After all those years I was finally called on clip (H2.5) placement by an inspector.
I haven’t yet run it by the engineer but the inspector insists that the clip should be on the inside of the frame rather than the outside, because there’s more meat left on the inside after the birdsmouth cut.
The pictures on the front cover of the Simpson catalog and the illustrations on the product page shows the clip on the outside.
I always liked it on the outside because I hate those bumps in the drywall.
Any comments??
Replies
Have you ever noticed on realold homes where the rafter tail has split from the top of the birdsmouth all the way to the eave?
SamT
A rafter tail split from the top of the birdsmouth to the eave will not affect the holding power of the hurricane clip placed to the outside of the frame because the clips are fastened to the rafter above that point.
If the split were to continue toward the ridge then I would rather have the top part of the rafter held down, along with the sheathing, etc., than the bottom of the rafter as would be held down with the clip on the inside of the frame. Conceivably, enough force applied to the envelope could rupture a split rafter and cause separation, leaving only the bottom half of the rafter attached to the plates while the upper half of the rafter with the roof firmly attached, goes sailing off to parts unknown.
That split indicates the weakest part of the joist, the top of the BM and it (the weak point) runs both ways, also up towards the Ridge.
Now that I reread my post, I see where it looks like I agreed with the inspector. OOOPS!, Sorry. I'll be good.
SamT
consider predrilling and using screws on the upper rafter part to minimalize the splitting.
Be well
andy
In his first interview since the stroke, Ram Dass, 66, spoke with great difficulty about how his brush with death has changed his ideas about aging, and how the recent loss of two old friends, Timothy Leary and Allen Ginsberg, has convinced him that now, more than ever, is the time to ``Be Here Now.''
http://CLIFFORDRENOVATIONS.COM
I think they should be on the outside.
I don't know how it is everywhere in the country, but around here virtually EVERY house has OSB on the outside of the walls. It makes sense to me to put the clips on the outside, where the OSB holds the top plates on.
If you put the clips on the inside, it would be possible for the clips to pull the top plates off the studs (at least partially) since there's nothing holding them down except nails driven into the end grain of the studs.
They never open their mouths without subtracting from the sum of human knowledge [Thomas Brackett Reed]
Ron
Great response, I never thought about that....thats using yer noodle!
Be well
andy
In his first interview since the stroke, Ram Dass, 66, spoke with great difficulty about how his brush with death has changed his ideas about aging, and how the recent loss of two old friends, Timothy Leary and Allen Ginsberg, has convinced him that now, more than ever, is the time to ``Be Here Now.''
http://CLIFFORDRENOVATIONS.COM
The obvious answer is to install clips on both the inside and the outside, and predrill all the holes...and never mind what it does to efficiency.
Do it right, or do it twice.
I think your way is better, for above mentioned reasons. But you know how it is with some of these inspectory - "Do as I say, and don't ask questions."
Ralph brought up a good point about simpson showing them on the outside as it clearly shows on the link that I will post.
For all these years I've never seen them on the ouitside befor and I've always installed them on the inside and seen everyone else install them on the inside.
Now if simpson is showing them on the outside, I would assume all architects, engineers and these confused inspectors should check into it and SPECIFY THE CORRECT INSTALLATION OF THESE CLIPS ON THE PLANS.
What about the Overcut we all make in the birdsmouths on the rafters and take in considerations the lose in the rafter do to the H.A.P. cut (Height Above Plate). This is all on the outside where they show the Hurricane Tie to be nailed. Thetre's alot less meat on the rafter there.
Now on the inside of the rafter, the interior wall, you still have the full thickness of the rafter to nail the Hurricane Tie too.
Does all this matter? Now I'm curious and I will definitely ask the Architect this Monday or Tuesday when I see him.
http://www.strongtie.com/products/connectors_list/h.html
Joe Carola
Edited 8/24/2003 11:18:17 AM ET by Framer
Joe,
Good post. I've wondered about this as well. We (and everyone around here) installs them on the inside of the walls. I was just reading an article in Professional Builder about the hurricane clips during hurricane Andrew. The article stated that the hurricane clips had a 92% success rate. Now what I want to know is, where were they nailed. I bet they were on the inside, but I'm really curious. The reason I say inside is that about 2 years ago, we subbed the framing on a house next to the one we were framing and this framer frames in Florida when he isn't up here (his family is up here). He put the clips on the inside. I know that isn't very scientific, but I assume that other framers in Florida install them the same way. He also said that every nail used had to be stainless steel if you were within a certain distance from the water.
By the way, are you using a CAD program now? What kind and how do you like it?
One other thing, I'm glad someone mentioned that on older homes the rafters are split near the tails. One guy I work with insists on cutting the rafters in such a way that the tails are sitting on the corner of th plates. That takes a huge chunk out of the rafter. Anyway, we don't do it that way anymore and he seems to get a little miffed about that. Long story, but our roofs are flatter than his ever were and we cut and stack them in half the time. No joke. Of course that is because of all the info from this forum and some others.
Edited 8/24/2003 12:15:57 PM ET by TIMUHLER
Weighing in one more time....
Taking into account the many posts regarding efficiency and speed in framing, it's my opinion that the practice of installing the clips on the inside has nothing to do with what is structually correct and everything to do with what is the fastest.
Standing on a short step ladder or pushing a bucket around on the floor deck is way easier and faster than pushing/carrying a tall step ladder around on the dirt, certainly faster than moving an extension ladder and probably faster and safer than walking the plate, nailing off always bent way over.
The same inspector didn't say a word on a previous job where I also placed all the clips to the outside. I still hate the bumps in the drywall that occur at every clip installed on the inside.
Pull out some of your old framing plans and see where the engineer, architect or draftsman placed the clips. I'll bet the boilerplate section shows the inside as the convention although Simpson shows the opposite.
I'm not sure the point about hurricane andrew and the 92% success rate had anything to do with where the ties are installed. If I'm not mistaken, the vast majority of houses down ther are block walls with a 2X8 plate on top. So where the tie is wouldn't make any difference in that case.
Somebody from Florida please let us know if this isn't the case.........Why do you sit there looking like an envelope without any address on it? [Mark Twain]
When I have a cathedral ceiling I'll lay out my birds mouth, let's say for a 2x4 wall the seat cut is 3-1/2" and the hap cut ia 8-1/2".
I'll add another 2x4 to the top plate and take that 1-1/2 x 3-1/2 notch out of the birds mouth going up the hap cut.
Now you have a 7" hap cut and your rafter on the inside has 1-1/2" notch in it and that keeps everything in plane, doesn't change anything.
What this does is clicks the rafter onto the added 2x4 and locks it into place. the rafter can't slide off the plate, it has no where to go.
So if you have a 24' 2x12 rafter, the guy at the bottom can just lock the rafter right in and the guy at the top doesn't have to struggle pulling the rafter up until the bottom guy can nail it.
When I set up my rafter pattern I nail a block on the bottom so that any variation in the size of the rafters wont show up in the ceiling, you'll have nice straight sheetrock lines.
The rafter holds itself into place and it has no where to go. Doing ot this way you don't need any knid of rafter tie. I've been doing it this way for 20 years and never once had an inspector fail it or tell me to put some kind of rafter tie.
You have to be careful when it comes to using 2x6 walls and the steeper the pitch because you don't want to take to much out of the rafter.
This one Architect never seen it done like that befor and he liked it and told me he was going to draw it like that on the rest of his plans. About two years after that job I had to bid another job and sure enough it was his plans and he drew it just like the way I frame it.
Joe Carola
Joe, that's a great idea. Accurate cutting and positive placement with out straining the groin to hold it in place.
We would still have to strap it down for uplift.
The majority of framing here is with trusses. Those guys wouldn't have a clue how to build stick by stick.
I have to disagree with Framer's method of cutting rafters. That method reduces the load capacity by the amount that is removed from the rafter bottom plus the indeterminate amount lost by the stress riser created by that cut. In pre-sawmill homes and barns, where beam and log joists were half-lapped into top plates, the builders most always hewed the right angle completely away in an arc to minimize the stress riser.
Where to put hurricane clips in my opinion, depends on whether they are "required" or actually needed, and other factors such as who I am working for. When I was framing in the Fla keys, post Andrew, on those few stick framed roofs I did, I put them on the outside where they would do the most good. Most other places where they were "required", I put them wherever it was easiest and fastest.
Clampman
I like that detail . Never seen that done like that before.
It's not where the ties were places, it's WHETHER the ties were placed, as well as the rest of the components.
Seems that much of the structural failures could be traced to inadequate or downright shoddy and criminal building practices.
Post Andrew analysis showed that sheathing was tacked at the corners and the nail-off forgotten, clips were nailed to the top plate but not to the rafters or trusses, strap tie-downs were missing or just tacked, gable bracing was non-existant or lacking, lateral truss bracing was missing, staples rather than nails were used and many of them missed their mark or only one leg was embedded. Contributing factors included wind and rain gaining a foothold through thin siding and failed roofing, causing OSB to delaminate and break away from the fasteners. Once the wind got into the structure it didn't really matter if the sheathing was OSB or plywood.
CMU structures (the walls) remained standing but lost doors, windows and roofs because of inadequate fastenings in all aspects. No amount of strapping and bracing would have worked for some areas of damage. Mother Nature is much too violent and destructive to let little things man builds stand in her way. FHB had an article #78, Jan 1993, that was an overview of the damage and causes.
From Andrew came a knee jerk reaction that resulted in special Miami-Dade codes that have migrated into todays Florida Building Codes, including a complete book on Protocols for High Velocity Hurricane Zones. What we have now is a pain in the neck but results in better building practices throughout the state. My grandfather used to say if two nails won't hold it, then twelve won't either but then I don't think in his time and place there was the knowledge we now have or the products that contribute to failures or work to prevent failures such as caused by Andrew.
Boss,
My point was that if they had a high success rate, and they were installed on the inside, then the placement isn't an issue as much as using the correct nail sizes and making sure they are installed correctly. Obviously, if the clips were installed on the outside and had such a high success rate, then that would imply that maybe they should be installed on the outside.
All,
This thread brings up a good issue: namely, that there shouldn't be different opinions among framers, truss designers, code officials, etc. We should all be on the same page (or reasonably close). I would like to have an article or even a book that explains in a decent amount of detail, why we use metal connectors, how to properly use them, what happens when the proper nails aren't used, etc. It would be good reference and take some of the guesswork out of it.
One of the most irritating arguments for me to get into with other framers (on my jobsite at least) is about how this connector or that isn't needed or I can use this nail because I don't want to go to the truck and get a different one. How in the hell do I give an educated opinion when I haven't observed an earthquake or hurricane on a structure I built? Or if I haven't read the studies or taken classes or read about case studies.....
I don't have the training (or degrees) to understand the forces involved. Most of us in this field don't, but we all argue until we are blue in the face. I can't give an educated opinion about where these clips should be installed because I don't have the adequate understanding. I don't really think anyone else here does either. So we use the word "think" too often. Well I "think" it should go here because of "x" reason. The forces that result from an earthquake or hurricane aren't intuitive. We can apply some common sense, but none of us really understands the issues in their entirety.
For example, when we first started using foundation holddowns (HPAHDs and so on), our lead guy thought they were shear straps. He would use whatever scrap he had (4'2x6's nailed together) and nail the straps to these, then sheathe the wall and explain that this strap will help the shear strength. I was just working after school (junior high) so I didn't question it. He still doesn't like the idea that you have to have a post connected to the top plate and the bottom plate, nail that strap off with 16ds and then follow the shear nailing schedule. In fact he won't do it. He uses the word "think" too much. He doesn't "think" all this straps and shear walls and metal connectors are needed. How the hell does he know? Only recently has he seen the need to block the panel edges of the sheathing on shearwalls.
Sorry for the soapbox, this is an issue I get a little "miffed" over.
I'm going to email Simpson and if I get a reply, I'll post it here.
I've been doing some research on hurricane clips and here is what I found. Check the pic below. I apologize for the size, I couldn't reduce it and still read it.
Also here is the link from the page that I copied. http://www.strongtie.com/products/connectors_list/h.html
You raise some good, well thought-out points.
Simpson, and other manufacturers of metal connectors, along with engineers or architects who sometimes specify custom made ones are, from my perspective, the final authority on placement, fastener size, etc.
Simpson connectors have been lab tested BY Simpson for the forces the connectors are designed to resist.
It's our job to install them correctly and if an inspector has a problem with that, he should be challenged.
Hi Ralph
Took an interest in this thread as it deals with issues we face here down under. We use a version of the Simpson H16 tie except ours goes on the outside. We have very high wind loadings to meet . (for example, every truss/ rafter gets a tie plus a half inch rod plate to plate to connect the tie down )
with regard to the issue of bumps in the drywall from the ties. When I on the rare occasion fit a tie on the inside ( usually because of no tail on the rafter or truss ) what I do to eliminate this is have a coarse disc in my 4" angle grinder and hit the area where the straps are going to land. It takes a few seconds and allows the straps to stay below the wall plane.
regards
mark ( and Hi to Kathy )quittintime
Here in Florida the straps for trusses are much more substantial than h2.5. Typically the strap is one that wraps over the top chord of the truss and partially back down the other side. In this case splitting of the tail is not an issue.
For masonry construction an embed in the bond beam is standard ( HETA 20 )
For wood frame a twist strap that ties the top pl. to the truss is common ( MTS12 )
In addition, clips are required to connect, top pl to stud, stud to bottom pl, and bottom pl to slab. Or... forget the clips and go with a threaded rod system that goes from slab to top pl.
CARPEnter DIEM
I don't see where installing them on the inside (assuming rafters) is any better. Seems to me if they were nailed on the outside, the nails that go into the rafter are much higher up on the member. Better to have the nails farther up when you're holding something down. He loves nature in spite of what it did to him [Forrest Tucker]
In your drawing the red line now becomes the efective width of the rafter . Simular to a floor joist that has been cut on the bottom to fit in a smaller opening. Everything below the cut is easy to split off,if you lift on the outer edge of the stick.
I would want the clips on the outside of the wall as close to the top of the rafter as it can be.
I was hink the same thing before i got to the end here don.
As long as the seat cut doesn't hang over on the inside wall. i don't see how it matters. It is just keeping the rafter seated. But if you hang them on the inside with an improper seat cut . I think It will just leave the bottom half of the rafter.
I think the width of the the seat , along with the height of the birdsmouth, below the center line, Determines the actuall size of the rafter.
Just like a floor joist. if you have a 2 x 8 and you notch the bottom, even tho it is resting on the sill on both sides . it will still only be a 2 x ? ( what ever you notched it too.
This is one of the reasons i went with 2 x 8 rafters on my current project. Structurally, i could have done fine with 2 x 6. But i also want to pack it with R-30. but my rafters Are only 6' long.
Where there's A wheel there's a way, got any wheels?
Edited 8/24/2003 9:54:55 PM ET by MuleSkinner
Your statement "As long as the seat cut doesn't hang over on the inside wall."
You know that was the way I was taught to cut rafters. It just irks me because the guy that taught me to cut rafters (not cut roofs, but the rafters) still will argue that it isn't that big a deal to do it this way. I just get so mad. It violates good building practice at minimum.
I thought I would just vent. What do you say to a guy like that? Anyway, he won't help on the roofs anymore. That is fine by me.
Tim,
Who are you kidding, you never try to do the right thing............;-)
What's up Brutha?
Joe Carola
someone should e mail Simpson where ever they are and ask why/how they chose the outside installation method to use in the picture.
My experience with our county inspector regarding H-clips was that placement of the clip onto the face of the interior top-plate was suitable for both deflection and uplift. My inspector even checked the nail heads to make sure that the correct teko nails were being used so that they would not shear off. I would always place them on the inside because I would not have to risk going out on the ladder two stories up. This saves alot of time in labor not to mention eliminating the risk of having one of my guys get injured. If nailed properly, you shouldn't have a problem with "bulging" drywall." P.S save your fingers and buy yourself the Paslode Teko nailer..... you'll be glad you did!
And Simpson says...
Edit= Sorry Bryce, I meant to ALL
SamT
Edited 8/25/2003 5:24:37 PM ET by SamT
Sam,
If you look 6) at the simpson page you got all those pics from, you'll see that they should be installed outside if a continuous load path is require. http://forums.taunton.com/n/mb/at.asp?webtag=tp-breaktime&at=%2Ftp%2Dbreaktime%2Fgeneral%2Fdocs%2F836E29EA%2DE267%2D4CAA%2D89FC%2DB68E7CEAB69E%2Funtitled2%2Ejpg&frames=no
What that means is that basically if it isn't called out on your plans as a shear wall detail from the mudsill to the rafter connection, you can put them on the inside.
I think that makes this particular issue cut and dry. This is part of the reason I keep a simpson catalog in the truck. The other reason is so I can figure out how to install them correctly.
Ralph,
Since people are posting pics, this how it is done in SE Wisconsin. BTW, the call 'em tornado clips here.
Aside from the added expense, which would be minimal, why not double up and put them on both sides. Just a thought, this is FINE Homebuilding right?
Jon
just out of curiosity, has anyone ever had to work back into a roof, which was only partially destroyed. thanks to hurricane clips. I bet you have to tear it all off, and start over. Might be beter if it came off in the first place. LOLWhere there's A wheel there's a way, got any wheels?
"Might be beter if it came off in the first place. LOL"
Mule,
Yeah, and slammed into the neighbors house. I remember driving down Dune road in West Hampton two days after Gloria hit. Houses with the most damage were the ones one the bay side, not the ocean side.
Jon