tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science/79 2008-05-07T14:25:04Z HGTVPro.com contributor Eric Helton discusses the science behind the best practices for homebuilding. Movable Type 3.33 tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2826 2008-05-07T14:03:11Z 2008-05-07T14:25:04Z

A while back, we were lamenting the design aesthetics (or lack thereof) of many of the thermostats in our houses. It's nice that there are more and more thermostats being offered with sleek designs. The same can finally be said...

Eric Helton Kidde Silhouette is an attractive alternative to historic smoke alarm aesthetics. ]]> Of course, ANY smoke alarm is better than no smoke alarm, but this sleek, model is a good compliment to many interior designs. I don't mean to bash the bulkier models, as they do their important and noble jobs. That's really what matters. The Silhouette runs on AC power and has an internal battery backup. This is the type of system required by code currently in new construction. Multiple units can be interconnected so they all sound when any of them detects an alarm situation. In a retrofit, if the house already has AC-powered smoke alarms, it's an easy swap. If the current alarms are battery powered only, an electrician should be consulted. Feel free to comment if there are other similar products out there. If there are, I haven't run across them yet. It's a big world, and we can work as a team. Take care, -e tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2683 2008-04-09T16:45:22Z 2008-04-09T18:19:13Z

Energy Star has released information about the Energy Star Water Heater criteria that will take effect in January 2009. This is exciting news, as water heaters had not been Energy Star certified prior to this, and it will help people...

Eric Helton Energy Star Water Heater criteria that will take effect in January 2009. This is exciting news, as water heaters had not been Energy Star certified prior to this, and it will help people make informed decisions about products' energy efficiency and potential long-term cost savings. Depending on the type of water heater, choosing an Energy Star model is estimated to save 7.3 to 55% of typical annual energy use for water heating. This relates to $26 to $277 a year. ]]> Department of Energy's website dedicated to water heaters if you wish to learn more about the different technologies and their advantages/disadvantages. Here is a rundown of the minimum Energy Factor levels required for Energy Star certification for residential water heaters in 2009: * Gas storage water heaters: EF of 0.62 * Gas condensing water heaters: EF of 0.80 (plus some other performance caveats) * Whole-home gas tankless water heaters: EF of 0.82 (plus some other performance caveats) * Heat pump water heaters: EF of 2.0 Solar thermal water heaters have requirements of a minimum solar fraction of 0.50 and a Solar Rating and Certification Corporation (SRCC) OG-300 certification. Check out the DOE press release and these two blog entries for details and other ways of looking at this: DOE press release groovy green CleanTechnica]]> tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2587 2008-03-27T18:45:55Z 2008-04-01T17:11:41Z

Here is a nice article about work our friends at the Oak Ridge National Laboratory (ORNL) have been doing with Habitat for Humanity in Tennessee....

Eric Helton ORNL) have been doing with Habitat for Humanity in Tennessee. ]]> Read the article here. ]]> tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2630 2008-03-21T21:36:06Z 2008-03-21T22:21:00Z

A high-performance house client from a few years back just sent me an email saying he has opened a retail store for environmental and sustainable products. He asked me if I could point him toward some products for homeowners to...

Eric Helton A high-performance house client from a few years back just sent me an email saying he has opened a retail store for environmental and sustainable products. He asked me if I could point him toward some products for homeowners to monitor their electrical usage. I figured I'd share the list as an easy entry for a Friday afternoon. :) Plug in power meters: P3 Kill A Watt (several models) P3 Kill A Watt Power Strip Brand Electronics Watts up? Brultech EML 2020 UPM EM-series Whole-house meters: Blueline Power Cost Meter The Energy Detective (TED) Brand Electronics Cent-a-Meter Wattson Home Joule Energy Monitor EM-2500 ]]> tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2585 2008-03-17T16:55:21Z 2008-03-25T20:11:26Z

A study just released by ABI Research says that the market for home automation and security systems is beginning to open up. Costs of systems and components are coming down, and the technologies are becoming much more accessible to the...

Eric Helton ABI Research says that the market for home automation and security systems is beginning to open up. Costs of systems and components are coming down, and the technologies are becoming much more accessible to the non-techie. Are we going to see advances in energy efficiency due to the control such systems may have over the HVAC, lighting, and other electric loads? Or, will it be adding electrical consumption to the house where there currently isn't?]]> Pittsburgh Home and Garden Show this past weekend, I didn't run across any companies that did much in home automation or integration. I talked to one company that specializes in security systems, but does some home sound and theater work. This isn't a big market for new technologies nor perceived expensive technologies, unlike some other markets here in the States. I think there is a lot of potential for integrating all of the various home technology systems to provide energy savings at the same time as offering enhanced experience and comfort in the home. As these systems become cheaper and offer more benefits, greater market penetration will undoubtedly advance the technology and provide more and more integration and utility. We can hope this will also bring lower energy use and bills... You can read more about the study from Tekrati.]]> tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2481 2008-02-23T22:16:18Z 2008-02-25T22:42:46Z

This was the title from a colleague's paper recently presented at the Buildings X Conference. Yes, it's a little dry sounding, as it was written for a building scientist crowd, but I want to discuss some aspects of the type...

Eric Helton colleague's paper recently presented at the Buildings X Conference. Yes, it's a little dry sounding, as it was written for a building scientist crowd, but I want to discuss some aspects of the type of construction used in the high performance house where this study took place.]]> HERS score is 91, using the HERS 1999 methodology. The house is very airtight and has great windows, upgraded wall insulation, and efficient HVAC equipment. So, that's a little of the general background on the house. Let's get back to the cathedralized attic and the issue of conditioning it. A cathedralized attic (more or less) means that the insulation is located at the roof instead of the attic floor. This brings the attic volume into the thermal envelope of the house. A good way to accomplish this is to use some sort of sprayed-in foam insulation on the underside of the roof deck. Done correctly, this can provide a well-insulated space for location of the heating and cooling equipment and ductwork. Location in conditioned space is really the only way to optimize performance of the heating and cooling system. Note, that a conditioned basement, sealed crawlspace, or indoor mechanical room are other possible ways of installing the equipment in conditioned space. If the system and the ductwork are inside the thermal envelope, they will not be affected by the outside temperature and can provide better comfort with less energy loss. The paper looked at whether there was any advantage to directly conditioning the attic space with supply and return registers. The alternative is to only provide ductwork to the living space and allow the attic to be indirectly conditioned by the spaces below it. His results show that it's better to allow the attic to be indirectly heated and cooled. He found that the system ended up overcooling and overheating some areas of the living space more frequently when the attic was directly conditioned. The energy use was also higher when the attic was conditioned directly. Note that this house is located in a hot, humid climate, and these conclusions may not hold true in different climates. -e ]]> tag:blogs.hgtvpro.com,2008:/hgtvpro/building_science//79.2375 2008-01-29T19:46:23Z 2008-01-29T20:22:17Z

Happy New Year! January has screamed by somehow. I spent most of the past two months on the road, but am back in the office and excited to share some of the things I've learned at the conferences I've been...

Eric Helton Happy New Year! January has screamed by somehow. I spent most of the past two months on the road, but am back in the office and excited to share some of the things I've learned at the conferences I've been to. Thermal Performance of the Exterior Envelopes of Whole Buildings X. The conference was put on by the Oak Ridge National Laboratory. There was a great showing of people from all over the world interested in how buildings perform. I just got back from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 2008 Winter Meeting and the AHR Expo. The technical program at the ASHRAE '08 Winter Meeting had a lot to offer over the four days of parallel technical presentations. ASHRAE has technical committees and groups devoted to advancing technology, research, standards, and other aspects of the industry. The AHR Expo was a blast. I spent two full days wandering the Expo, talking with manufacturers about the bazillion of products out there for our industry, and I didn't even cover all of the show. Commercial-scale products certainly dominate the landscape, but there are a lot of manufacturers offering products for the residential sector. There were a lot of exciting new types of equipment, services, and software out there that we'll be seeing in houses soon, if not already. As I dig myself out of the pile of unread emails and backlog of work here in my office, I'll talk about some of these as I enter them into my file folders. Thanks and take care, -Eric]]> tag:blogs.hgtvpro.com,2007:/hgtvpro/building_science//79.2130 2007-12-03T02:58:37Z 2007-12-03T19:59:01Z

All right, there has been a great response to the post asking what you all thought about thermostats. Thanks to everyone who contributed. There is a lot of good information in your comments. It's funny how we use the term...

Eric Helton All right, there has been a great response to the post asking what you all thought about thermostats. Thanks to everyone who contributed. There is a lot of good information in your comments. It's funny how we use the term thermostat, like it's an easily defined product that simply controls temperature. However, the variation in experiences indicates it's not so simple. The comments show that it is hard to talk about one component without bringing other components of the house into the conversation. It's clear that the thermostat is not solely responsible for the thermal comfort in the house; all sorts of other things matter. This is a challenge.There are a lot of factors involved in keeping the people in a house comfortable and not the least is that comfort itself is not a constant from person to person, nor even for one person at all times. Here is a summary of your comments and some further discussion of some of the topics. This is why building scientists and design teams look at the whole house as a system and try to balance all aspects of the design and expected use in a house so the final design has the best opportunity to provide a comprehensive package of performance, utility, and aesthetics. By my unscientific accounting, it looks like more than half of the respondents are using programmable thermostats, although half of those folks find them lacking in some way. That's an unfortunate acceptance level for a technology that is marketed as having the ability to save a lot of energy. There are a lot of reasons why the programming function fails some users. It's too complicated for some. It's too simplistic and inflexible for others. Houses are built differently and there are many types of heating and cooling systems that can be in the house. Every situation is unique and an educated choice really needs to be made to find the best controls for the heating and/or cooling system. Used correctly, they do offer a lot to many people. As an example, my mother would be ill-served by a programmable thermostat. Her schedule changes throughout the week, and she simply turns the thermostat up or down as she leaves or returns. She has a forced air furnace and an air conditioner. Her house has a quick response time when recovering from setback (or set up in cooling). On the other hand, my house has no cooling, and heating is accomplished by cast-iron radiators heated by a boiler. On cold winter days, it takes my system about 2 hours to recover from the 59F setback temperature so it is 67F when we get up at 6 AM. Similarly, my wife and I are out of the house during the daytime hours, so it makes sense to drop the heating setpoint when we leave for work and have it programmed to have the house back up to temperature around the time we return. The programming feature is very important for us and surely saves a lot of money on our winter heating bills. When our schedules change, the programming is easy enough for us to alter or override. I love Laura's idea of having a "tomorrow is a holiday" button so the thermostat knows to use the weekend programming on days I'm working from home. Several folks commented that they would like to have a thermostat with a larger, backlit display. As someone pointed out, there are large text models on the market, but it's not necessarily what's in your house already or easy to find at local retail stores. Thermostat location height on the wall is also tied to this. I agree that, frequently, the thermostat is mounted below eye level (at least for me). I suppose I don't mind crouching a little because the alternative would be that a shorter person wouldn't be able to see it at all if it were mounted higher. Maybe someone who does installation can comment, but I also think that the lower position does a better job of measuring the temperature nearer the middle of your body. Most of the time, the floor will be colder than the air near the ceiling. This stratification plays into comfort and the system controls. A single point measurement is not really ideal for characterizing the temperature throughout the whole house (or zone), especially when there are multiple floors, long distances to certain areas, or high load areas like sunrooms or exercise rooms. It becomes the responsibility of the heating/cooling contractor and whoever designed the system to balance the airflows to provide adequate distribution of conditioned air and to make sure the system is designed correctly. Multiple temperature measurement locations may be better in some situations (like in a zoned system). Thermostat mounting is also an art. The contractor's unfortunate responsibility is to find a good location that is accessible and more or less representative of the average temperature of the space. It cannot be unduly affected by direct sunlight, drafts, internal loads, etc. Unfortunate to the aesthetics of many, this location may end up in the middle of a wall, making decoration difficult. While some may be more pleasant to look at than others, most thermostats are relatively neutral in appearance. Todd mentioned one thermostat as an example of manufacturers addressing the aesthetics. It has a modern, clean design that sticks out less from the wall than many we've seen in the past. There are many choices in appearance as well as functionality, however there are limits to what you can find on the self local to you or available through local HVAC contractors. So, in short, it seems that some are finding thermostats to be either too complicated or too simple, bulky and ugly, ineffective as a gauge of the whole-house's thermal comfort, and usually located in less than ideal locations. As I mentioned earlier, this is an unscientific study with a lot of bias, I would assume. I know there are a whole host of people out there that are happy as clams with their thermostats, and who set them and forget about them. One thing I was hoping to get some insight into was home automation systems. There are some slick systems out there that combine the controls for several systems in the house into one interface (sometimes with multiple locations). For example, an architect I know built a house for himself with a home automation system that combines temperature control for the various zones in the house with the security system, lighting, and audio. He can also 'log into' his house from afar and make sure the lights are off or tell the furnace he won't be home from work until 8 PM and to have the house warm or cool for him then instead of his normal 6 PM. I think this is an interesting topic that I don't have the space to discuss further here and now. Please leave comments if you have any experience with home automation systems. I'll put together some information as well, and we can do another round in a week or so. tag:blogs.hgtvpro.com,2007:/hgtvpro/building_science//79.2031 2007-11-09T16:35:01Z 2007-12-03T03:07:15Z

In mid-October, I attended an annual conference put on by the Energy & Environmental Building Association (EEBA). It was a fun event with a spectacular mix of great folks: builders, home energy experts, product manufacturers, building scientists, utilities, nonprofits, and...

Eric Helton Energy & Environmental Building Association (EEBA). It was a fun event with a spectacular mix of great folks: builders, home energy experts, product manufacturers, building scientists, utilities, nonprofits, and people who are simply interested in green building. There were lectures tuned to the interests of every group and lots of fun products to play with at the manufacturer's expo.]]> Sarah Susanka, architect and author of the Not So Big House series and, more recently, the Not So Big Life: Making Room for What Really Matters. I applaud the folks at EEBA for inviting her to speak. Her key messages for both architecture and life revolve around holistic simplicity, good design, and the ethos of quality over quantity. I'm probably incapable of doing her work justice, so I'll leave it at that. Check out her websites and/or spend few minutes on the web searching. It will turn up more than enough information to decide for yourself if you wish to read any of her books. Another fascinating presentation was one on ultra-low energy, green homes being built by two builders following the Passive House standards. A combination of great insulation, high-performance windows, passive solar design, and very airtight construction (mechanical ventilation is required) allows the heating and cooling systems for the house to be very minimal and less expensive. The houses don't have to be expensive, either. e-co lab has built Passive Houses for low-income families, as well as done market-rate, upscale, and renovation work. Conservation Technologies also presented two Passive House projects they are working on in/near Duluth, Minnesota. For further information: Energy & Environmental Building Association (EEBA) Sarah Susanka Not So Big Life: Making Room for What Really Matters e-co lab Conservation Technologies ]]> tag:blogs.hgtvpro.com,2007:/hgtvpro/building_science//79.2030 2007-10-31T16:33:01Z 2007-12-03T03:06:08Z

Hi friends, I wonder how this is going to work. I've said before that I'd like to have this blog be a bit of collaboration, instead of me just whistling into the Internet. So, I'd like to tap into your...

Eric Helton Hi friends, I wonder how this is going to work. I've said before that I'd like to have this blog be a bit of collaboration, instead of me just whistling into the Internet. So, I'd like to tap into your brains and lives for some perspective. Each of us interacts with the world and the things in it very differently, but the products companies give us show more insight into the engineers' or marketers' thoughts than the users' much of the time. It's the same way with the researchers. We all need to talk to help companies make better products and researchers to study things that will help that happen. So, what do you think of thermostats? How do you use them? What do you like or dislike? Where would you like to see them go in the future? Are they difficult to use or read or program? As you sit at your computer, do you have any clue what the setpoint of your system right now is? Do you really care? Do you feel that it has anything to do with how much energy your house uses? Would more functions and operability be of use to you, or would you like less? Is there anything else you would like them to do, control, etc? Throw it all at me! We'll see what comments and emails come in, and I'll talk about them next week. Thanks! tag:blogs.hgtvpro.com,2007:/hgtvpro/building_science//79.2029 2007-10-24T16:29:29Z 2007-12-03T03:04:52Z

I had the opportunity to work with one of the teams for the 2007 Solar Decathlon competition that recently took place in Washington, D.C. Twenty teams of students from colleges and universities across the United States and several other countries...

Eric Helton I had the opportunity to work with one of the teams for the 2007 Solar Decathlon competition that recently took place in Washington, D.C. Twenty teams of students from colleges and universities across the United States and several other countries pit their engineering, architectural, and communication skills against each other to build energy efficient, attractive, solar-based houses. Solar Decathlon website website to check out the houses and teams. I was able to spend some time with several teams during the setup process in Washington. Though understandably frantic at times, the energy was overall very excited, passionate, teamwork-oriented, and dedicated. It was beautiful to experience. I'm looking forward to seeing what these students make happen in the world after they graduate. 2007 Solar Decathlon]]> tag:blogs.hgtvpro.com,2007:/hgtvpro/building_science//79.2028 2007-10-17T16:17:31Z 2007-12-03T03:05:27Z

Hi Everyone. I've been asked to put my $0.02 into words for this group of folks interested in making the houses we live in as good as possible. My day job is with a company that tries to bridge the...

Eric Helton Hi Everyone. I've been asked to put my $0.02 into words for this group of folks interested in making the houses we live in as good as possible. My day job is with a company that tries to bridge the gap between homebuilding research and real life. We work with builders to build better houses. Sometimes, this means a full-out "green" home. Sometimes we simply help the builder construct houses that are more comfortable, durable, safe, and efficient than a standard code-built house. These houses typically use 30-40% less energy during the course of a year. On one hand, we get to do research into all sorts of fun, hair-brained schemes at saving energy while providing comfort and a healthy environment. On the other hand, we get to work with builders and architects to aid in an integrated design that can result in a better house at little to no extra cost. So, a little about me... I'm trained as a mechanical engineer and building scientist. I've been working in various aspects of the green building movement since 1999, but I've been thinking about these things for at least a decade longer than that. However, while I love this stuff, there are all sorts of other fun things to do in life. So, I make time to paddle my canoe, camp, ride my bike, view and make art and music, renovate my house, and to sit on the couch reading a book with my wife, dog, and cat. In this blog, I will be making posts about results (good and bad) from myriad research projects going on in the green and high-performance building world. The fun part is to show how the research can inspire our everyday lives. Social, economic, and philosophical musing are going to work their way in at times, as they make up the context for anything we do. I'd love to hear from you. Why are you reading this? What do you want to get out of it? How can this blog help enable any of us to improve our lot in life, or at least create a comfortable, safe, and efficient nest in which to curl up on a couch? Thanks and take care! -Eric