Designing Your Perfect Houseenergy efficiency

Do You Have Hot and Cold Bedrooms?

Bill — Mon, 12 Apr 2010 13:04:31 +0000

Are some of your bedrooms too hot or too cold? This is a common problem in new homes. Often the master bedroom will be fine, but the other rooms get too cold or too hot during the night. The culprit is not necessarily your Heating and Air Conditioning unit. The culprit is the closed door.

Your guests won’t tell you if you have a problem. They’re too polite. Your kids probably have their door open when they are small and don’t have a problem. Your teenagers probably don’t talk to you much anyway. How can you know if there’s a problem? It’s a good idea to spend a night in each of the other bedrooms in your house, particularly the guest room, if you have one, to see how the temperature goes with the door closed for eight hours. And do this on a cold night and a hot night. You might be surprised at what you find.

Why do these rooms tend to get off temperature? The answer is they are starved for air. A poorly design heating, ventilating, and air conditioning system, know as the HVAC system in the trade, often does not provide a method for the air to return to the heater or air conditioner except through the open door.

Take a look at your bedrooms. There will be a supply air register or two. But, is there a return air grill? The supply air coming to the room must displace the air that is already in the room. And that air has to go somewhere. When the door is open, the displaced air exits through the door and is sucked up by the return air register in the hallway. Everything is fine with the door open.

But when the door is closed, the air that should be displaced is trapped. When this happens, no new air can get into the room. The “log jam” of air causes a pressure build up at the supply air register and the air in the duct takes the path of least resistance and heads to other parts of the house where there is no resisting air pressure. So the room with the closed door gets no conditioned air and gradually becomes too hot or too cold.

The cure for this problem is to install return air grills in the bedroom. This can be done best by connecting the grill to the return air ductwork so air is taken directly back to the HVAC unit and cooled or heated. If this can not be done due to physical restrictions, a transfer grill can be installed. This can be a simple grill cut in a wall that adjoins the hallway, thus letting the air escape, even when the door is closed. But a direct grill like this will allow sound through, too. It’s better to install a transfer grill in the ceiling and connect it to a piece of flexible ductwork with a bend or two that connects to another grill in the hall. That way the sound can not travel in a straight line and much less sound will be transmitted through the passageway.

Remember, to get the air you want in, you need to let the air you don’t want out. Return air grills or transfer grills are the way to do this. Getting your air conditioning and heating system working optimally is the first major step toward good energy efficiency in a home.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Wearing Passive Solar Design

Bill — Mon, 04 Jan 2010 14:44:55 +0000

It’s freezing cold across much of the United States. Are you wearing passive solar clothes to stay warm?

I know it sounds like an odd question. We tend to think of using solar design for houses, not clothes. I’ll explain.

If you know it’s a cold day, do you think about what you’re going to wear? Of course you do. You might wear several layers. The layering forms more tiny air spaces around you and increases the insulating effectiveness of your clothing. You might pick out dark colors. Even if you don’t think of this as “passive solar dressing,” it is. dark colors absorb the radiant energy from the sun better than light colors. I’m sure when you’re outside on a cold, but sunny day, you walk on the sunny side of the street to stay warmer than you’d be on the shaded side. Ah! Passive solar principles, again. It’s nothing more than proper insulation and receiving the free energy benefit from the sun.

Insulation is important, so let’s not forget your hat. We always hear that we lose the most heat through our heads. Your house loses the most heat through the roof. Heat moves upward as hot air rises. So wearing a warm hat is like putting good insulation in your attic and roof. It’s the place where the investment produces the most benefit.

We do the same thing in the summer, using passive solar principles to stay cooler. Don’t you choose light colored clothes? Light colors reflect the sun’s radiant energy. You’ll stay cooler. A light colored roof in a hot climate will keep your house cooler, too. Don’t you pick clothing that breathes so you’ll stay “ventilated?” Natural ventilation in your attic will reduce your air conditioning expense. It won’t have to work as hard. With the right ventilation in many climates, air conditioning may not be essential, even on the hottest days. On a hot summer day, you might also wear a hat with a big brim. That’s like having a house with proper overhangs to shade the walls and keep the house cooler. The shading keeps you cooler whether it’s a hat or a roof.

I wrote another blog post last winter about using solar energy to help clear my driveway of snow. It’s rare to get much snow where we live in North Carolina. But it happens from time to time. Hey, if Mother Nature is giving us free energy, we might as well use it. It’s simply a matter of understanding how to use it.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

4 Passive Solar Benefits of Metal Roofing

Bill — Tue, 13 Oct 2009 14:34:03 +0000

When you get dressed in the morning, do you consider passive solar design principles? Probably not. At least not conciously. But I’ll bet you consider the weather as you choose what to wear? I do. If it’s going to be hot and sunny, I usually choose a light colored shirt that is made from a fabric that breathes. Experience tells me to avoid black because it will soak up the sun’s heat and avoid a tightly woven fabric because it will trap air next to my skin and make me feel hotter. This is a principle of passive solar design that we use without even labeling it or thinking about it. And you can use these principles in your house design.

Metal roofs, now often referred to as “cool roofs,” can act like your light colored, open weave shirt and keep your house cooler in hot weather. They do this “passively”, that is they use no electricity in the process. Here’s why they work. In an article posted at Classic Metal Roofing Systems website, they list four energy benefits you’ll get with a metal roof.

1. Thermal Mass. Mass is the “weight” of a material. Stone has more mass than wood because a chunk of stone weighs a lot more than a the same-sized chunk of wood. Heavy asphalt roofs have a lot more mass than metal roofs. The higher the mass, the more heat a material can absorb. Although metal can get quite hot to the touch, it does not store heat in its mass and it will give up it’s heat more quickly soon as the sun goes down, or behind a cloud, or even when a breeze blows. So just like your open weave shirt, the material will cool down easily. Aluminum is even better than steel in this regard.

2. Color. Just like your light colored shirt, a light colored roof will absorb less radiant heat. I wrote a blog post about how I use passive solar principles to help clear snow and ice from my driveway. And color was the key. Here’s a link to that article, if you’re interested: http://www.designingyourperfecthouse.com/blog/2009/01/passive-solar-design-on-my-driveway/

3. Reflective Pigment. In the Classic Metal Roof Systems article, they say “Many dark-colored metal roofs now have reflective pigments so that good reflectivity is achieved even in dark colors.” This means that you are not limited to a silver or white roof to enjoy the benefits of an energy efficient, highly-reflective roof.

4. Integral Airspace. Metal roofs do not lay tightly against the roof sheathing. This means that a gap of air is created that insulates the roof sheathing from conducted heat coming from the metal. This airspace acts like a trivet or a pad you might place beneath a hot pan to keep from burning the countertop or table in your kitchen. Asphalt roofs lay tightly against the sheathing and continually conduct heat into your attic or rooms below, adding to your air-conditioning expense.

No matter what roof material you choose, be sure to provide sufficient attic ventilation. Metal roofs do not replace this essential design feature. But metal roofs will keep your attic and house much cooler and keep your air-conditioning electrical costs down significantly.

Metal roofs tend to cost more, initially, than shingle roofs. I’m researching this and looking for ways to control the added costs. I’ll report on this in future posts. If you have any experiences with metal roofing and the energy benefits, please post a comment. I would love to hear from you.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Passive Solar Design – Free Energy

Bill — Tue, 20 Jan 2009 22:59:18 +0000

Today, we awoke to a freak snowstorm here in Raleigh, North Carolina. I say “freak” because any snow is a rare occurrence in this part of the country. Snow in January is a novel concept in the southeast. Everything, and I mean everything was closed. We were crippled by Mother Nature.

When the flakes stopped falling, we had about six inches of nice, clean snow on the ground. I put on my tennis shoes (I don’t have boots anymore since I moved south) and found my gloves (they were in my golf bag where I left them following a chillier than usual round a few weeks ago) and set out to clear the snow. I don’t use a snow shovel any more. I’m not sure I still have one. I use my leaf blower, instead. It works surprisingly well. It fluffs up the snow and blows it away almost without a trace. I cleared my sizeable driveway in a little over an hour. The best part is my back doesn’t hurt!

But here’s the reason I’m writing this post. No sooner had I gotten most of the snow off of the concrete, it started to melt. The air temperature was only twenty seven degrees. The sky was cloudy. But enough solar (radiant) energy still filtered through the clouds, was absorbed by the concrete, and was converted into heat to efficiently melt the dark ice that remained. Here was a perfect example of Passive Solar Design. It’s called “passive” because no mechanical systems are required. It just simply happens. As you might imagine, the portions of my driveway that sit in the shade did not melt. But the totally free energy from the sun did the job for me elsewhere.

Shouldn’t your house be designed to take advantage of this free energy? I discuss this in more detail in my book, Designing Your Perfect House. If a house is designed properly, the sun’s energy will be kept out in the summer by the use of properly sized roof overhangs. You don’t need expensive solar collectors, photovoltaic panels, pumps, batteries or anything. Simple, thoughtful design will make your house energy efficient. A good architect or residential designer can do this for you. And if you live where you might get snow, be sure your driveway is on the sunny side of the house.

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If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Birth of Building Green

Bill — Tue, 20 Jan 2009 15:27:46 +0000

The birth of “Building Green” arguably happened in Austin, Texas in the 1970’s. There’s a good article in Ecohome about Austin’s sustainable building program and their continuing progress. But the trigger for Austin may not have been what you might have guessed. Here is the first paragraph of the article by Jeffery Lee:

Austin, Texas – the state capital and home to the University of Texas – has long been known as a liberal bastion in a conservative state, and the city’s residents are renowned for their environmental consciousness. But it wasn’t the community’s mind-set that led to the establishment of the nation’s first comprehensive green building program; it was a nuclear power plant.

A nuclear power plant and sustainable building and green do not seem to go together. But the question of whether or not the city should buy into a nuclear project led to the introduction of an energy code in 1985 and it started the Austin Energy Star Homes program that spawned the Energy Star program nationally.

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If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Green and Sustainable Building in Historic Old Town San Diego

Bill — Thu, 07 Aug 2008 01:16:12 +0000

Passive solar design, green and sustainable building are not new inventions. Who would have thought that we would be returning to the house design principles of more than a century and a half ago?

I was in San Diego recently and visited the part of town they call Old Town San Diego. I don’t think the buildings are the actual original structures, but they are reproductions that are authentic to the mid 1800′s. One house La Casa de Estudillo, is built in the Spanish Colonial style of the early California settlers. You can see from the photographs that it is built in a “U” shape with a covered veranda wrapping the inside of the “U”. In the center is an outdoor space that is planted and has a water feature in the center.

Green and Sustainable Building in Old Town San Diego

This is passive solar design at its essence. The climate is dry and the sun is harsh. So what did the builders do? They shaped the building so as to create a protected courtyard. The hot sun is kept from streaming into the windows and the thick adobe walls don’t heat up in the sun because they are shaded by the veranda roof. This prevents them from radiating heat into the living spaces. In fact, the high-mass adobe walls will hold the cooler nighttime temperatures, providing a measure of cooling that requires no electricity. After all, they did not have that luxury.

Veranda Roof is a Key to Passive Solar Design

The air that moves beneath the veranda roof is cooler than the air of the sun-drenched desert, so any air that enters the room is also cooler. The shape the building and the use of the veranda as a corridor between rooms means that every room will have openings on two sides so that even the smallest breeze will ventilate the room.

The courtyard is protected from the desert climate making it easier to grow plants that would not survive the desert. But beyond the practical benefits, the courtyard adds to the sense of security. And isn’t this the emotional definition of “home?” It’s our safe haven.

It’s these simple principles that we should be incorporating into our “modern” designs to reduce our demands for energy. The pleasant by-product of designing in this manner is that the spaces become more inviting and comfortable for people. Rooms with daylight on two walls are wonderful. Transition spaces, such as verandas, improve the quality of the spatial experience. Smooth transitions from outside to inside soothe our souls.

And what’s more sustainable than adobe clay, sun-baked clay tiles for the room, and timber cut from the immediate area. Trees, when managed properly, are a very renewable resource.

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If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Some Solar Energy Is Unwelcomed in Summer

Bill — Tue, 22 Jul 2008 01:52:08 +0000

Yikes! It’s nearly 100 degrees here in North Carolina and the humidity nearly matches it. It was still over 90 degrees at dinnertime! I, for one, don’t find solar energy all that welcome this time of year. Maybe if I was generating electricity from it I would feel differently. But the solar energy I’m talking about makes me roast whenever I step out of the shade and it makes my attic a veritable furnace. But, I’ve found a building product that comes to the rescue.

I’m talking about a radiant barrier. A radiant barrier is a reflective material that acts like a mirror to reflect heat back out of the attic just like those silver umbrellas you might have seen or the shiny foil that is wrapped around the space station and satellites to keep them safe from solar rays. When used as roof sheathing, just under the shingles, this same foil radiant barrier can keep your attic much cooler and significantly reduce your cooling costs, up to 30% according to some claims, cutting your energy bills by up to 17%.

I can attest to it’s effectiveness. Since I started specifying LP TechShield roof sheathing, or equal, I’ve noticed that the attics of my porjects have been significantly cooler, even on the hottest days. Not only does that mean that there is less heat transmitted into the living spaces below, but if your air conditioner and ductwork are located in the attic, as many are, the cool, air-conditioned air in the ductwork will stay cooler as it travels to where it is needed. This is a product that will pay for it’s added cost by way of energy cost savings in a very short time.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Bill Hirsch

www.designingyourperfecthouse.com

www.williamhirsch.com

Green Mansions – Part Six

Bill — Mon, 16 Jun 2008 20:26:07 +0000

Sustainable building materials are more and more available these days. “Sustainable” means the materials are manufactured in environmentally responsible ways. They may be made from recycled materials, such as tile or wallboard. Some are made from agricultural wastes, like wheat straw and rice hulls. Still others are made from rapidly renewable materials, such as bamboo or hemp. Wood products from managed forests and “engineered” wood products that make use of all of the parts of the tree, can qualify as sustainable, as can salvaged and reused materials like brick, stone, or slate roof shingles taken from demolished buildings. Newly manufactured materials with long life cycles, like bricks and porcelain tiles, are sustainable in the sense that they do not have to be replaced, so that no future resources are required to manufacture replacements.

Plumbing fixtures that reduce water consumption, landscaping that requires less watering, stormwater management and retention, and materials that limit toxic off-gassing all contribute to making a house “green.” You can do all of these things without changing the look of the house in any way. You might think of this as building a stealth “green” house. You will be building responsibly without making a show of it just to impress your friends and neighbors.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Bill Hirsch

www.designingyourperfecthouse.com

www.williamhirsch.com

Green Mansions – Part Five

Bill — Sat, 14 Jun 2008 20:22:55 +0000

An energy management system can reduce your electric bill and help reduce energy demand at peak times. This system monitors and controls what equipment can come on during certain hours of the day. It may block an electric water heater from starting until an air conditioner that is already running has completed its cycle. Most power companies allow residential customers to switch from the standard residential billing rate to a demand rate, which can be substantially lower if your peak usage is not high. When you change to a demand rate, you allow the power company to monitor your usage throughout the day, checking for peak demand. They will then bill you at a rate that is based on the highest peak they see. The energy management system suppresses peaks by controlling what is turned on, thus controlling your billing rate. You will not be using less electricity, but you will be using it at cheaper times, and you will be contributing to the overall “leveling” of electrical consumption in your community. This leads to less pollution being produced by the power generating plants.

An energy monitoring system can generally pay for itself through savings on your electric bill in about three years. Thereafter, you will be saving about one-third on the cost of your electricity and doing an environmental good deed.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Bill Hirsch

www.designingyourperfecthouse.com

www.williamhirsch.com

“Green” Mansions – Part Four

Bill — Sun, 08 Jun 2008 20:21:57 +0000

When it comes to “building green,” There are other energy-saving measures that can occur behind the scenes. Proper insulation, including draft blocking to prevent convective loops of cold or warm air within walls and ceilings will reduce heat loss in winter and heat gain in summer. I’ve found that in southern climates insulation and building tightness are often not seen as critical issues. This might be because in the north, in the wintertime, we can feel cold drafts indoors and we want to eliminate them. But in the summer, we are not as aware of warm drafts, even though our air conditioner is working very hard and costing us money.
Attic ventilating fans and new products, like reflective faced roof sheathing, do a great job of keeping an attic from overheating, thus reducing the work of the air conditioners. High quality windows and doors, programmable thermostats, lighting that is controlled by dimmers, and compact fluorescent lighting will reduce your energy consumption.

If you would like to read more articles about house and home design, please visit my other website, www.about-home-design.com.

Bill Hirsch

www.designingyourperfecthouse.com

www.williamhirsch.com