Welcome to the On Site channel’s first Construction Administration Column. David A. Todd, P.E., CPESC, gives his opinion on a common issue with shop drawing approval.

Columnist David A. Todd, P.E., CPESC, has 37 years of experience in the architecture, engineering, and construction (AEC) industry and has performed much construction administration during that time. He will answer questions from our readers or from his own practice and will provide answers based on his understanding of the construction process and administration of the construction contract. The focus will be on the customary duties of the owner, contractor, and design professional as typically described in the contract documents.

Tankless hot water heaters are popular line items on most “green home improvements” lists. Does installing a tankless water heater pay off and, if so, how long does it take to see a return on your investment? That depends on your usage rate and other factors… check out the cost comparisons below.

Most of us take hot water for granted – but we really shouldn’t. According to the U.S. Department of Energy, heating water accounts for 14%–25% of the energy consumed in our homes. If you’re like most people, you have a conventional gas storage water heater that serves your household. When it fails, you’ll likely replace it immediately with another conventional gas storage water heater, because that is the least expensive option and it will quickly mitigate any potential for another cold shower. Iinstead of waiting until your heater breaks, you should plan (now, while the water is hot!) for your water heater’s replacement. We’ll provide basic information about some of your options by taking a look at two types of ENERGY STAR-qualified water heaters: high-efficiency gas storage and whole-home gas tankless. Then, when your water heater fails, you’ll be able to make an educated decision and purchase an energy-efficient replacement.

Building a house over water can be challenging, but floating homes offer a unique way to connect with the landcape.

When Vandeventer + Carlander Architects, LLC were asked to create a Lake Union residence, it was assumed that they would be thinking outside the box, but oddly this time their thinking was required to be within a box. The Lake Union Floating home, located in the heart of downtown Seattle, is not the only residence of its kind, although it is far from being a commonplace building type in the United States. The landscape in the Seattle region is interlaced with waterways and has a long tradition of floating homes that take advantage of the area's gorgeous scenery. However, construction of the Lake Union Floating home presented challenges as well as advantages, and Vandeventer + Carlander Architects’ design navigated the site’s limitations while capturing its many assets.

The ultimate in green design is nature itself. Here, experts explain the concept of biomimicry and give examples of how buildings can take inspiration from natural systems.

If the past 3.8 billion years have taught us anything, it’s that nature knows best. The field of biomimicry is built upon this premise, drawing inspiration from nature’s systems and processes to find solutions for human needs: “innovation inspired by nature.” The implications of biomimicry for the field of architecture could alter the way we design, the materials we choose, and ultimately even the forms of our buildings.

As the holiday season approaches, Rachael, the host of {Re}habitat, has been focusing on eco-friendly alternatives for some of the traditional elements of Christmas.

Living in a small, busy, crazy, constantly evolving, pet-filled apartment has kept me from having the 12’ Douglas Fir of my dreams twinkling in the window. I fear the mess, the drying tree lying out on the curb… and, perhaps most of all, our cats taking it all down in one loud SMASH! In hindsight I feel like I’ve cheated myself out of the full holiday experience by not having a proper Christmas tree.

Need some ideas for gifts this season? The DIYer in your life will love any of these gifts, whether you choose a tool or select a book or music that he/she can enjoy during holiday "downtime.”

Things are beginning to get festive around the international headquarters of Buildipedia. Our managing editor has been wearing the Santa suit since Halloween, of course, but even the video crew is now sporting the green tights and pointy ears of Santa’s helpers. Indeed, representatives of all holiday traditions roam the corridors of the office, going about their important work with a spring in their steps and jolly tunes on their lips. Not to mention the visions of sugar plums dancing in their heads.

You can get the tools you need to complete almost any upcycling, repurposing, or refurbishing project at your local hardware store. Join Rachael, the host of {Re}habitat, as she shares her tips on assembling the simple tools you need to get started.

Your local hardware store has thousands of tools on display, but you only need a few basics in your toolbox. Rachael tells us what to look for when choosing tools, how to keep sustainability in mind, and repurposing tricks of the trade.

A mountain home is gracefully sited to work with the topography and with the needs of its neighbors.

Located downslope from a steep ridgeline in the Blue Ridge Mountains, this month’s featured green home was selected because of its respectful and diligent site placement, conscientious construction process, energy- saving features, water conservation features, and use of regional materials.

The new Barclays Center will not only provide a home for the Brooklyn Nets but will offer the surrounding community a civic space and an architectural  icon.

Not since 1957, when the Dodgers left Brooklyn for Los Angeles, has this popular New York borough been so close to finally having a major league sports team to call its own. Despite significant public opposition, a faltering national economy, a Supreme Court case over eminent domain, and a Frank Gehry design deemed too expensive, the Barclays Center is well underway, with construction due to be completed in September 2012. Designed by SHoP Architects and the sport facility practice at Ellerbe Becket, this voluptuous mass with weathered steel skin will be the $4.9 billion home of the Brooklyn Nets NBA team.

What hand tools do you really need to have around the house? A modest toolbox is enough to get you started for basic home improvement projects.

Every do-it-yourselfer worth his or her salt needs the right tools for the job. For some of us, that means a vast, random collection of obscure and vaguely useful tools like steering wheel pullers and flaring tools for copper tubing. My tool collection includes not only “one use” tools but also several antiques that come from my grandparents and my Dad. Just holding some of those old tools, especially the ones made by hand out of necessity, gives you a whole new perspective on the do-it-yourself mindset. Heck, when was the last time you had to make a tool you needed?

HOK / Vanderweil's retrofit of a government building takes the notion of incorporating nature into design to a whole new level. The facade uses algae-housing tubes to serve multiple functions, including using algae as a fuel source.

When building green, it’s easiest to start from scratch, but the blank slate is an ideal rather than a reality: our stock of existing buildings necessitates energy-efficiency retrofits.

This renovation of a market in Spain preserved more than just a historic building. Restoring the Santa Caterina Market's prominence as a commercial venue has helped to preserve a traditional way of life.

Very few countries are better than Spain at taking the old and transforming it into the new. Currently, this trend has found a new focus – the neighborhood market. Before the chain supermarkets or giant shopping centers began to eat up every available space in town, every neighborhood had its local market. These old (and usually somewhat decrepit) markets have suffered years of neglect and seen hard economic times for private vendors. Now these almost abandoned markets are ripe for the picking, and architects and designers alike are vying for a chance to get their hands on the vast open space that is typical of these buildings.