Austin and the Hill Country

This week I was in Austin and the hills west of it. Thursday was the long day: a slope above Lake Travis with a client, a surveyor and the client’s dog, working out where a house could sit. I came home thinking mostly about the roof, which is not where I expected to end up.

Monday: where the Hill Country starts

The Hill Country begins about where the ground stops being able to grow cotton. West of Austin the soil thins to a few inches over limestone, the live oaks take over, and the road starts climbing and dropping in a way that makes every lot a problem of up and down before it is a problem of left and right. On flat ground you draw a plan. Out here you draw a section first.

Tuesday: the roof is the fifth wall

On a hillside your house is seen from above as often as from the street. The neighbor up the hill looks at your roof every day. So we draw the roof as carefully as the front: one long plane, or two, standing seam metal in a color that disappears against the oaks, no vents and no clutter on it. The old ranch houses did this by instinct, a long low roof over a deep porch. The best new houses do it on purpose.

The roof also decides where the water goes, and in the Hill Country the water matters more than anything. A storm here is a wall of rain for forty minutes and then nothing for six weeks. Everything uphill of you drains across your lot, and limestone does not soak it up. So we draw the drainage before the floor plan: a shallow ditch above the house, a dry creek bed that becomes a real channel in a storm, and gutters that go somewhere, usually a tank. The water under these hills is Austin’s drinking water, and the rules about what you can put into the ground are strict and getting stricter.

Wednesday: the stone and the trees

Limestone is the reason this country looks the way it does, and the first thing to understand is that it is not a finish here. It is the ground. Footings sit on it, pools are cut into it, and a crew with a rock saw is on every budget. Build with the stone that came out of the hole and the house looks like it grew there. Truck in a different stone and it never will.

The live oaks are protected in Austin and in most of the hill towns, and they should be. More than that, they are the shade, and the shade is your air conditioning in August. We put the house in the shade that exists rather than the shade we might plant, because a live oak takes sixty years and nobody has them.

One thing to do before you buy a lot out here: have the oaks checked for oak wilt. It is in the Hill Country and it moves tree to tree through the roots. A lot with a sick oak is a different lot.

Thursday: on the slope

The surveyor’s points went into a model of the ground on Wednesday night, and on Thursday we stood on the real slope with the house sketched into the model at full size on a tablet. The client said the model had been right about where the sun came through the oaks at five o’clock. I wrote that down.

Then the creek. You could hear it below the lot, and the sound told us where the floor of the house should be: high enough to see the water, low enough to hear it. No model told us that. We heard it.

Friday: the rules and the tools

Austin is really two cities. Inside the loop it is small lots, tight rules and reviewers who have seen everything. Out by the lakes it is long driveways and homeowners’ associations with design books thicker than the city code. Both have rules about impervious cover, meaning how much of the lot you may roof over and pave, and in the watershed that rule, not the budget, decides the size of the house. Draw the impervious cover first. It is the real limit.

This week a language model read the land code and the watershed rules with us. It found an exception for a kind of permeable paving that none of us remembered, and we checked it against the adopted text, and it was right. It has also been confidently wrong before, so nothing it finds goes on a drawing until a person has read the source. That rule has saved us more than once.

Something I am chewing on

The fight out here is about the hills themselves. Every new house on a ridge is visible to a hundred others, and there is a real push to limit what can go on the ridgelines, how tall and how bright at night. The other side says the land is private and the view is the reason people came. I think both sides are describing a design problem and calling it a political one. A house that sits down into the slope, with a dark roof and the lights kept under the eaves, does not start the argument. We draw for that and let the council do what it will.

Carson Lauderdale, Founder