*
4×12 headers certainly do reduce head scratching and labor, but “the bigger the lumber, the older the tree” still pertains. Environmentally-concious builders think about the source of their lumber, and attempt to build wholly, or predominantly, with second-growth material. 4×12 headers used throughout a building do not qualify as environmentally concious. Box beams with insulation inside, I-beams, or (as suggested below in another response) single 2-by members can substitute for 4×12. It’s actually a lot more fun to find creative solutions rather than fall back on “cave-man” carpentry.
And no, the cripple blocks are not necessary. Cripples, and studs, on layout will carry framing loads.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
From plumbing failures to environmental near disasters, OHJ staffers dish on our worst and best moments.
Featured Video
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
*
Makes me think about earthquakes, GACC.
*
Structurally, it's masonry that causes most of the life-threatening problems. Remember Turkey?
Wood's pretty good stuff.
*
Thats the way to do it make it clean and make prouduction .Thats how we do it on my crew ...why waste the time. We also at times use solid headders instaead for interiors it saves time yet cost the builder more...
*you can also use engered floor joist that are 3 1/2 as a headder . the do cost more than a regular 2x but man do they save time...you can run into problems when it comes to nailing off exterior trim due to the I formation
*
I was looking around over the weekend at several residential job sites here in Dallas that were in the framing stages. It seems that nobody uses cripple blocks any more. (This is the block above the header that lines up with the cripple, trimmer, buck, or whatever you want to call the stud or studs under the header of a rough opening. I was taught to always put the block in, but it seems that it is not done any more.
Do you guys do this or not? What do you think the pros and cons are of this small framing detail?
Ed. Williams
*Hey Ed,Down here it is still common practice to use the crippler. I do it, and every job I can remember looking at lately uses it too. I have, however, been seeing some really strange techniques being used on trac houses lately. I am wondering how the local inspectors are going to deal with some of the stuff (such as using a solid 2 x 4, and then 3 small pieces of 2 x 4 spaced out, and nailed to it, then covering all of it with plywood to look like it is a solid 4 x 4 - why not just use a damn 4 x 4 and forget about the extra labor? This is becoming popular on porch post work.)James DuHamel
*That's the way I was taught, too, Ed.But, here's a thought for you. Unless the plans call for a header height different (lower) than the width of the nominal 2x12, Those little cripples are not worth the time to measure, cut and install when you can just use the same header regardless of the span requirements. If the span only needs a 2x6 header, use a 2x12. If the max span in the house only requires a 2x8, use a 2x12 for everything. This ensures all headers line up and gives REALLY solid support over openings. This tidbit applies to all openings in a standard 8 ft framing. If the windows are to be framed higher than the door then reduce the header incrementally, until you reach the minimum allowable for maximum span (of the widest window). That keeps all the window heights lined up.In all other applications, higher ceilings, for instance, then go ahead and size the header and USE the cripples. Or, with higher ceilings the header height is also higher above the windows so the same 2x12 can be used for windows and just cripple the doors. You also don't have to keep/buy different stock for all different headers.I also like all that extra blocking for things like cabinets, towel bars, shelving...you can do that stuff when you don't have to work from other peoples specs.Comments? Ralph
*Ralph,Yes you are right..it is much easier to use the same header size throughout...this also eliminates the "Duh!!, I've put the wrong header in the wrong opening" comment.The extra cost of material is negligble compared to the labour cost of different size headers and trimmers.Defenitley block for fixtures.mark
*Ed, I was taught the same way you were and still do it that way. It just seems to help lock the opening frame together at the header whatever size it is. This is especially true on interior walls where the " header" might not be anything more then 2 2x4's nailed together .Vince
*Q: Why not put the header up against the top plate and forget the cripple? Then the top plate is evenly supported, and a sag in the header won't bind the opening. You will need to add a nailer below it usually...A problem with the big headers is energy efficiency. Does anyone use headers of just a single larger piece of 2x?
*4x12 headers certainly do reduce head scratching and labor, but "the bigger the lumber, the older the tree" still pertains. Environmentally-concious builders think about the source of their lumber, and attempt to build wholly, or predominantly, with second-growth material. 4x12 headers used throughout a building do not qualify as environmentally concious. Box beams with insulation inside, I-beams, or (as suggested below in another response) single 2-by members can substitute for 4x12. It's actually a lot more fun to find creative solutions rather than fall back on "cave-man" carpentry. And no, the cripple blocks are not necessary. Cripples, and studs, on layout will carry framing loads.
*Ah yes, what of 1/2" plywood box beams? I've been reluctant to try anything not common in the area already. A 9" deep box can replace a doubled 2x8, while preserving normal R-value.Practice here, outside of tract devs, is identical big headers over every opening, whether bearing or not. I share the concern for big old trees -- and the scarcity of decent wide lumber -- besides, the bigger built-up headers are just more work, more time, more money to make and install. I'm trying a single 2x6 in place of the recommended doubled 2x4's in a 2x6 wall supporting a Note that the CABO-recommended doubled headers ASSUME a 10-ft. tributary span above -- that is, a roughly 20-ft. wide house. A 5-foot span dormer roof and 14-foot span main roof impose very different loads (1:3), but the rule of thumb ignores this. By contrast, the section on plywood headers does include span-compensation info ... but omits the load above (roof only, 1 story, 2 stories)!Last thing -- anyone know if it makes a difference, and if it does how to compensate, that the loads from above are point loads (not evenly distributed over length of the header, rather focused at stud/rafter locations)?(... waiting for the rain to stop so I can go work on the roof ...)
*I still frame everything with cripple blocks. It makes for a solid, neat looking job. I size headers as needed for the corresponding loads and take care to keep window and door heights consistant.I am also committed to using environmentally responsible building practices. I have had great success using I-Joist floor systems, OSB subflooring and sheathing, and finger jointed 2x4 and 2x6 studs for walls.
*Doug!!!Thanks for your efforts. It's amazing how often you'll see a 2'0 closet door with a double 2x12 header. It's especially noteworthy when the wall is parallel to the joists overhead. Chase
*Regarding finger jointed studs... Does anyone know what the difference in tension strength is between ordinary stud material and finger joint? And, is it a factor in anyone's building engineering?Also, what additional uplift strapping might be required (if any) or is sheathing the primary or only means of preventing separation/failure of studs at the finger joint? I've never seen or used fingerjointed studs. Besides being advanced as environmentally responsible use of what would go to the scrap pile do they hold up in actual use, other than in vertical compression mode?
*Ralph-I've been using the finger jointed studs for about five years now. I can't honestly say that I know how they would perform in a tension application. My houses are all subsided with osb and I have never had an uplift question. It is a point well made and I have asked my supplier for input.If I have a point load causing uplift at the end of a beam I use metal strapping the length of the post continued to the floor joist/joists.I get straight walls using these studs, virtually no nail pops, and joints in trim stay tighter. The studs cost about a dime more each. None of my subs has any problems with the product. They complain more about the I-joist.I will forward structural info when I get it.Hubcap
*I don't understand why the practice of installing thei lintels ( 2 pcs of 2x on edge. . . headers as you yanks call em) directly under the top plate, regardless of the height of the door or window, means that these lintels then have to be oversized. . . they don't.I routinely install the correct size lintel directly under and attached to the top plate which provides excellent nailing and takes the potential i hingeout of the wall (especially taller walls). A header (2x on the flat) and cripples can then be installed as required. This also allows the crips to be a decent length and not such a pain in the butt to install.Haven't we done this dance before Andrew???-pm
*Ralph- I received a fax with design values for the finger-jointed studs. Kinda' hard to make out. Anyway, they meet or exceed all values for non jointed lumber of similar size for similar applications. Recognized and accepted by all major codes in the USA. I have found that they are more dimensionally stable and hence less problematic to frame with.I will get a better copy and forward to you.Hubcap
*Yep, at least the waltz you're taking. Nowadays, I'm curious about the sizing the HEADER relatibe not just to the span supported, but also the tributary load (joists or rafters above), and whether a single 2x can do the job.Call it intellectual exercise... nailing headers (ok, "lintels" -- here that means concrete or steel) is not very exciting work...
*AndrewThe proper sizing of lintels in bearing wallsb is all abouttaking into account the "tributary load"!!!Point load. . .what i real instance that wouldn't already be taken into account, or easily accommodated by going up one category (from single story plus roof load, to two stories plus roof, for example) Point load. .. single 2x. . . bad idea. Where in the width of the wall frame would you place this single so it did the appropriate job, and didn't contribute to shear along an edge? And, strictly hypothetically, what size single to do the job of the previous double.Intellectual excercise?? Nailing headers isn't exciting?? Seems like basic engineering and common sense to me!!-pm
*I'm just talking about alternatives to the doubled 2x12-fits-all.Point load -- for example, a big post in the center of the span.Single 2x's are fine by our code if "sufficient for all loads imposed." As for sizing, depth is a lot more important than thickness -- how much so I'm not sure.
*Andrew - If you have a point load from above, you need to analyze the header a lot differently than if it had a uniform load. I can't exactly tell you how, as I can't do it by hand. Generally what I do is cheat a bit. I design the header in a program written for LVL beams, and print out the results. The program gives me the maximum bending moment for the beam. Then I just compare that to the bending value for 2X12 (or whatever) to figure out what will work. The practice around here is about the same - double 2X12s over every door and window. There's sort of a running joke that "Two 2X12s will carry anything". They use 2X12s under gable walls in small window openings that probably need no header at all. Then they still use 2X12s in 16' garage door headers that are carrying 40' trusses. (Which doesn't even come close to working) They don't give any thought to what the header is actually carrying. I'm kinda fond of 3.5" by 11.25" insulated headers. Seems to be a good solution to most of those problems, and they cost about the same as a double 2X12 header, if you figure the cost of the labor to assemble them.
*Before anyone reminds me, I am going to run critical situations by an engineer first. Just like to know the possibilities. One reason I'[m interested in single, thinner headers is that I'd like to use a 1.75" LVL for a fairly heavily-loaded 6' header in a project soon.Ron -- 3.5x11.25 insulated header -- is that a preassembled unit?Ed, on the question you actually ASKED, I can't see what benefit a cripple (cripple = baby stud) over the header/trimmer could provide. Header at the top makes more sense anyway, or so it seems to my naive mind. Any cripple(s) below the header is really just a nailer & carries no load.
*Andrew - Yup - They're one piece. Check out: Superior Wood Systems
*I don't put those cripples in GACC. They actually don't do anything, but waste lumber. No one nails into them and they aren't really needed for support, assuming you've already placed a cripple under each joist above.For a while, we were framing our interior, non-bearing headers as a single 2x4, without any cripples. In an interior wall, with an eight foot ceiling, the space between the header and top plate is only 10". Since drywall can esily span 10", we reasoned that we didn't need these extra cripples. It worked fine, until some homeownere complained. I had to go back and put them in one house, for "customer satisfaction". Now, to avoid that I simply put a few in each header. Often I just put two, about 8" from the end. If it's a long header (48" or longer) I'll put a third in the middle.They are just a waste of resources, time and energy. And they will add up in time and eventually cost you the entire labor on one house. Figure it out: how many linial foot of ten inch cripples will you put in, in your lifetime if you frame every day for forty years?And don't forget to count the nails!blue
*What amazes me is when I dig into some of these old houses, built in the 20s and 30s and they don't have ANY headers over windows or doors, even on bearing walls. The sheathing (usually 1 x 6 shiplap) apparently provides enough sheer strength because the 2 x 4s over these openings are usually straight as arrows. Fact is, I don't think we take the diaphram strength of all that wall sheathing into account near enough. That adds a tremendous amount of strength to the building. Like, when remodeling, and enlarging the width of an opening in an interior bearing wall, use 1/2" MDO instead of drywall over that opening, nail the socks off of it, and tape it in just like drywall. Adequate in many cases and much less expensive than installing a header. We're header crazy in many cases (like headers over windows in gable walls) just because it looks right.
*Tex,I've run into that also. Old houses built back in the twenties or so that had no headers over exterior load bearing window openings.....just a 2x4 laid flat with one studlet in the middle. No cripples....just one king stud. 1x8 shiplap on the exterior and wood lathe for plaster on the interior. The funny thing is that it held up great for all these years and was hell to demo. Makes you think...doesn't it.Ed. Williams
*Here's my take,We do install the cripples next to the king stud primarily because some contractors and homeowners consider it to be part of a quality job. It is a lot of wasted effort, maybe 40 pairs on an average house. Alot of folks out there would be happy if a house was solid wood.My personal belief is that good framer will allocate his resources wisely in an effort to provide a quality job at or near the market price, while maximizing profits to himself. To that end, I would rather have my guys find straight king stud and cut a tight straight jack stud for underneath the header. Then take the time to properly nail it into the frame. I don't get to fussy about how the cripple above the jack looks. In eight foot walls I use double 2x10 headers bearing or not for single doors as it is faster in my system and eliminates the need for any cripples. By the way, why hasn't "cripple" been deemed poltically incorrect? We sometime use the term "pin" if the house is ADA compliant for example.Tom
*Yeah, then what's really embarrassing is when some old timer points that out and asks "...why are you adding that header? It looks fine to me..." and he is right on. Sure makes me wonder.
*Ouch Tommy! Your an owl killer!blue
*I got a great recipe for owl. It tasteses jus like chickin!
*So that's what they meant in Twin Peaks when they kept sayini "The owls are not what they seem."-pm