Archive for 'Windows and Glass'
Posted on 31. May, 2011 by Rebecca Firestone.
Remember last week, when we were talking about glass houses? Well, here’s another Title 24 case study on a 4,500 SF house, also from Swatt|Miers Architects. This house had almost 60% glazing to floor area, much of it custom built on site: 564 square feet of single paned butt glazed corner windows, 540 square feet of frameless glazing, a steel framed window, a 30 foot tall translucent window in a stair tower, 300 square feet of skylights, and a custom built wood screen interspersed with glass panels. That’s almost 2,700 square feet of glass.
And, to make the challenge that much more… piquant… it was in California climate zone 2 (Sonoma – HOT)… AND, they needed to beat California’s Title 24 energy standard by 15% because of local ordinances. It was the combination of all that single glazed area with the climate zone that concerned us the most. But, we had a reputation to maintain, and our motto to designers was, “We’ll never tell you that you have to shrink your windows.”
(Above image courtesy Swatt|Miers Architects.)
Posted on 23. May, 2011 by Rebecca Firestone.
Actually the real question is whether an all-glass pavilion can still comply with the new version of California’s Title 24 energy code. Although Title 24 has been around since the 1970s, it is only now that designers are feeling the pinch. Given the increasing strictness of the energy code, what can an architect do if he (or she) wants to create designs with dramatic glass curtain walls?
The “glass house” shown on the cover image is, of course, Philip Johnson’s famous Modernist masterpiece, also called the Glass House. Even that house could, with the right high-performing window system, comply with Title 24 requirements – I tested it out. But, let’s talk about some more current designs for our case study.
Posted on 26. Apr, 2011 by Rebecca Firestone.
Many architects have yet to realize how much a window’s energy performance can impact their projects, especially under the new Title 24 energy code. Ordinary glass is great at letting in daylight but it’s a terrible insulator. It also does little to block the sun’s heat in the summertime. Windows lose heat through the glass, and they can also leak air around the edges of the frame.
Here are a few analogies to understand the different ways that windows can lose both heating and cooling energy. If you wear a big holey sweater in the wind, it doesn’t keep you very warm. That’s air leakage. Now, imagine just wearing a single sheet of clear plastic on a winter day. It’s a better windbreaker than that holey sweater, but you’ll still feel pretty darn cold. That’s because a thin sheet of plastic, like a single sheet of glass, is a poor insulator. And remember what happens to your car parked in the summer sun? It gets 20 degrees hotter than the outside, or more – if you have black vinyl seats, you’ll scream when you sit on them in your summer shorts. That’s solar heat gain.
Posted on 30. Aug, 2010 by Rebecca Firestone.
Don’t say we didn’t warn you. The new Title 24 is tough! In past articles, we harped on the HERS verifications as a way to earn credits towards Title 24 compliance for those hard-to-pass houses. However, there’s another angle that needs attention: issues for additions, alterations, and remodels.
(Above image shows a whole-house remodel and addition by Mark English Architects. Photo: Michael O’Callahan)
Posted on 06. Aug, 2010 by Rebecca Firestone.
Imagine a home built in the Plains region of the United States that stays warm in the winter without central heating, and cool in the summer without massive air-conditioning. It’s airtight but with an endless supply of fresh air constantly circulating through a filtered, pressure-balanced ventilation system. Every surface is comfortable to the touch, neither too warm nor too cold. Street noise is barely audible through the gasket-sealed, triple-paned windows.
It sounds futuristic, but so-called Passive Houses have been around for at least 15 years, and it’s yet another strategy for saving energy. Unlike a Net Zero Energy home that might rely on “active” power generation, albeit from renewable sources, a Passive House is just that – passively absorbing heat from its surroundings to release it slowly as it is needed. (In hot climates, Passive Houses are designed to recover and store cooler temperatures.)
Posted on 16. Mar, 2010 by Rebecca Firestone.
Green living is sometimes viewed as a sacrificial process whereby one by one, all our pleasures and comforts must be set aside in the name of saving the planet: walking instead of driving, sweeping instead of vacuuming, home cooking instead of take-out, turning the thermostat down in the winter while our hands and feet turn into blocks of ice, low-flow showerheads designed by bald men that take forever to rinse the shampoo out of a long-haired-girl’s mane, limiting one’s diet to only locally available seasonal produce (which could be nothing but cabbages if you live in Chicago), calling three hardware stores to find one that carries low-VOC paint, giving up meat because it takes too much grain to feed a cow, trudging everywhere with a backpack filled with stuff that otherwise we could just keep in the car. In essence, the increased physical hardship comes from asking our own bodies to start doing more of the work. And what’s our reward? A nice warm feeling of altruistic glow, and maybe a slimmer figure.
Efficiency is often seen as achievable only at the cost of comfort – some of us East Coasters remember shivering through the 1970s oil crisis as our dads re-defined 58 degrees during the day as “normal” and turned the thermostat down at night till the pipes froze, and our mothers finally complained. Well, so what? What’s the big deal? We all have to give up something. Well, the problem is that this “fix” didn’t really fix anything. Reducing consumption is not the same thing as having an efficient building, and neither approach presents qualitative factors like comfort or contentment as worthy of consideration.