Alternative Wall Construction | <– Date –> <– Thread –> |
From: Charles Ehrlich (chasinnernet.com) | |
Date: Fri, 14 Oct 94 01:13 CDT |
I've recently completed some research on alternative building products (walls) and techniques. As it seems there is quite a bit of interest in energy efficiency in this group, and because I'd like to expand my list, I present it to you here. Apologies in advance for the poor formatting. This is a list of my preferred alternative building products and methods, mostly for walls, in order of my personal preference. InteGrid Building Systems J. Gregory Otto, President 1396 Campus Drive Berkeley, CA 94708 (510) 845-1100 Phone (510) 845-6886 FAX 10" thick by 10' long prefab polystyrene and concrete units can be cut into 15" by 15" blocks. End caps for wall openings. Entire wall is assembled and held in place with epoxy while steel reinforcing is positioned. Concrete poured into the core of units for entire wall at once forming an internal post-and-beam construction, flexible and strong. R-24 thermal insulation 53dB sound reduction Two hour fire rating by U.L. at 1920 degrees UBC compliance Does not wick water, but not water proof Stucco and tile can be directly applied to the wall Pest-proof Structural strength of a 5-3/8" poured wall 86% recycled, post-consumer, polystyrene by volume Construction costs equivalent to 6" stud frame construction. Engineer must be consulted for three story structures or over. InSteel Construction Systems, Inc. 2610 Sidney Lanier Drive Brunswick, GA 31525 (912) 264-3772 Phone (800) 545-3181 Phone (912) 264-3774 FAX Panels of polystyrene and steel mesh 4' wide by reasonable length in 8" increments, can be cut in field. Final construction is two layers of Shotcrete (sprayed on) surrounding core of polystyrene forming a "space frame" Made from recycled steel (not from recycled polystyrene) CABO 1 and 2 story dwelling compliance HUD compliance Excellent thermal and sound barrier (no specifics given) Excellent thermal mass characteristics. Structural Insulated Panel Association 1511 K. Street, NW Suite 600 Washington, DC 20005 (202) 347-7800 See also Progressive Architecture, Nov. 1993 A specific mfgr: Better Building Systems 418 Broad Street Nevada City, CA 95959 (800) 200-2794 Phone (916) 265-2794 Phone (916) 265-9349 Fax The general beast is a stressed panel of wood, sometimes made of post manufacturing byproducts adhered to a core of insulating material like polystyrene or expanded polystyrene. Thickness vary. Units usually ordered pre-cut for wall openings R-24 to R-35 More costly than traditional building methods Good load bearing and shear strength. Good for roofs because it spans well requires fewer joists. Steel framing is also considered an alternative building material and its popluarity is growing rapidly because of the easy with which it can replace traditional "stick" framing methods. I personally have strong reservations because of the very poor thermal charactericstics which must be mitigated with external thermal sheathing thereby greatly increasing the cost and complications in construction. From the Calif. Energy Commission: New 1995 Residential Standards Steel frame structures must show equivalence to wood frame structures for meeting mandatory envelope (floor, walls, roof/ceiling) insulation requirements. (This is a clarification of intent for those CA builders who don't care about having livable homes). Table B-2: Framed wall assembly R-values Framing Type Cavity Sheathing Wood Frame Metal R-Value R-Value U-Value U-Value 2x4 @ 16" O.C. R-11 -none- 10.8 3.46 R-11 8 18.8 13.3 2x4 @ 16" O.C. R-13 -none- 11.9 5.50 R-13 2 13.8 7.46 R-13 4 15.8 9.52 R-13 6 17.9 11.5 . R-13 8 20.8 13.5 The table continues, but I think this makes it pretty clear. I could think of no better way to throw away insulation than by building a building with steel studs. Don't believe a steel framing salesperson. There are very few bona-fide tests showing any methods of insulating steel studs that match the insulative value of wood studs. The last alternative is called "Engineered wall framing" system (EWF) and was tested by PG&E's Research and Developmnt department under the ACT Squared project. With this method, "Oriented Strand Wood" products replace timber as the main structural building member. Oriented Strand wood is made from pieces of wood cut from small, fast-growing trees and other wood milling by-products. The wood is stripped, embued with polyurethane resin and press formed into sheets up to 35 feet long, 5-1/2" thick and 8 feet wide. It can then be sawed into narrow boards. These OSW boards are much stronger than timber and a modified framing systems reduce the thermal conductivity of the wall construction by reducing the area of conductive paths through the non-insulated parts of the wall. A traditional timber stud wall has 35% wood/wall ratio while the EWF wall has only a 9% wood/wall ratio. The method also requires less material due to increased spacing between vertical members and the ability to omit a double-top plate which offsets the higher price of OSW. It does not shrink or warp. Some argue that steel stud walls, to be thermally competitive with wood stud walls, need to be built in a similar manner. The problem with either OSW or Steel stud engineered walls is that contractors are affraid of these new methods and building inspectors aren't going to know anything about them either. If it isn't obvious, I'm quite excited about the Integrid product I mentioned first. No other alternative building products have the U.L. fire rating. None match the structural strengh (except perhaps Insteel). The product has been used in Europe for a number of years. Contractors and inspectors are more apt to accept Integrid becasue of its similarity to traditional CMU (Concrete Masonry Units). I met with the president today and I think he has a great product. I am, however, in no way affiliated with them. These are my own opinions and do not represent an endorsement or reccommendation of these products by me or my employer. -Chas chas [at] innernet.com
- (no other messages in thread)
Results generated by Tiger Technologies Web hosting using MHonArc.