A new, updated and revised “Greenblock Installation and Technical Manual” is now available online or on CD. Click Here to view the online version or contact your Greenblock Territory Manager for a CD.

Everyone knows that ICFs provide an exceptional building envelope for both residential and commercial construction. But there still seems to be some confusion and conflicting opinions relating to the actual R-value of an ICF wall.

R-50 seems to be a number that is repeated frequently throughout the industry, but in reality that is a difficult number to quantify.

At Greenblock we like to refer to a term coined by the ICFA, “The ICF Effect”, which we feel is a much more accurate measurement of the true R-value of one of our wall systems.

The ICF Effect is made up of three components;

1. Continuous, stable R-value of the molded EPS foam panels

2. Reduced air infiltration through the ICF wall

3. Thermal mass moderation

R-Value: The molded EPS foam in a Greenblock ICF has a tested, actual R-Value of approximately 4.4 per inch of foam, which equates to an R-23 for our Fixed-Web and GBLOX products and an R-18 for our 2-4-2 product.

Reduced Air Infiltration: ICF walls provide a virtually airtight, monolithic foam and concrete barrier with no cracks, gaps or crevices and no thermal bridging.

Thermal Mass Moderation: The concrete core in an ICF wall offers the characteristic thermal mass qualities of heat absorption and thermal lag, thus reducing and delaying the transfer of heat or cold to the inside of the building.

So based on the ICF Effect, what is the R-Value of a Greenblock wall? Well it’s still difficult to quantify with a number. However, what we can say is that based on documented testing, homes and buildings constructed with ICFs typically require 44% less energy to heat and 32% less energy to cool than comparable structures built with traditional materials.

And whether you own a home or a large commercial building, that translates to more money in your pocket at the end of the month.

Click Here to learn more about the ICF Effect

Greenblock has begun manufacturing at FMI in Post Falls ID. "FMI is an experienced ICF molder which will allow us to service the Pacific Northwest with quality product at lower prices and shorter lead-times”, says Dan Smith, Greenblock’s Northwest Territory Manager. “FMI understands the ICF business in terms of the quality and level of service required. I’m looking forward to a great partnership with them as we introduce Greenblock to this part of the country”, continues Smith.

Good news for the ICF Industry

NAHB has thrown its considerable support behind the proposed 2012 International Energy Conservation Code which calls for a 30% increase in energy efficiency for new homes over the 2006 model codes.

This is exciting news for the ICF industry because policymakers are calling on home builders to meet these reductions through improvements in equipment, appliances and the building envelope.

Greenblock ICF wall systems create an airtight building envelope providing exceptional R-values. Homes built with ICF exterior walls and the proper complement of windows, doors, HVAC systems, and methods, generally accomplish at least a 50% savings in heating and cooling. In some cases, depending on the area and climate, home owners experience as much as a70% decrease in energy use and costs.

Home builders are taking a closer look at ICF construction as a cost-effective way to meet these new requirements. Read the full article

Pulte-Centex merger could signal housing market rebound.
Deal creates largest homebuilder in U.S.

Pulte Homes Inc. will become the largest homebuilder nationally and in Central Texas, catapulted to the top by a planned merger with Centex Homes that some local experts say could signal a housing market rebound.

Local developers say more consolidations could follow as homebuilders try to survive the worst housing downturn in a generation. The merger was announced Wednesday and is expected to become final later this year. In Central Texas, the merger pairs the second- and third-largest builders: In 2008, Centex sold 767 homes, and Pulte sold 665. The combined company will operate under the Pulte name.

Housing industry analysts say the merger could be an early sign that the housing market is beginning to recover. Pulte wouldn't combine with another large national builder if they didn't think there were several markets that had fairly positive outlooks. This merger is consistent with the objectives of most builders today, which is to survive until the market improves.

That might be starting to happen: The Commerce Department said new home sales climbed 4.7 percent in February. "We have some measured optimism," said Centex's Bruner. "We're beginning to see early signs of stabilization in the housing market nationally."

Builder: Homecrete Homes Inc, Stuart Florida
ICF Installer: Insulated Concrete Walls Inc.
Size: Ten homes ranging in size from 2500-3000 sf
ICF Used: Greenblock 4" core Panel System. Lite-Deck 6" Flooring System

The Enclave is a private, gated community of ten individually designed classic courtyard homes. Each home at The Enclave will be built green with the highest standards of eco-friendly materials and energy smart appliances certified by the Florida Green Building Coalition.

Construction of the first home, which will serve as the model center for the community, began mid-December 2008 and is scheduled to be complete and ready for occupancy by March 2009. Additional construction of the remaining nine homes will begin throughout the next six months.

If you look closely at a Greenblock ICF you’ll notice that the interior surfaces are not smooth.  Spaced at varying widths depending on the product, each of our ICFs has vertical dovetail-shaped channels molded into the foam that run from the top of the block to the bottom. These channels serve a dual purpose; first, they create an excellent concrete-to-foam bond which greatly reduces the possibility of bulges and wavy walls. Second, each interior channel on a Greenblock ICF is designed with a “shelf” at the bottom. When concrete is placed in the block it fills the channels and settles on these shelves, holding the block down, thus reducing lifting during placement.

Greenblock ICFs require no glue, ties or straps between courses so our walls go up fast, plumb, level and square.

Interior wood or steel-framed walls are easily attached to Greenblock ICF walls.

The issue of how to fasten wood or steel-framed walls to the exterior ICF shell is a common concern for builders new to our industry. Fortunately, these attachments are easily made. Like many of the questions these contractors have with ICF construction techniques, there are several solutions, all of which are relatively simple and straightforward.

Non-Structural Connections:

The easiest way to tie framed walls into the Greenblock concrete shell is to take advantage of the furring strips which are spaced on six inch centers. If the location of the interior wall aligns with a column of ties, it’s simply a matter of driving a series of 3-inch drywall screws through the stud and into the furring strips.

One drawback to this method is that your walls may not match up to the furring strip location, however Greenblock’s 6” OC 1 5/8” wide furring strips offer more attachment options than our 8” OC competitors.

Tom McClain, core products manager at Simpson Strong-Tie, says this method is probably adequate, although he would recommend something a little stronger for long walls. “It’s probably okay for small rooms,” he says, “but personally, I’d put something a little more solid in there. If someone tips over a dresser, or slams a bed against the wall, I’m not sure that that type of connection would hold.”

Some contractors claim that positively attaching framed walls to the ICF shell is unnecessary. Ted Hartner, manager of residential sales and marketing at Dietrich Metal Framing says. “Interior walls are secured using the floor and ceiling diaphragms, so the connection to the exterior shell is secondary.”

Floor connections are simple. So are the ceiling connections for walls that run perpendicular to the trusses. Walls that run parallel to the trusses, however, need a little more work. Blocks are set between the joists or trusses at regular intervals, and the walls are attached to the blocks. “Blocking requirements are something the structural engineer has to call out,” notes Grant Ricks, a senior project engineer with Rudolph & Sletton. He added that interior walls should not be framed too tightly against the trusses. “If the wall becomes bearing, it alters the forces within the truss,” which could potentially weaken the entire roof.

“On most walls, you can set the roof trusses right on top of the wall,” says Hern, “but [in cold climates] you have to account for a fairly significant snow load.” His current project involves a nearly flat roof with 38-foot clear span. “It will flex up to ¾ of an inch with the snow load, and has to be allowed to float, so we can’t have a rigid connection,” he says. Deprived of a ceiling connection, he secured the interior walls by tying them to each other.

Heavy Duty Attachments:

Occasionally plans may require a solid, structural connection between ICF walls and the interior. Three options exist:

The first is to use anchor bolts. Often used to attach ledgers and sill plates, the process is virtually identical when used to attach walls.

The second method is to use Simpson’s ICF Ledger Connector (ICFLC). Made of 14 gauge steel, the piece is inserted through a vertical slot in the foam prior to the pour. Once the concrete has set, the framed wall is secured to the exposed steel flange with screws.

The product was designed specifically for ICFs, says Simpson’s McClain, and works well in foam up to 2 ¾ inches thick. He recommends using it on all stud-to-ICF wall connections, but admits that price-conscious home buyers may be reluctant to pay $6 to $8 for a non-structural part.

A third option is to use the ICF Connector from ICF Connect, Ltd. The connector consists of two pieces of stamped steel, inserted through vertical slots cut in the ICF foam. For a regular 2x4 wall, the plates would be inserted 3 ½ inches apart, just wide enough for the stud. Once in place, the wood or steel stud can be secured to the plates with #6 pan screws.

According to a recent survey conducted by McGraw-Hill on behalf of the NAHB, Green Building is the single-biggest wish list item on home buyer’s minds, and the trend shows no sign of slowing. They want their new homes to be environmentally friendly and they want them built by builders with knowledge of green construction methods.

Creating Demand in a Down Market:

Builders of green homes report being less affected by the economic downturn than their conventional competitors.

“40% report a marketing advantage from green homes in today’s housing slump, with 16% finding a much easier time of selling their homes.”
(SmartMarket Report: The Green Home Builder, McGraw-Hill, 2008)

Triggers for Green Home Building Expansion:

• Energy costs/utility rebates
• Emphasis on efficiency
• Differentiated performance
• Consumer demand
• Competitive advantage
• Increased education

Greenblock Homes Just Makes Sense:

Lower operating costs, health and comfort, sustainable design and federal tax credits all contribute to the increasing demand for green-built homes. Several federal and state agencies, along with many private lenders, offer special financing incentives for buyers of environmentally friendly homes.

Builders of ICF homes say there is no difference in permitting an ICF home, and construction times are often shorter than with conventionally constructed properties.

What are you Waiting for?

Less than five months after its introduction, nearly 800 builders, remodelers and other industry professionals have earned the Certified Green Professional™ designation from the National Association of Home Builders (NAHB).

The rush to achieve the new educational designation is another sign that NAHB members continue to lead the home building industry toward resource-efficient home building, said NAHB President Sandy Dunn, a home builder in Point Pleasant, W. Va.

The Certified Green Professional designation is issued by the NAHB University of Housing, the educational arm of the association. The designation is part of the NAHB National Green Building Program, which also includes a green home rating system and scoring tool at www.nahbgreen.org.

It's designed for all home building industry professionals, from builders and remodelers to real estate agents, designers and marketers, and is open to non-NAHB members as well. Earning the designation requires taking a 16-hour Green Building for Building Professionals class, eight hours of business management instruction and a minimum of two years of industry experience. Designees also must adhere to a prescribed code of ethics.

Texas claims the greatest number of Certified Green Professionals, with 107 designees. Other states with high numbers of designees include North Carolina, Florida and Indiana, but there are some in every state. Consumers can use the "Find a Builder or Remodeler" search engine at www.nahb.org to find a local Certified Green Professional.

Educational specialists continually work on refinements to the Green Building for Building Professionals class content. "Green building is very dynamic, reflecting new technologies and the growing experience of many of our members," Dunn noted. "NAHB is keeping on top of these changes."

Attend the 2009 National Green Building Conference in Dallas on May 10-13 to learn more about the critical paths to green building, and to participate in interactive sessions and be part of the driving force for the green building and remodeling markets.

For more information and to sign up to be notified when registration opens, visit www.nahb.org/GreenBuildingConference.