Alternative Building Systems Wilmington DE
Alternative Building Systems
How do various alternative building systems compare in price and performance?
Question: How do Rasta block (a concrete form system), aerated autoclaved concrete (AAC) and Durisol (blocks made from recycled wood) compare in price and performance? Performance criteria can include insulating value, structural strength, resistance to termite burrowing, resistance to water, vapor permeability/breathability and anything else you can think of that matters. I'm also interested in comparison of those materials with the Strata International Group's insulated composite described in your May/June 2006 edition, though that product may be too new for good price data. Thanks for any advice you can offer.
Answer: The confusion between nominal, clear-wall, whole-wall and dynamic R-values illustrates the problem of comparing building wall systems. What is needed is an apples-to-apples testing program by an independent agency. The closest approximation to date is that of the Oak Ridge National Laboratory's (ORNL) Building Envelopes Program.
ORNL has tested the whole-wall R-values of a number of wall systems, including conventional wood frame, steel frame, log, adobe and earth blocks, structural insulated panels (SIPs) and insulated concrete forms (ICFs). To view the results, log on to http://www.ornl.gov/sci/roofs+walls and click on Hotbox Test R-value Database. However, with dozens of ICF products on the market, ORNL will never be able to test them all.
The next best source I know of is Supplement D-1 of the Washington State Energy Code (download at http://www.energy.wsu.edu/ftp-ep/pubs/code/bfg/2004/SupplementD_2004.pdf ), which lists the whole-wall R-values of 19 different ICFs.
Unfortunately, the extremely complex nature of heat flow through walls and roofs, which depends not only on the insulating property of the insulation fill but also on the air-leakiness, the presence of heat short-circuits such as framing and rebar, the amount and location of mass, and the local climate, allows for dubious claims by zealous proponents of any system. My advice is to take any and all claims by manufacturers with a heavy dose of skepticism and rely instead on the experiences of as many customers of the product as possible.
Any system approved by your local building inspector will prove structurally adequate. Any product containing wood fiber may be a target for termites, however. You can ensure an adequate interior vapor barrier (necessary in heating climates) simply by priming the interior surfaces with vapor barrier paint (any paint with a perm rating of 1.0 or less).
Cost comparisons are meaningful only when they include labor. Ask manufacturers for the names of contractors experienced in the use of their products. And, as always, get at least three estimates with stipulations on maximum allowed cost overrun.
Philadelphia Flower Show 2018
Dates: 3/4/2018 – 3/11/2018
Pennsylvania Convention Center Philadelphia
1101 Arch Street
The Philadelphia Flower Show, internationally recognized as one of the nation's premiere events as well as the oldest and largest indoor show of its kind, is produced by the Pennsylvania Horticultural Society. PHS has more than 15,000 members throughout the country, offers hundreds of educational programs year-round, and is considered the nationâ�TMs leading authority on urban renewal through greening. PHS's acclaimed Philadelphia Green program restores neighborhood parks, creates community gardens, conducts large scale tree plantings, revitalizes vacant land, engages thousands of citizens in community development activities and maintains treasured public landscapes. Its greening efforts are modeled in many cities across the country.Not sure if you want to exhibit at or attend the Philadelphia Flower Show 2018? See the panels below to get the information you need to make an informed decision.All information in Events In America is deemed to be accurate at the time we add it,and we take steps to verify all details and update our records when new information is provided, but as people, events and circumstances change, we caution users to independently confirm all information. EventsInAmerica.com and Events In America LLC make no guarantee of accuracy and assume no liability for inaccurate information.