What makes the eight-classroom addition for Langford Elementary a "Green School?" Does it make any difference?
Our goal for Langford, from the very beginning, was to make improvements on anything that consumed resources over the life of the building. The whole team, the District's project manager and their energy consultants, our engineering consultants, and the contractor thoroughly embraced this challenge. We all agreed to look with fresh eyes at all aspects of the project and to find innovative ways to meet this ambitious goal.
There wasn't any one thing that made this a green school. The solutions we devised consisted of a number of best practices that are increasingly available. There were also areas where we innovated, including ways to double-use spaces. We developed signage to show teachers and students how to conserve as they use the building.
We did a lot to save energy with the air-conditioning. A high efficiency system supplies individual units that have separate controls in each classroom. The roof is designed to minimize heat gain, with R-30 insulation and a reflective surface. We designed most of the windows to face north and south. The hottest sun comes from the east and west, so those windows are shaded with deep awnings. The wall insulation completely covers the studs, so they don't conduct heat into the building.
To conserve water, the toilets are "double-flush." This means lower use of water to flush liquids; a fuller flush for solids. To minimize water in landscape irrigation, we specified xeriscaping, or plants that grow with little or no extra watering. A rainwater collection tank gathers runoff from the roof to use when the plants do need watering.
Daylight cuts down on the need for lights. A skylight in the gathering spaces uses a translucent insulated panel. This system diffuses the light so the hallways lights are almost never needed. In the classrooms, windows let light in from both the outside, and from the sky-lit gathering space. The switches for each classroom allow the teachers to turn off each row of lights so they only illuminate the areas that are dark.
We developed informative signs to remind teachers and students that their behavior also determines how much energy is used. We had heard that some teachers in other "green schools" had been leaving the lights on, or complaining when a photocell automatically turned them off. The simple diagram above each bank of switches seems to be working.
Hallways, in most schools, are empty places during most of the school day. Architects usually think of them only as connectors between classrooms. When we designed the front four classrooms, we turned them a slight angle. That made the hallways wider at the ends, so they can function as gathering spaces. Teachers are using these areas as break out spaces for small groups or individual instruction. Without changing the normal program, we still were able to add new functionality by making the better use of the circulation space.
So, has any of this made a difference? Is there any real benefit for all the effort? In order to be considered for the City of Austin Green Building Program, the school's actual performance was evaluated after a number of months in use. The results show a big impact and have earned the project a 4-star rating. The school has now been in use for a full year, so we were able to collect even more relevant data. Langford used almost 20% less water the typical school. The energy savings were even more substantial. The building saved nearly ¼ of the energy that Austin Energy normally estimates for a school.
The obvious long-term benefit is lower operating cost. Austin's school districts are anticipating increased costs for energy and water in the years ahead. They are emphasizing extra investment in sustainable building, though we were able to implement the program without an increase in the budget.
Other benefits are also going to be studied. The day-lighting has created a warm and friendly learning environment. There is an interest in monitoring student performance data in schools of this kind. Early studies have begun to document the connection between a day-lit learning environment and alert, successful students.
Here is the latest video blog post i did with Matt Risinger. This time we are discussing hot water systems for residential construction. In this post we talk about using an AO Smith Vertex tank heater versus a tankless water heater and using a demand pump and a trunk line system for hot water delivery.
Here is a video Matt Risinger and I shot for his video blog on Residential Green Building. In this video we are looking at using as separate dehumidification unit to help control humidity and thus use the house AC units more efficiently.
Here is a link to his blog. He has lots of really useful information here--and if you look carefully, you can see more of me as well!
Islesford, Maine on Little Cranberry Island is a beautiful place, but has very few frills. For the year-round residents and the summer regulars who join them, the essentials are all that count. There's the Neighborhood House that shares space with a public library and a one-room post-office that doubles as the island store. The one restaurant is seasonal, yet attracts a steady crowd of diners, many of whom make this a regular stop on the Maine coast.
There are two churches on the island and both of them were crafted with the same no-frills approach. The Islesford Congregational Church was built in 1898 in the shingle-style mode, typical of the area. The large, unadorned gables and upright steeple form a simple and distinctive profile, just visible from the docks down the hill. The front façade has three main windows, one of which has ornate stained glass.
The church's main open space serves the larger summer congregation. The interior remains unfinished, and unpainted; simply the exposed framing, roof and walls. A bit of flare with the truss-work adds visual interest. There is a modest organ and a carved wooden pulpit. A smaller chapel serves the winter congregation. This space has a finished interior, which I assume is heated and insulated.
Our Lady Star of the Sea is the Catholic chapel, located further inland in a clearing of trees. Regular mass is held only in July and August. The structure appears to be about 30 or 40 years old. A basic rectangle shape covered in shingles, it has the utilitarian look of the old boathouses near the shoreline.
Like the Congregational Church, it also has unfinished interior walls. The wood, however, is painted a monotone grey. Pronounced down-lighting focuses attention on the modern altar. The basics here also include a tabernacle in one corner behind the altar, and a statue of the Virgin Mary in the other. Darkly-tinted stained glass windows make the small interior feel even more close and intimate.
We spent a delightful week on the island this summer. As I contemplated the basic image presented by both these buildings, an old van added, literally, another note to consider. The cars on the island are also pretty basic, just a handful of trucks for the lobstermen, and a few cars. This old van had stenciled lettering on the rear door, "Caution Pastor, stay back 50 feet."
Given that is is August and Austin has hit 107 the last couple of days (not to mention over 100 for the past 19 days), I am not sure it will ever be used, but the new house has a couple of interesting features to help coax in a nice cool breeze. They probably work now, but that would basically turn the house into a convection oven...
View of the house from the Southeast -- the direction of the prevailing breeze.
The first green building feature is the mass of the house, which is designed for breezes. The winds predominantly come from the SE here, and fortunately the lot faces roughly that direction. We extended the garage portion of the house out to help capture and channel the wind. Next, we have large porches on this facade, which not only shade the windows but allow for a cooler air mass for the air coming in the windows. The old Southern mansions used to hang ferns on the front edge of the porch to also help cool the air. We will try this when we can hang a pot and not have it scorched within minutes.
Pop-up Dormer with operating awning windows at back side of house allows north light and creates breeze with the chimney effect.
The second green feature is to have a narrow open house with clear air flows to allow the breeze to easily move through the house. We added a pop-up dormer on the back side, which in addition to allowing north light into the house, allows air to move up and out of the house with the chimney effect.
The third feature is the addition of lots of operable windows. We have this in the double-hung Marvin Integrity windows we used. As an added bonus, the double-hung nature of the windows allows us to shape how the air flow through the house. Since the front door is a big part of the facade, we wanted to make sure we could get air in through this area as well. However, given the insects of Texas (yes, they too are bigger in Texas), we needed to have screens. I have never been a big fan of screen doors -- I hate opening two doors. To solve this problem, we had a custom door made that has operable sidelights with screens. Now, when the weather is right, we can open the sidelights to get the air and have screens without having a screen door.
Front Door has operable sidelights with screen, to allow breezes while avoiding a screen door.
There are lots of interesting ways to help coax the breeze through houses -- just look at the pre-air conditioned houses. But since most of them are structural, they should be addressed at the outset of the design process, so make sure you are talking through these issues with your architect and builder as early as possible.