This is our annual issue dedicated to sustainable residential design. When covering this topic, we're inevitably pushed into making a devil's bargain. We won't sacrifice our notion of good design just to show something “green.” We'll always select a house that's more beautiful over one that's more sustainable. And we'll feature an architect who's more talented over one who's more dedicated to the cause if the aesthetics suffer.

In the past, we've justified this choice by reasoning that the beautiful house may prove more sustainable in the long run because people will love it, care for it, and preserve it. This is a lovely syllogism for the enduring value of architecture, but lately it's troubled me. I've been wondering what our maximum budget is for buying into this argument.

Perhaps it's $11 million? That's the conservative quote for shoring up Frank Lloyd Wright's 70-year-old sagging masterpiece, Fallingwater. Certainly, that amount of money could do a great deal of good directed elsewhere. But then we'd lose what many people think is America's best work of residential architecture—maybe even its greatest building, period. How do we tally what this house has taught us about site-sensitive design, about the weaving of structure and nature so that both are ennobled? By that measure, maybe $11 million is a bargain.

Well, then, what is our top threshold? How about $3 billion? That's the projected cost of the “Moses” floodgates designed to protect Venice from ruinous storm surges. The floating city is one of the architectural marvels of the world, and it's irreplaceable at 100 times the price. Yet it's also as fragile as a Fabergé egg, and $3 billion may just buy it more time while endangering the equally vulnerable ecosystem of its lagoon. After much deliberation, construction is under way. Like star-crossed lovers, we're determined to savor the borrowed moments of this doomed relationship.

Which leads us to our Venice, the city of New Orleans. The Mortgage Bankers Association thinks it'll cost at least $8 billion to repair the 95,000 single-family houses damaged by Hurricane Katrina. Just the houses—not any other buildings, nor the battered infrastructure. Should we rebuild New Orleans when the city is not, by many accounts, sustainable? And yet, how can we not rebuild it? It's undeniably a national treasure.

How much are we willing to invest to preserve something beautiful, even when good sense tells us our money is better spent otherwise? Can it really be true that something of enduring delight is more sustainable than something more earnestly practical? I suspect the reality is less romantic than we'd like to think. A building or place that's low-maintenance, functional, flexible, and blandly pleasant to look at may prove the most useful, sustainable, and lasting in the long run.

But where's the delight in that? Such a building won't make it into the pages of this magazine. Because we love beautiful architecture here. It's first and foremost what we are about. And when we consider green design, as we should and will do more often, we won't grade aesthetics on a curve. We're eagerly waiting for architects to make the practical more beautiful and the beautiful more practical. Then we'll have no devil's bargain to make.

Comments? Call: 202.736. 3312; write: S. Claire Conroy, residential architect, One Thomas Circle, N.W., Suite 600, Washington, D.C. 20005; or e-mail: cconroy@hanleywood.com.