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Checked it out John and what was also said, was that they didn't know the long term effects and were testing now, for this.
Also noticed that they were reducing the structural aspects of the house in order to offset the cost of these new modifications.
Kinda like the big auto companies, building trikes instead of standard 4 wheel cars and saying that in the long run or 2000 years, the savings in the 1 less tire is going to offset the cost of building this new model. The question is will the consumer go for it.
*Gabe,I think they refer to it not as reducing structural aspects, rather value engineering: Only putting in what's needed, and as an added benefit, reducing the amount of thermal bridging.Steve
*Gabe,The day you meet Joe L will be the either the best or worst day of your building career...You're either gonna join us or swear denial of all our existence...J
*Sorry Jack, but it will be a non event. There's nothing to join.
*Then swear denial to the grave buddy....All for non (e)vents,J
*Fred,I'm starting to see the light at the end of the "venting/insulation tunnel" (hope its not the proverbial train). Assuming that I can convince my GC to stand behind our new house if we build without venting, what specific product and application method would you recommend for the house? I will push the GC to find a different insulation sub that subscribes to your methods. To refresh, the design is a 1 1/2 story with dormers and a cathedral ceiling. Should I spec drywall on the underside of the attic rafters, then stuff the bays with cellulose (is there a brand/supplier that you can point us to). Do we stuff the walls on both floors with the stuff? Please point me to a spec, or email me directly, with more details. Thank you in advance. BTW why don't you head out here for a weeks "vacation" on me, and direct the insulation effort. ;-)Larry
*Dear Fred,I think the picture is a scam. Show the same section with the rotten deck.
*Dear FredGuess I was right again!
*Gabe. In the early 1980s the requirement for bracing and exterior sheathing was deleted from the Canadian Building Code. As Patrick posted he was shocked to find this to be so. Canadian building scientist A.T. Hansen noted, "Although most wood framed buildings continue to be sheathed, this is primarily to permit rapid protection from the weather and, in the case of insulating sheathings, to reduce heat loss. TRADITION, however, is also considered to be a significant factor in retaining sheathing."(My emphasis). If one looks at a wall in isolation during racking tests, one concludes that sheathing is necessary. However, when one look at a wall as part of a system and now analyzez the loads on the wall one sees that the external sheathing is unncessary for structural integrity. Given the above, Lstiburek's use of non-structural RFBI as sheathing, is based on solid research and engineering, much of which was done by Canadian building scientists. It is hardly a reducing of the structural aspects of those houses.Nést ce pas? If building inspectors(any many builders) had anything to say about the Voyager, it never would have been built let alone fly non-stop around the world.Gene L.
*GeneTry and follow this, if you frame a wall, using common acceptable practises, it has a given structural integrity. Maybe that integrity is overkill, maybe not.(Every once in a while, Mother Nature reminds us that she can still knock them down.)If you take away every third stud, the structure may still stand up, BUT THERE HAS BEEN A REDUCTION IN THE STRUCTURAL INTEGRITY OF THE HOUSE.As long as it don't blow it will be fine, but I wouldn't build it that way. My clients don't pay the kind of money that they do to have design and build a house with missing studs to save money to pay for added insulation that isn't needed.You're not comparing yourself to Dick Rutan, are you?
*Hi Gabe,With a 24" o.c. roof, 24" o.c. walls might be stronger than 16" o.c.....IF the studs line up with the rafters. BTW anybody have problems with the vent chutes collapsing with DP cels?
*Gabe. Of course, and I agree that one disturbs the sructural integrity of the house by removing every third stud. Full stop full period. However, if one engineers the removal of those studs as opposed to indiscriminately omitting them, then there is still a disturbance of the structural integrity. The question one now asks is: is it a difference that makes a difference?Don't you think the carpenters in 1832 Chicago were ready to tar and feather Augustine Taylor and George Washington Snow's new fangled Balloon Framing? One must be insane to forgo the existing 11th commandment framing for that balloon framing nonsense? No I do not compare myself to Dick Rutan. He designs aircraft I design houses. My point was that if you think competent structural engineers are crazy because they remove 41 percent of the framing lumber in a house--as did Frank Holtzclaw in his Arkansas House what would you think of Rutan if you knew how he constructed the Voyager?Take issue with those who copy without understanding the consequences of their actions. It is one thing to dislike lean and clean--to copy Count Bassie--framing. It is quite another to say here are the structural calculations to show it won't work. But then many structural engineers said of some of Frank LLyod Wright's structures, it won't work. YYes I know about the leaking roofs. GeneL.
*If Frank only had rubber roofs...J
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Fred ... when you say the f.g. wicks moisture to the roof deck, are you referring to the batts wicking indoor humidity upwards ? I presume this is same problem for batts in walls... don't contact f.g with sheathing of any type -- not just water wicking but also icing would become a problem.
If so, why can't the vapor problem be prevented in the same fashion as a wall ?
Doesn't cell insulation also wick moisture ?
Seems to me that sheathing the underside of the rafters is structural overkill and unnecessary expense. Why not stretch an inorganic fabric or even heavy duty poly across the rafters for the same functionality (ie; creating the insulation cavity). If you want a rigid seat for the insulation, why not use foam board with battens and kill a couple of birds with one stone.
Where is the vapor retarder in this picture ? If infiltration transports that much more moisture than diffusion, won't the joints in this indoors roof plane actually make the interior moisture penetration and insulation saturation problem even worse ?
Tedd
*Actually, Frank built a lot of flat roofs, commercial and residential. I wonder what he sealed them with.Tedd
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Gene,
Let me start by saying I know how Rutan built his plane. When the multi-nationals were all using state of the art equipment, thousands of engineers and draftmen, hundreds of millions of dollars spent on theories, he had to rely on what he knew, on common sense and on a early MacIntosh computer. He won by working with nature, not trying to harness it.
With regards to Frank Lloyd (the seive)Wright's structures, enough said.
With regards to removing all those odd pieces of lumber, NOT IN MY HOUSES....
Skyscrapers are conceived by Architects, designed by Engineers, and can be built by high school dropouts.
Building is only as complicated as you make it.
*Most likely built up leaky asphalt...J
*Probably built up with coal tar - which use to last a long time and was somewhat self sealing - as one post suggested it actually softened in the summer and this resulted in resealing. As I understand it from a roofing expert, over the last several decades or so, the refineries were able to extract even more salable goodies from the petroleum and what was left was weaker and less flexible and basically more impurites. Thus, failures came sooner.But rubber roofing also isn't forever. I'm actually seeing more big buildings that I've worked on going back to built up roofings based on some improvement in the bitumin.
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Coal tar ! Mighty toxic stuff ... maybe that was Frank's downfall ... his clients didn't last long enough to rave up his ideas.
*I always understood the stack effect to be a function of infiltration from the bottom and exfiltration at the top in conjunction with natural convection causing a draft. I presumed stack effect would be virtually eliminated if the building were airtight. Sounds, by what your saying, that the stack effect is significant even in a well sealed building - warm rising air putting pressure on roof and trying to suck in air from the walls below - smothering the occupants I suppose :-).Being that this is the case, why not vent the walls into the building envelope intentionally, drop the walls' VDR and, instead, seal the exterior walls against external moisture penetration, solar drive; etc. Then rely on the ventilation system to establish desirable relative humidity -- thereby wall cavitiies and frame moisture levels would be kept at same RH as interior environment. From what you and some others are saying -- and I don't yet have a handle on the principles -- the dense packing of cellulose insulation is filling the rafter bays so tightly, that vapor cannot find the medium or environment for condensing out of the air and will therefore not wet the surface of the roof sheathing and framing. Is this no-condensation-on-structure a function only of the "electrostatic" and molecular properties of the cellulose or is it because the realtive reduction of the open air space adjacent to the framing members and sheathing ? In other words, are you saying that one must not just use cellulose but also that the cellulose must be densely packed into the cavity ?I guess its full circle time for me. If I use a dehumidifying ERV with a network of ducts, why use a VDR anywhere (poly, paint, sealed sheatings, taping; or what ever). Why not just insulate the heck out the place with high density cellulose, seal the building from external moisture penetration and rest on the ventilation system to handle humidity ? Provided I can keep my heated interior air from reaching the outside of the wall and roof cavities (which I gather the high density cellulose can accomplish).Tedd
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tedd,
outside metalized foam taped, studs with DP cels and no poly is what I am leaning toward...exactly as you state for why you state....And with less framing lumber which Gene likes...I also think SIP's are great (much less labor) if the price were right.
J
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Is this paradigm shifting time or what ... !!!
Why not use structural pulins on the the roof, eliminate the roof deck sheathing altogether, use XPS or similar foam, properly taped and run across the rafters/between the purlins.
Then use galvalume or steel roof. The purlins could be sized to optimize the air space between the foam and the steel for continuous venting. The DP cellulose could be installed up tight to the foam board. If someone wanted, they could structurally sheath the underside of the rafters and use this plane as a floor for the bays to hold the cellulose.
This wouldn't be needed structurally so wall board would work with ADA or poly if one felt it (vapor diffusion barrier) was required.
If horizontal - instead of vertical vent channels is the objection to this proposal -- recess the foam board with top ledger stirps running along the inside of the rafters. This will give a vertical (soffit to ridge) channel.
*Gabe ... I'm going the other direction from you on this. That's why I proposed dropping all wall sheathing. Diagonal bracing and cross bracing can do the trick. Pole frame construction is based on these principles and so are high rises :-).Tedd
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Tedd
I do something like you propose all the time on my roofs, which I typically cover with galvalume. See < Obsolete Link > Patrick M. "Vent chutes in a cathedral ceiling" 3/19/99 10:18pm. I don't work with cells yet, and install the vent shutes below and perpendicular to the purlins to provide
i cross ventilation.
and to make install. of the roofing easier (roof ladder).
*tedd - "Seems to me that sheathing the underside of the rafters is structural overkill and unnecessary expense."There are no absolutes in your statement, so I can't fault you for that. What about old roofs (like mine) framed with 2 x 4's! Is that CDX or OSB on the inside structural overkill now? Or....is it a way to make the best out of a bad situation.It's interesting that you picked this out, because I was just going to look into sheathing both sides as a means of reducing framing size. Just a curiosity at this point.-Rob
*I was in my attic last week contemplating same issue. I am furring down 2X4 rafters with 2X3's, will cover with 1.5" polyiso, and blow cells behind. But I have some long spans of 2X4's - nearly 16' - so am sistering 2X6's and will carefully glue and fasten 1/2" ply to the 2X6's with ply fastened and joined per APA specs for stressed skin panels (1 - 8' pc center span and 2 - 4' pieces at ends with a 2' pc for 1' overlap at each joint - all glued.) I believe this will be a little better than a 2X8 strength wise. I can then cut a hole in the ply without much effect and still blow cells into cavity.I figure that 2X4's have been fine for nearly 100 years and that the added weight of insulation and t&g finish on underside will not affect it adversely; t&g doesn't have the deflection limits of drywall; and I tore off 3 layers of roofing a few years back and added 1/2" ply on top, well secured.
*Gene,Did you see the story in the NYT about the concrete beams for the huge cantilievered projection at Fallingwater failing. Seems Wright cheaped out on the rebar. His GC tried to put more in behind Wright's back, and Wright got furious. The cantiliever has sagged seven (in think) inches. Now it's propped up on temp beams and they are retofitting rebar by drilling long holes through the beams and epoxying rebar into them.But I agree with you about value engineering. That's the difference between rational analysis and irrational ego.Steve
*Tedd,You're theory is based on the premise that we have too much waste in materials on the average site.Mine is based on the knowledge that construction has to be idiot proof as much as possible.This simplified house building 101 is another one of these here today gone tomorrow ideas.Anyone who thinks that you can mass produce houses, remove every 3rd stud, install single plates, cut out the exterior sheeting and replace it with insulation, install 2 studs in the corners and hold the whole thing together with clips and caulking is nuts.You picture a house 32 feet by 50 feet build this way. Now picture yourself walking on top of the walls to install the trusses, (which is an all too common practice)Your weight alone would loosen all the connections.Not much difference in this theory and one where you remove every 3rd rope on a parachute to save weight and space. The calculations that it would still handle a 175 lb soldier with a box of cornflakes would do little to comfort the widow of a 175 lb soldier with a box of cornflakes who made the mistake of bringing a quart of milk with him.Houses are designed and built to a standard of safety that is based on 100 year climatic experiences plus an added safety margin.You build what you want for yourself, but what you build for others is not yours. It belongs to your client. He deserves to have the best available, not what you think you can get away with.
*Steve,Not fair to point out rebar failure as being similar to Gene's suggestions...Rebar in structual concrete is failing nationwide and there were millions of engineers, inspectors, and contractors involved...Turns out all was based on bad science...Water gets into everything....Joe L on the other hand gets paid big dollars to tell people this and help them understand how there caulks and "seals" are much of the time the number one fault in there building system...b Science..."Capilary" loves caulk, because the gap still exists, it's just smaller...kinda like a roach hotel or lobster pot...one way in and no way out.The Status Quo, Has Gotta Go,Jack
*Interesting concept Jack, but the main causes of structural failure of rebar are; either it was poorly installed, it was improperly designed, (standard rebar vs epoxy) or last but not least, the building or structure (bridge) was not maintained.I have demolished rather large buildings that were well aged and I can assure you the rebar held up quiet well. It kept the hoe rams busy for a longer period of time then they would have liked.
*Gabe,You and I are on different planets...or you are twenty years in my past somehow...Epoxy rebar has been found to hold moisture that much better than uncoated rebar...And the rebar rots even faster sometimes!!!...All over NY, every bridge is being replaced and it's not that they weren't built perfect, it's that perfect is rediculously difficult to achieve with a normal budget and humans doing the work....Rebar used in concrete where the concrete is wetted often is d*mn difficult to make work period.I suppose you are one of those that still thinks the EIFS debacle is the fault of the installers and not just horribly bad use of materials and total disregard of basic science and capillary action...Never are we going to agree as far as moisture, capillary, and effects of "almost sealing" is concerned as it relates to building systems...Agreeing to disagree forever, thank you.On The Mountain Near The Stream,JIn the year of 1999,
*Jack look over your shoulder and I bet you can't see me. It's because I'm way ahead of the pack and I make my living staying there.Besides Jack, quality in building will never go out of style.And don't forget that the reason your bridges are in such bad shape, isn't because of the rebar, it's the lack of funding to maintain them. Same as here, the government took the money from gasoline taxes that was to go for road and bridge repairs and/or replacement and used it to pay off their pensions and election promises.
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Gabe ... I can't resist this.
You have not addresses the diagonal and cross bracing proposals that I outlined above and in more detail on another string about stopping the overbuilding.
Square connections and right angles of dimensional lumber butted against other dimensional lumber are hardly engineered or reliable structurally. Traditional stick framing is an evolution, not an engineered solution. We learned it from our daddies who learned it from theirs. Its light construction, easy to do, code entrenched and the manufacturing and foresty industries have forced it upon us. THis doesn't make it the best design structurally nor the fastest and most cost-effective means to build a house.
Since you say you want strength, look into pole framing and cross and diagonal bracing. I DON'T MEAN TRADITIONAL LET IN BRACING. You will find that triangular, curved and diagonal connections and planes are many tonnes of force stronger.
Why not incorporate some of this into your thinking and save your clients some money on studs and sheathing.
On todays building site, stick framing doesn't use studs to hold up the house, it uses studs to hold up sheathing. There are many stronger and less expensive ways to hold up a house. The laminate manufacturers and distributors benefit most from a trade that can't look beyond convention nor research the engineering literature.
Sorry ... I had to ventilate .. no offence. Seriously though, look into the the other structural options.
Tedd
*JackWhat are you recommending instead of caulk or what brand/type of caulk works. Tedd
*
Man. I'm with you on that awful eifs carp! Installation fault - funny thing that probably 95% is "installed wrong". Some system.
*Caulk is misused almost 100% of the time in residential construction...Scientifically one must remember that to get a perfect water tight seal on building materials that move and are porous just doesn't work...I am for back side drain planes and no caulk on siding for instance...No trapped lobsters and no hidden rot. The back side of anything that is caulked better be able to drain away what moisture gets in there faster than it goes in. Where I see caulk working, it is either only doing a cosmetic appearance function, there is no moisture problem or a seriously expensive caulk has been applied and it was applied to a very bondable surface like tile or glass, etc.Caulk is like diking to me...I'd rather not live below a water line,Near the stream but pleasantly warm and dry by my fire,J
*Bill,"Real user freindly!!!!"Banned in Carolina....100% banned.JGabe, You're a beleiver in the right caulk will do the job...Caulk all of Caralina so there EIFS is sealed 100% and you'll be richer than Bill Gates!!!...You'll never think of wasting your time on the other side of issues with me if you do...heck, you could by Taunton Publishing and ban us non-beleivers!!!Splashing water from the stream,J
*North Carolina - about a year ago I recall - hateful, ugly stuff too!
*Tedd,I'd be interested in your comments on the use of a single 2x for the top plate and the use of metal clips and plates to hold the corners and plates together.
*Whoa there JackThere is definitely places where the right caulking is the right stuff, but it's mostly cosmetic when used on the exterior sidings. You still can't beat a good rain screen like Tyvek.
*Gabe, I have used the single top plate method before. It works fine. You MUST line up the rafters/trusses within 3/4" of the studs. It is harder to line the walls. It is also harder to attach the top of the dry wall sheets. Splices in the plate are harder. Less thermal bridging. Pre-cut studs are too short. Inspectors have to look in their code book. Rafters and studs that line up with a single top plate is STRONGER than a double top plate where they don,t such as 24" o.c. roof with a 16" o.c. wall. I often mix single and double in the same house, other than 8' 0" walls or how straight the lumber is for the plate is often the deciding factor, but I slightly lean to the single plate because of cost, environmental conscience and thermal reasons.
*Bill - I have done this in 2 of 4 upstairs rooms so far and have never done the math. I can tell you that it feels heck of a lot sturdier under foot, or when pushing up. Asked an uniformed buddy to jump on the roof as a blind test - he agreed. I mainly did it so that I could hang drywall sheets and not worry about 14, 15, 16, 17" spacing of rafters.-Rob
*AJ,I know nothing about concrete and rebar other than you are in deep sh*t if you try to make a structural concrete beam without rebar. I just thought the story was interesting in the context of where the thread was going. So what should one do instead of rebar?I try always to build in ways that don't depend on sealants or adhesives as far as moisture control is concerned. I've never seen a caulk joint that I liked. Not that I'm not forced to lay one down every now and then, I just assume it's always a temporary thing. I always warn clients about the necessity to maintain caulk joints. I never use it for siding.Steve
*Gabe,I would take 24" o.c., 2 stud corners with drywall clips and a single top plate and full osb sheathing over double top plates and even 12" o.c. with foam sheathing and ply or OSB only in the corners. The joist/rafter lining up with the studs is MUCH more important for strength than wheather the plate is single or double. If they line up you could us a 1x for the plate untill the drywall subs shot you (ba-da-boom). More lumber isn't allways best for strength or thermally. But the "old" way is often the best with an inexperienced crew. I have had my share of "idiots".
*Steve,The first non-steel bridge is being built now or in the near future...carbon steal rerod rusts. the alternatives are flying out of my homebuilt aircraft pages...aramid fibers, kevlar, graphite,...carbon is still used but now it's pretty well known that until they can learn how to keep it from rotting out, there's a lifetime limit involved...Like helicopters having to change main rotor bearings after x number of hours...Cooperstown time,J
*Ron,Now you are a man of the future....Bravo...Sign me too,J
*Gabe,If you put a post on top of a post, the load transfer is direct. If you offset the load form the post, you need to make sure that the "header" between the posts (in this case the top plate) needs to be sized for the span. Even with double top plates I align the load from rafters to studs to foundation. The double top plates are convenient for keeping the walls straight until the next platform is on top of them, and the drywall guys apreciate them, but there is no structural need for them if you align your loads.In a timber-frame house you concentrate the load on only a few properly sized posts spaced many feet apart. The rest is just infill. So too with platform construction. As long as each "post" (2x4 or 2x6 in this instance) is properly sized to bear its share of the the load, whether they are 16 inches or 24 inches apart is irrelevant, no? The space between is just infill. What is the compressive strength of a 2x4 that is braced against wracking or bowing with 4x8 panel sheathing? Enough to bear the load of a twenty-four inch wide section of house, I would wager.I've not used drywall clips yet, but plan to try them. If you are counting on the connection between the drywall corners for structural strength, clips or screws, you are nuts! I want to try the clips as a way to reduce the amount of cracking in the corners.Steve
*Hi Jack,Future heck, I have been building like this for about 20 years.Staying warm with 60 gal. of fuel oil, a wife and 3 "heater cats"
*
Rob - I don't know the answer. It depends, I believe on who well connected the compression and tension flanges are. By backing up the 2X4's with underside sheathing, you could stiffen it or you could add dead load and make it worse. 2X4's, sheathing and cross braces can be turned into long span box beams if joined correctly.
Tedd
*
Steve. no I did not catch the NY Times article on Wright's Falling Waters. Wright could be arrogant, but he very often made the structural engineers eat crow.
Let me quote tedd here: " Traditional stick framing is an evolution, not an engineered solution. We learned it from our daddies who learned it from theirs. Its light construction,
easy to do, code entrenched and the manufacturing and foresty industries have forced it upon us.
THis doesn't make it the best design structurally nor the fastest and most cost-effective means to
build a house." As an example of what tedd is talking about is the 1/360 deflection rulke. It is not based on engineering but on experience of plasters of howm uch aag the ceiling joists could trolerate before the plaster cracked. And asnother example is the let-ion corner wood bracing. It is based on experience not on engineering. the BOCA code Commentary recognizes this and cautions that the experience is not applicable in all situations.
As I reads Gabe's arguments I wonder why two story houses constructed with 2x3s are still standing. What keeps houses built with 1x4 studs and 1x8 floor joists from falling apart? Why all those houses with single top plates, two stud corners and Prest-On clips and 24"oc framing have not fallen down. Worse yet how can those 60 year old houses built with 2x2 exterior wall studs and 1 x 6 floor joists not have collapsed? And why is the 1725 Deerfield, Massachusetts built with stressed skin panels and no corner studs still standing? And why does California's UBC code allow the use of the Prest-On clips in single family residences? Are they not afraid that the houses will collapse because the third stud needed to nails the bejesus--according to Gabe and Jim Locke--out of the GWB? GeneL.
*Gene the only difference between yor methods and mine is that I use the code as a minimum requirement, whereas you look at the code as a "never to exceed" specification.We don't allow 1x anything studs and 1x anything joists, so it would be academic to discuss.I would NEVER frame an exterior wall with anything less than 16" centers. Call me crazy, but I have a thing about giving my clients the best that I can give them.Further to our ongoing discussion, the OBC subsection 9.19 clearly states ventilation must be provided to all roof or attic spaces. (rigid insulation being the only exception)
*Gene,What is amazing to me is the willingness of the trades to adopt techniques that will enable them to save mere pennies on the dollar at the time of construction, but ultimately fail bigtime (ie: EIFS, masonite siding), yet the complete reactionary knee-jerking opposition to things that actually make a difference in the quality of the structure. If Cells were easier and cheaper to install initially than other forms of insulation, I'ld wager they would be in widespread use.Steve
*GabeYou're correct about OBC sect. 9.19 specifying i rigidinsulation, however, do you know how they definei rigid ???Could 'dense pack cellulose' qualify???GeneLooks like you're correct about 'Glasclad'. . . seems it was taken out of production late last summer, and old stocks are now all but gone.-Patrick
*I think FG is more popular than Cells because of two reasons:1. Big Company Marketing2. It doesn't need a tool bigger than a utility knife to installI'll keep using Cells most of the time.
*Patrick, the OBC means rigid as in styrofoam sm or similar.
*Ron,You are 100% right about marketing muscle being the number one reason why fiberglass insulation is in Gabe's brain and skin...Call it "the pink panther affect"...Near the stream,Jack
*Jack,You're being presumptuous again, get out of the stream, you need oxygen, NOW!Absolutely every major product that we use is as a result of marketing. Take Gene's book, for example, he preaches like an evangelist that he knows it all.But we all know, Gene included, that he doesn't. And as a matter of fact, neither do you or I. Difference is, I comment for the sake of stating my opinion, Gene does it to sell his book. Someone will ask a question about the time of day and Gene will post a reply connecting it to something in his book and FredL will reconnected it to ventilation and then you will support both without a moment's thought.I've noticed one consistency in your posts. If you post ahead of Gene or FredL, you normally give a reasonable answer and you're focused. If you post after Gene or FredL, you never consider the original question again, only your support for the other two.Do you get kick backs for selling books or what?
*Jack - you forgot lungs!!What are the fg people gonna do when word gets out that it causes lung problems WORSE than the dread asbestos!! It'll be illegal in no time. Then fears of fiberglass contact and fiberglass in ground water will run amuck.8-) Kind of funny when you think about it, this knee-jerk reactionary stuff.-Rob
*
I think that the EIFS proplem is a good example for Gabe's argument. A designed system that when built well worked long enough to get approval and then failed under real conditions in the field. Any structural system can be cut back to the bare bones to reduce costs or increase energy efficiency but than it is dependant on proper construction techniques to make it stand and keep it that way. We all know what a problem that is already .I used to drive 65, now the speed limit is 65 I drive 75. Anyway I think wood stinks for exterior framing and I am building an Icf house near the stream with steel interior framing though I dont know what type of rafters I am going use, (structural trex perhaps) and dp cellulose. I think that you got to push and use the stuff you believe in. Evan though there is no long term evidence for dp cellulose in rafters I going to use it if I can get past the building inspector and my wife. (who happens to be more conservitive than Gabe)I figure I can't lose, 30 years from if my roof fails I may get newly discovered low oxygen, cellulose consuming, rafter chewing mold spore named after me. John
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Boys, boys, boys,
Fiberglass is the most marketed building product there ever was....No knee jerking and I follow no one ever. Get that straight if you get nothing else. I don't think fiberglass is bad for installers or for home use... I know it's overhyped with huge piles of money invested in TV commercial time and magazine ads and I also know other products probably are a better choice for me and most homes built in the USA.
Stop trying to attach me to anyone's coat tails or put words in my mouth...I can do all that myself thank you.
Near the stream,
J
*John, I'm not very familiar with metal framing in residential homes. Is there any special requirements regarding fire codes etc. in your area?
*Gabe. I admire you because you give a damn. I do not think you crazy because " [you] have a thing about giving[your] clients the best that [you] can give them." The difference between us might be compared to the difference between Russian rocket construction science and America's version of that. Russian contruction was excessively redundant to the point of unnecessary costly overkill. We, om the other hand engineered our construction techniques and followed Ockhm's Razor.Yes we had our fudge factors but within reason, not m ore is better. I admired Frank Holtzclaw because he was willing to challenge 11th commandment framing. Using Value Engineering he eliminated everything that added cost, but did not contribute to the STRUCTURAL INTEGRITY,SAFETY,comfort and energy performance of the structure. His design provided a safety factor in excess of 2:1 for load and racking even though the house had 41 percent less framing lumber in the exterior walls than the typical house of the times.By the bye. This is the origin of many of the "accursed" techniques you find so troublesome."We don't allow 1x anything studs and 1x anything joists, so it would be academic to discuss" I mentioned these "odd-ball" framing methods because I want to know why if they are so *bad* they still stnd. The 2x2 stud walls/1x8 floor joists houses are over 60, years old. We've had dangerous ice storms, structurally dangerous high winds during those years. Still, they stand. Indeed the building inspector who accidentaly chanced upon one of these houses in Massachusetts, was more amazed by the house's solidity than he was of the 2x2 studs.His comment was that this changed his mind about code framing. His courage is refreshing. I've always cautioned, spans and loads permitting, frame 24"oc.GeneL.
*Bye the way Gabe and all, For the record, I've always framed 16" OC with double top plates. I even double my rough sills and such. But my choice is not based on perceived structural need for it or even local practice. Many builders here frame 24" OC because the area is so depressed that they need to save a nickel whereverthey can.I frame this way because I am a one-man operation, and therefore I'm the one doing the sheetrocking and the trim work, and I like having more studs and fatter top plates to screw and nail to later on down the line. I also like the more solid feel to the interior wall surfaces that 16" OC gives.I think I'm going to give drywall clips a try because, as I said, I think it'll help solve a lot of cracking problems. I've been doing California corners for years, and may switch to two-stud corners on my next project.Steve
*Gene,if I wanted to build a house out of 2x2 and 1x8 joists, like yourself, it would be easy.By carefully specifying the right contributing factors, you could design and build a very strong and durable house.What the hard part would be, is to design it so that the average "this is good enough" minded builder, would be able to replicate in a consistent and safe manner. Let's not forget the weekend warrior, who with the help of his buddies decides to build his own castle, using "some" of the information contained and leave out one or two of the "contributing" factors, because one of the boys thought it was a waste of money to install.Once any good idea leaves your hands, it's for the taking and that includes misinterpretations.With regards to ice storms, last year we had a dandy out here and our power was off for 3 weeks. The damage that was done is still very much evident today and will be for decades. Highly engineered steel hydro towers, collapsed like toothpicks by the hundred. Wooden poles snapped like kindling by the 1000's and millions of trees were destroyed. Mother nature reminded us not to build for today but for tomorrow.
*View ImageNobody's looking guys, Why don't you just kiss and make up?
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Gabe -
It seems your differences w/ Gene, et al, regarding building techniques is based more in your line of thinking than the technical aspects of engineering and building. This is evidenced by your recognition that it is possible to build a house faster and stronger using Value Engineering techniques.
I applaud your concern for the health of the average builder and the weekend warrior. It is because of these people that we have codes. At the same time, they are your direct competitors - any money they make or save costs you money. Don't you think that if you utilized building techniques that were faster, cheaper and stronger than conventional, you would reduce their ability to compete?
In the '80s the western car manufacturers got killed by the Japanese because Detroit built cars that were "good enough". This is not to say that Detroit got killed solely because Japanese quality was better (which it was) but more importantly the Japanese did it more cost efficiently.
Let me paraphrase a conversation during this time between an American and Japanese executive:
American: "Don't you think that once we have achieved 98% efficiency that there isn't a whole lot more we can do?"
Japanese: "That's where we win and you lose."
The point being that if you condone even the smallest amount of inefficiencies, you condone waste. The Japanese (eastern) thinking was that you need to continually improve the product and the process. Often, production contracts are structured to require the supplier to begin reducing their prices after the first year. It is for this reason that certain industries have become deflationary in the last ten years. There is no reason to assume yours cannot as well. There is a great book called "The Goal", by Eli Goldratt which addresses many if these issues. One of his points is that often, innovations are right there in front of you, but that common sense is masked by common practice.
This new line of thinking is a paradigm shift that has hit many industries. I believe you would do well to consider it.
-Lee
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Steve,
I think you will find drywall clips a one of those things where less IS better. You might need one less Heater Cat on a cold evening too.
Ron,
BTW good luck in finding the clips.
*LeeDon't confuse value engineering for construction experimentation.Those that cut corners (shoddy builders and weekend warriors) will never be in competition with me.The new wave of consumers for high end homes are baby boomers who; demand quality and recognize it; are very informed; and don't want to have to adjust their lifestyle to their surroundings.Ma and Pa Kettle Construction Companies and the Jetson Construction Companies are not part of their list of who to call when you need a new home.When I design a home, it requires an incredible amount of interview time in order to determine, with accuracy, what the client REALLY would want in their home and life.My job is to be able to look at all options and cater them to the clients. A home should reflect the owner's personnal feelings,lifestyles and attitudes.Not the ego of the architect or designer or builder. The house is not paid for by them and not to be lived in by them, it belongs to the client.This is why, I do not support the cheapenning of the code to accommodate a few who want to build their way only.
*Lee,You have put my feelings into words..."common sense is masked by common practice."...I am the originol "learn to do it with out others influence" kind of guy. The reason's for my self reliance and I suspect most others like me is that I often have no readily available mentor to learn "common practice" from. First big leaps of mine literally were teaching myself to fly from a book and then building a hang glider and sticking a go cart motor on it and just aiming it toward the sky. That first flight I stayed up as long as I could learning how to ascend, descend, turn and make an approach; total time to learn it all was twenty minutes. Very intense and I wouldn't recommend to many others to go this route. And learned how to kayak including eskimo rolls the same way... My construction methods and thinkings have all had such an independent formulative path as well.Glad to you posted and will be looking into the book you mentioned. Have you read "The Web of Life" by Capra? Check it out.Nearer the stream,J
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Gabe -
I do not doubt that you are currently able to sell your services to high-end purchasers. This is a product differentiation strategy that has worked well for many companies - even Jaguar sold cars in the '80s. Please note, I am not suggesting your quality is as suspect. In fact, I am sure it is excellent, if based on nothing more than the passion for it exhibited in these threads.
The point I am trying to make is that you could improve your net revenues by both increasing your margins and increasing your sales. You have stated above: "… if I wanted to build a house out of 2x2 and 1x8 joists, like yourself, it would be easy. By carefully specifying the right contributing factors, you could design and build a very strong and durable house." Were you to do this in such a manner that it reduced your costs, you would be increasing your margin and the time spent to complete a project, thereby increasing the number of projects that could be completed in a give time frame.
I am not sure how this would be a cheapening of the code - if anything, alternative building techniques would require a more comprehensive understanding of the requirements. This is a barrier to entry for "Ma and Pa Kettle" and any other bucket shop construction companies. In the end, it would be good for you.
-Lee
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Lee
Two comments.
I said it would be easy for me to do, I didn't say it would be cheaper to do. On the contrary to make products do what is beyond their everyday capabilities is very time consuming and expensive. Before you argue this point further, go find me 2200 linear ft of 2 x 2 without a single knot and when you find them, compare the prices of them with regular 2 x 4s used in houses today, and let me know the results. Next we will need 1 x 8 T&G pine boards for the exterior sheating, followed by 1/2 thick lath material for the inside. Last but not least, we will need a qualified plasterer to do the minimum 3 coats to lock it all in. Get the first point.
When the houses in question were built, wages were a wee bit less than they are today. Therefore, calculate the cost of building a house at the turn of the century using 25.00 per hour and let me know the total.
When your done the above, you will understand what I said.
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Jack -
Email me your snail mail and we can trade. When you're done, we'll swap back.
Heading for the mountains,
-Lee
*Gabe - You're still missing the point. The 2X2's reference was to demonstate you have admitted that alternative building methods are acceptable. Once I got you to admit that, the next step was to demonstrate that unless you continue to search for innovations, your methods may become outdated without you recognizing it. Sure you can build houses for high net worth individuals now. What happens in five years when the greatest economic boom in recent history comes to an end and you are forced to compete based solely on price. Ad-Jack, Freddy Lu and Gene L will have been implementing their innovations for years (the ones learned here and at conferences) and you will still be using the same methods your father taught you.One more analogy - Who do you think invented the quartz watch? - The Swiss. But they spurned it saying it wasn't as good as their mechanical watches. Within 18 months, Texas Instruments began building and selling quartz watches that were more accurate than the mechanical watches at 10% of the price. All I am suggesting is that you continue trying to innovate. Have a good weekend.-Lee
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Steve and Ron. Call Prest-On at 800-323-1813 and ask them for name of nearest distributor of their clip in your area.Prest-On also has a video you might find interesting. It's free.
Stick with the Prest-On clip. The others (some of which are plastic) have to be nailed or attached to the studs. The Prest-On quickly snaps on to the board. As far as I know it is still the only gypsum board clip allowed in single family residences in California.
Once you look at the loading of corner studs you'll see why the third stud adds only cost to the house. And when you see that GWB attached to two different studs tears the paper because the two studs are moving in opposite directions, you'll better understand why the GWB corners must be "floated.".
By the bye.Sprayed-in PUR foam obviates the need for clips. GeneL.
*Lee,Email is on it's speedy path to you...Great idea as I enjoy loaning out my favorites to those that show interest.Headed to the ski mountains for a double birthday day of sunny spring skiing and trail side "iced cold ones" to enhance the experience.Near the stream,J
*Gene and all,I learned a great trick from the home that I live in now, built by a "speedy save money" kinda builder. He doesn't install any wood blocking for drywall. The drywallers used there scraps nailed in place for backers. No clips, and no wood nailers for the "blue framing crew" types...I have average drywall finish with very little loose paper in corners except for one which happens to have all wood backing because it's a beam. And I bet the drywallers had a lot less scrap to load out at the end of their job.Also, my home is framed completely 24 inch on center and has no noticable sags....I believe in building of the highest quality but also know that using way more wood in a frame, than my area needs, is just sales gimmickry and or unscientific ego driven "chest puffing" bull.Near the stream,J
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I am considering closed cell foam insulation in my attic renovation. I live in a 85 year old home that has 2x4 roof rafters that bear directly on the top plates making the introduction of soffit vents very difficult if not impossible. The limited depth to the 2x4 is also problematic for the introduction of batt insulation; even if I were to scab on a 2x2 the introduction of a baffle and 1 inch air gap would only allow for a R-21 batt. I am reluctant to believe the claims of the spray foam insulation manufacturers (i.e. no need to ventilate or introduce a vapor barrier) however; my problems would be solved if their claims are true. Can you please help me obtain the answers to these questions?
1. Is spray foam with out ventilation an acceptable insulation strategy in Wisconsin?
2. Is the foam sufficiently moisture resistant to prevent indoor humidity from reaching the dew point internal in the insulation?
3. Is there a potential problem with moisture migrating from the exterior and being trapped by the insulation leading to rot of the roof framing materials?
4. The manufacturers claim that the temperature difference between ventilated and unventillated roof is 2 - 4 degrees (I find this hard to believe), but they report the test in their literature; what do you think is the affect on shingle life?
5. Do you know any differences / preferences between the Icynene and Corobond manufactures of spray foam insulation?
6. Has FHB written an article on this subject? I am aware of the FHB issue #100 article which is excellent but dose not address the ventless application of spray foam.
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Building Science Consortium has built 100's of homes with unvented attics and after detailed analysis has achieved excellent energy savings results. What's your experience?
http://www.buildingscience.com/buildamerica.html
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Doug,
I have experience with Icynene but not Corobond. Do you have a web site for Corobond? Maybe we should start another thread and compare these to PUR.
Ron