There are many conditions that determine the effectiveness of any building material to provide comfort and energy efficient performance. R-Value is only one of these factors or measurement tools.

R-Value is the measure of resistance to heat flow through the defined material. The higher the R-Value the less heat will transfer through the wall, making the system more energy efficient.

R-Value is determined by testing or by the addition of tested components. When “effective” R-value is used, it represents that at a given condition or circumstance, the system performs the same as a product with the “real” R-value.

It is important to understand the conditions at which the “effective” R-value was determined, and see if your application is the same. For example, a masonry wall may have a high “effective” R-value for a 5 hour test period, but have a very low R-value during a 24 hour test period. Where “real” R-value products will have the same R-value during both test periods.

There are several items to consider when evaluating R-Value and it’s effect on your project

Effective R-Value

An example would be masonry products. Masonry product have a very low R-Value but have a high thermal mass. Foam type products have a high R-value but low thermal mass. There is not a standard measurement or number for the energy effectiveness of thermal mass. While R-value resists the flow of heat, thermal mass delays the transfer of heat but does not reduce it. During a short period, thermal mass has the same “effective” R-value, so it is sometimes advertised with this R-value rating. It is not a real R-value but, under those conditions, an “effective” R-value. Please review other technical bulletins for more details and other related items.

Installed R-Value vs Advertised R-Value

It should be noted that R-Value of an item is the value that was tested in a laboratory and is real, but the item may not perform at the same R-value when installed. Most insulating materials obtain their insulating values from trapped air spaces, often the higher the density of air pockets, the higher the R-value. If these air spaces are compressed, a lower R-value will result. For example, batt type insulation may be rated at R-19 in its free state, but requires a 6 ½” thickness to obtain that value. When this material is installed in a 5 ½” frame cavity, the batt is compressed and the R-value is less than R-19. Likewise, putting two batts in the space for one does not increase insulating value; it might even reduce the R-value. Review the Technical Bulletin on Air Infiltration in Insulation for more related information.

Nonuniform Material

Whole wall R-value is the term used to describe the average R-value for the total wall taking into consideration variations and non-uniformity’s in the insulating material. Often, the R-value of the insulating material is advertised without stating the effect of the total system.

An example would be installing an R-19 batt insulation in a 2×6 frame wall. The resultant “whole wall R-value” is the average of the R-19 insulation and the R-5 stud. Tests have shown that the actual “whole wall R-value” of an R-19 wall system to be R-13.7, much less than the R-19 advertised. This applies to all non uniform wall systems.

The R-value of building materials may be effected or altered by the following items.

• Non uniform material
• Thermal shorts
• Material compression
• Air infiltration in the insulation
• Humidity
• Temperature swing or range of environment
• Effects of time and aging.

Along with R-Value, several other factors need to be considered to determine the overall energy efficiency of a building structure.

• Thermal Mass
• Air infiltration in the building
• Radiated heat gains
• Internal heat gains
• Latent and Sensible heat transfer

Originally posted 2010-03-05 00:01:00.

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1. Understanding Thermal Mass Walls in a Passive Solar Design
2. Living a Radiant Life – Understanding Radiant Heat Transfer in Buildings
3. The Skinny on Thermal Mass

• Project Administrator – By default, the person who registers the project with the USGBC will become the Project Administrator for LEED Online. This person should be a LEED-AP (accredited professional), if possible, and should be experienced and knowledgeable about LEED certification projects and process. This person is responsible for managing the assignment of team roles in LEED Online and the management of all of the LEED documentation and coordination throughout the LEED certification process.
• Developer / Owner – This is the person responsible for making the final decisions for the project including all strategies, targets, project goals, financial decisions etc.
• General Contractor – This is the person responsible for the construction of the project and plays a key role in assuring that all of the LEED strategies and design elements are effectively and efficiently carried through to reality. It is helpful if this person has previous experience with LEED or green building projects but not essential if they are included in the process from the beginning of the project and there is a LEED-AP or experienced Project Administrator on the project team.
• Sustainability Consultant – This person is knowledgeable and experienced with LEED, green building or sustainability projects. This person should be a LEED-AP as well and will provide valuable knowledge, resources and structure to the LEED certification process.
• Architect / Designer – This is the person responsible for the architectural design of the building. An architect with experience in LEED or other green building or sustainability projects can skillfully include highly effective, low-cost sustainability strategies into the design of a high performance building such as passive solar design, reduced building footprint, etc.
• Landscape Architect – This is the person responsible for the landscape planning of the site and can also skillfully include a number of highly effective, low-cost strategies into the design that will benefit the project goals and LEED certification.
• Engineers – This category may include Civil Engineering, Structural Engineering and MEP (Mechanical, Electrical & Plumbing) Engineering. The engineers are responsible for a large portion of the LEED criteria, including both pre-requisites and credits and are the key to designing a truly integrated and efficient building design.
• Energy Modeler – This team member will model the energy usage of the building according to the required standards and utilizing the required software platforms that  conform to LEED criteria and a myriad of additional modeling needs that may be included in the project goals such as analysis for tax incentives, energy rebates and additional building or energy certifications for the project.
• Commissioning Authority – This is the person responsible for organizing, coordinating & overseeing the Commissioning of the building after construction and according to the LEED criteria, must have previous experience on a minimum of two LEED projects. Although the commissioning does not take place until after the major building systems have been installed and are operational, it is very helpful to include this team member early in the process so that they can provide valuable information, resources, real-world experience and knowledge from their previous LEED projects.

These team members are essential to the success of a LEED certification and building process and each of the above mentioned roles should be filled in some capacity. As previously mentioned, it is possible that a single team member may fulfill several of the above mentioned roles. For example, it is common for the MEP Engineer to also be the Energy Modeler and even sometimes the Commissioning Authority or for the Architect or Designer to be the Project Administrator and/or Sustainability Consultant. The following list includes some more team roles that are helpful to a LEED certification project and should be included in the Project Team meetings whenever possible:

• Broker / Real Estate Agent
• Marketing / PR Director
• Financial Manager / Cost Consultant
• Facility Manager
• Suppliers
• Key Sub-contractors
• Key Stakeholders (building tenants, users, community members)

EVstudio includes several LEED-AP’s who are experienced on previous LEED certification projects. In addition, EVstudio incorporates green building practices and sustainability strategies into our design strategies for each project. There are many strategies that improve livability without increasing cost. It is our philosophy that sustainable design is sensible design and that many of the most effective strategies require great designers, not great amounts of money.

Originally posted 2009-09-12 00:24:19.

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1. EVstudio Selected for LEED Project in Killeen, Texas
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• Integrate the daylighting scheme into the architecture
• Integrate the daylighting scheme with building systems

These final two points remind us that architecture is synergistic, that is it becomes more than the sum of its parts. They tie the entire daylighting strategy together and their implementation can make or break a design.

Integrate the daylighting scheme into the architecture

Daylighting provides an excellent opportunity to give intentional and unique form to a building. The north, south east and west façades of the building are all in need of different daylighting strategies. This makes it easy to create a solution that is eclectic. At the same time it gives the opportunity to create a dynamic façade that is consistent in fundamentals yet different in the details.

Integrate the daylighting scheme with building systems

Last time we touched on daylight controls. Integrating daylighting systems with building systems goes beyond simple controls. It also has to do with the difference in the color temperature of daylight versus that of electric light. To improve the cohesiveness of the lighting design it is important to specify lighting that is compatible with natural light.

Since reducing electricity use is one of the reasons for incorporating daylighting into a building it is important to have simple controls that dim or switch off the electric light when it isn’t needed. Simple controls are easy to repair or replace and contribute to the success of a daylighting strategy.

Lastly the combination of daylight and supplemental electric light provide an opportunity to reinforce a particular lighting strategy or to play off of it. Realizing the passage of time is a side effect of using natural lighting solutions. This passage of time creates an opportunity to differ the electric lighting strategy in the morning, evening and night to help reinforce the passage of time, something that many occupants are missing in modern buildings.

Originally posted 2010-03-20 00:01:20.

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Schuler Residence in Lake George, CO

Also on the boards is the Evans Residence in Clear Creek County. This home was also designed to be a log home and is designed with a cistern, a greywater system and a composting toilet. This home will have no electricity whatsoever and will have a propane refrigerator and gas lighting. A much more rustic cabin than the Schuler's state-of-the-art home in Lake George, but certainly another approach to going off grid.

Evans Cabin in Clear Creek County

We've done two other off grid cabins in addition to these, both with various systems to qualify them under the current building codes. There are a lot of common systems and synergies that we apply to off grid homes as well as sustainable on grid homes. Most clients who elect for a home off grid are driven to do so because of the economics of bringing in electricity, however many people are now considering these systems for rural, suburban and even urban dwellings. If you are thinking about building a home off grid or are electing to integrate these kinds of systems into any building, give us a call and we can help!

Originally posted 2009-01-26 15:56:39.

No related posts.

Keeping things cool

The first step in passive solar cooling is to simply keep the building from heating up in the first place. Think of all the things that heat up a building:

• The sun
• Lighting
• Computers, etc
• Appliances
• Occupants

Let’s start with the sun. We can reduce the effects of the sun by properly siting a building with a long east/west orientation that utilizes thermal mass and appropriate glazing and window frames. We can also provide shading with exterior architectural features and trees primarily on the south and west. It is important not to block summer breezes as these can help radiate heat away and even pass through the structure.

The next largest heat load tends to be lighting. Through the use of properly implemented daylighting strategies and LED task lighting that heat load can be almost completely eliminated.

There isn’t a lot that can be done with computers and other technology since it is so ubiquitous in our world. However, we can use technology that has a sleep mode when not in use and processors that operate slower and with less heat when we are doing low impact tasks. Even turn off or hibernate computers of occupants who are not there at the time. Proper energy management goes a long way in reducing energy loads.

What office or home doesn’t have a refrigerator or other appliances? The use of low energy appliances reduces heating loads since they are creating less heat through electricity usage.

There isn’t much that can be done about the occupants. With out them we wouldn’t even be having this discussion.

Solar Chimneys

At this point I know you are asking how the sun can be used to cool a building. The simplest way is to create a solar chimney. This is a structure that is referred to as a stack. The stack is essentially a taller portion of the building similar to a tower. It is also a great opportunity for an architectural feature.

The top of the stack is generally black or some dark color and has operable openings. An insect screen is a good idea. The sun heats up the black surface which in turn heats up the surrounding air. This then creates an upward draft since warm air rises. This draws cool air through the building. This cool air can come from a vegetated area, which are typically a few degrees cooler than surrounding air, or through tubes that pass through the earth.

Cool Tower

An alternative to the solar chimney is the cool tower. This also uses a stack feature but works similar to an evaporative cooler. At the top of the tower is an evaporative cooler that draws in air and cools it as it passes through a wet medium. That cool air then falls down the stack and into the space. The motion of the air is supplemented with clerestory windows that allow warm air to be drawn out of the space.

With proper modeling the cool tower can be designed to keep the building cool throughout the warm months. Additional features that go hand in hand with a cool tower are appropriate thermal mass, minimization of summer solar heat gain and supplemental fans to assist in air circulation when needed.

It soon becomes apparent that sustainable design doesn’t hinge on one particular solution. Rather there are a variety of solutions that need to be combined in various ways in order to create a workable solution for a particular building type and climate. Through understanding the fundamentals we have springboard into more in depth considerations and solutions.

Originally posted 2010-03-17 00:01:33.

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1. Solar Hot Water Radiant Heat
2. Understanding Thermal Mass Walls in a Passive Solar Design
3. Basics of Radiant Heating and Cooling with Hydronic Systems

If you have ever walked into a new building or been in a new car you have smelled something distinct, VOCs. Volatile Organic Compounds are what give cars and buildings that new, distinct smell. For many people it is an unpleasant smell and for good reason. VOCs are suspected of causing respiratory problems and even cancer. They can also cause liver and kidney damage as well as nausea and central nervous system damage.

Many building materials such as carpet, pre-finished floors, paints, sealers and cleaners all contain VOCs. Individually it may not be much. But add a large number of products together and that can be the final proverbial straw that breaks the camels back. The other ingredient is the tighter building envelopes we have today. Particularly on high performance and net-zero energy buildings.

Luckily architects, mechanical engineers and LEED APs are knowledgeable about such issues. We can help guide you through the products on your project. If you are doing something simple like painting or replacing your carpet it is worth it to take a moment to read the label carefully to see if it is a low VOC product. If there is no label or it does not contain and VOC information you can look up the products MSDS (Material Safety Data Sheet). If you can’t find that then it may be wise to look for a different product.

Unfortunately there are no hard guidelines for what constitutes a low VOC product. Some manufacturers will advertise their product as such. The South Coast Air Quality Management District rue #1168 provides some guidelines which have been adopted as requirements for points in LEED.

Originally posted 2010-12-31 00:48:07.

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I would like to go into the two basic components of solar hot water,  the collectors and the circulation system.

Collectors

Collectors are the part of the system that collects the radiant energy from the sun and transfers it into the system for use.

Batch collectors:

This collector consists of a dark colored tank or a series of tubes within an insulated box. The water then remains in the system tank until there is demand for the water. This system can overheat if there is low demand so a release valve should be part of the system. There is also another valve often know as a tempering valve that mixes in cold water as needed in order to avoid scalding.

This system is not recommended in climates where freezing occurs. Also by definition it is incompatible with a closed loop system discussed below.

Flat plate collectors:

This is a flat insulated box that is faced in tempered glass and backed with a panel that is painted flat black. In the middles are a series of parallel pipes that are connected on each end with inlet and outlet manifolds.

Sizing varies on climate and family size. In the Denver area 65 SF of collector combined with a 120 gallon tank is a good starting point for a family of 4.

Evacuated tube collectors:

This is the most high-tech collector solution. In this collector there is a series of glass tubes. Each glass tube contains water or glycol and is then surrounded by another glass tube. The air between the two is vacuumed out which insulates the tubes from heat loss.

This collector is the most efficient currently available. It can work in overcast conditions and temperatures of up to 40° below zero.

Circulation

Circulation is how the hot water from the collector gets into home so it can be used. Circulation is a combination of direct/indirect and active/passive.

Active:

An active system uses pumps to circulation the water or glycol through the system. This is the most reliable system but requires energy to operate the pump.

Passive:

This circulation system relies on the natural convection of hot and cold water known as thermosiphon. This relies on the tendency of hot water to rise and cold water to sink. This can be unreliable due to air entrainment and in sufficient temperature gradients.

Direct:

In a direct system the water circulates through the collectors and then either stored in a tank or used immediately. This water is directly used so that the water in the system is the same water that is used to wash clothes or take a shower.

Indirect:

Indirect, also known as closed loop, are the best systems for use in climates where freezing occurs. Here the system circulates a water and glycol solution that does not freeze. The mixture then circulates through a heat exchanger in a storage tank in order to provide hot water.

When used in the correct way, solar hot water can be a great way to provide hot water and reduce our dependency on fossil fuels as energy sources. It is also a good way to reduce energy bills and conserve water. When we know there isn’t limitless hot water in the tank people tend to use water more efficiently.

Originally posted 2010-02-27 00:01:09.

Related posts:

1. Solar Hot Water Radiant Heat
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3. The Six Components of Successful Daylighting

• Assess lighting needs for typical visual needs
• Use of apertures to create focus and mood

These two components are somewhat advanced strategies the breathe life into the space and make it more dynamic, all with out resorting to electrical lighting for the majority of the day.

Assess lighting needs for typical visual needs

Daylighting must address the needs of the visual task that is to be performed within the space. The lighting level needs of an occupant vary between warehouse space and office space. Therefore the amount of light provide by the daylighting strategy must be also vary.

Placement of the daylighting aperture and its controllability are critical. The quantity and quality standards set forth by the Illuminating Engineering Society of North America (IESNA) is applicable to daylighting and is a great resource.

It is also good to keep in mind that the best daylighting strategy may need supplemental electric task lighting as well. This is particularly true in early morning and evening situations.

Use of apertures to create focus and mood

The use of natural light to illuminate a space doesn’t mean that the light levels need be uniform throughout. With special consideration of the size and placement of apertures, daylight can be directed to accentuate a design, indicate important spaces and act as a wayfinding strategy within a building. Scale models and digital models are excellent tools in exploring different strategies.

Another aspect to these apertures is that they can perform double duty. An efficient lighting solution can be incorporated so that in the evening and night the same visual impact is created. Light sensors ensure that the electric lights only come on when light levels dip below a predetermined threshold.

Next time we will wrap up with the final two components: integrate the daylighting scheme into the architecture and integrate the daylighting scheme with building systems. See you then.

Originally posted 2010-03-16 00:05:25.

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Less than 20% of firms surveyed consider themselves to be experienced with green design

86% of firms believes there is more cost in going green

78% of firms said that their clients believe there is added cost for going green

Its fascinating that less than 1/5 of firms are experienced with green design. It is a part of so many of our projects whether they are LEED or not that I believe this experience is critical. The debate about cost of "going green" is a fascinating one with no easy answer. In my experience some of the developers of LEED buildings will say it doesn't ratchet up initial cost and some will say they're really paying for it. I think a lot of that comes back to definitions of what constitutes green and which LEED credits you are going after. Some of the LEED points are "free" and some of them involve altering the design. You're always stuck with additional commissioning charges but the other cost differences come down to cost.

On a related note they mentioned that several groups including restaurants and universities are conflicted over LEED not always addressing their specific uses. This was/is an issue with some housing building types and the USGBC invented the LEED Homes to address that. He also mentioned that the USGBC bills over $400K per employee. Wow.

The point of all of this was that firms need to be careful about what they promise and how they define green. It can be a moving target and there is some reliance on the USGBC for interpretation.

In the end EVstudio is committed to picking strategies that are practical and if a certification is desired, we'll work with our clients to pick the most appropriate path to get there.

Originally posted 2008-06-04 17:29:58.

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1. Welcome

The first step is to become a LEED Green Associate. This can actually be gained as a standalone credential or as part of becoming a LEED AP with Specialty. There are a number of basic requirements, taken from the USGBC website:

For professionals who support green building design, construction, and operations, the LEED Green Associate credential denotes basic knowledge of green building principles and practices and LEED.

Eligibility requirements:

Candidates must have experience in the form of

•             EITHER documented involvement on a project registered or certified for LEED

•             OR employment (or previous employment) in a sustainable field of work

•             OR engagement in (or completion of) an education program that addresses green building principles.

Credential maintenance requirements:

LEED Green Associates must maintain their credential by earning 15 continuing education (CE) hours every two-year reporting period.

As you can see even gaining the basic level within the LEED AP tree a candidate must some substantial experience in the green and sustainable building fields or at the very least a fairly robust education which addresses those issues.

The most important aspect is that continuing education is now a requirement even for the base level of LEED Green Associate. This prevents the accreditation from being a “get it and forget it” addition to one’s business card.

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1. Anthony Ries becomes a LEED AP BD+C
2. LEED Certified Buildings and Accredited Professionals
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