circular insets of “Caramel” concrete pick up the birch cabinet’s shades, while a sprinkle of recycled amber bottle glass shadows the sink and faucet. The backsplash is a narrow 3 inches tall, in “Terra” again, with a pair of  inch-square glass mosiac tile inset at the centered seam, referring to the white porcelain bowl. The entire top is lightly ground to show the crushed glass and some fine aggregate, giving it a warm subtle texture. Install is coming right up – and the kitchen is next!