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Braces #4063 03/14/07 12:35 AM
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beerfreak Offline OP
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Why do braces seem to be fitted to the outside or inside of posts and beams rather than in the middle. I can understand if windows are to be fitted but this seems to be the norm.

Re: Braces #4064 03/14/07 01:29 AM
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I work with historic timberframes and it has been my experience that traditional jounery is based on laying out from the "Framing Face". i.e. braces are framed 1 1/2" & 1 1/2". Tie Beams can be 2" & 2" or 3" & 3" etc. Something to that affect. Why? It was my understaning that this was simply to make the layout process systematic and it would be easy to layout using just the Blade/Tongue of a framing square.

Funny thing is laying out from the "Framing Face" could mean the master builder used one of the following layout methods. Scribing, Snap Line Square rule, Square rule or Mill Rule.

PS

Re: Braces #4065 03/14/07 01:48 AM
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Beerfreak
I might be missing what you were asking but, the reason you reference to the outside face (on the outside of the frame) is so the siding has a smooth surface to be nailed to. If you centered them you would have to shim out to them.
On inside timbers it is so walls could be done the same way.
Bob

Re: Braces #4066 03/14/07 11:12 AM
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Like most, we do frame layout to an outside face, square rule for the most part, but than just 'flip' the inside braces to put them in the middle during assembly. We don’t do this all the time, but is an option. Braces on the outside bends look best to the outside and function best as well as they can be nailed to.
pete

Re: Braces #4067 03/14/07 11:38 AM
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Timbo Offline
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I to uderstood that in square rule the blade of the square was used for layout from the outer referense face. In scribe fit this face would have been hewn to a tighter tolerance probably using a square ir similar instrument.In heavy duty frames 4x4 braces where sometimes doubled up to on tying beams. I also concur that the brace on the out simplyfies and strengthens the joint considerably. If the brace was in the middle of a 10x10 for instance then the craftsman (or apren.) would have to bore a peg hole fully through beam.


Timothy W Longmore
Re: Braces #4068 03/14/07 11:56 AM
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but ...

there are plenty of other instances where the post must be drilled right through. To fit the girts to the outside face is toute apparent but why the need to fix (nail) to the braces when they (usually) cover but a small corner of a wall siding?

The marking up, I can see would be easier; I'm planning to fit my house braces central to the girts, then I can hang misteltoe & holly over them at Xmas! laugh


Time is an ocean but it stops at the shore Bob Dylan
Re: Braces #4069 03/14/07 12:11 PM
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Gabel Offline
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Beerfreak,

The short answer is that it is easier that way, especially when scribing -- which is how practically all English frames were built.

Also, as has been mentioned (and perhaps of greater influence), keeping the faces of the timbers aligned (posts, beams, braces, studs, etc.) allows for easier cladding, infilling, or partitioning.

Cheers,

Gabel

Re: Braces #4070 03/14/07 11:11 PM
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Thomas-in-Kentucky Offline
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From my limited experience, draw boring becomes harder to accomplish when your braces (and tenons in general) are toward the middle of your timbers. Any misalignment of the boring bit (deviation from 90 degrees) becomes amplified the further you bore into the timber. (and if your timbers are not exactly square, and historically they would not have been, then this is even more of an issue). Not sure if this is _why_ they held braces to the sides of the timbers, but this is one reason _why_not_ to hold them toward the middle. Of course this would not be a concern if you do not use draw boring.

-Thomas

Re: Braces #4071 03/14/07 11:17 PM
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E.H.Carpentry Offline
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I would have to agree with some of the previous postings. It simplifies layout, infill or clading etc.

With draw boring you drill the hole into the mortise first then mark your tenon. So it would not matter were you put the brace and wether or not the hole is a perfect 90 degress to the boring face.

Re: Braces #4072 03/15/07 12:41 AM
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We have run into many instances where the brace hole did not penetrate thru the beam. I am always pleased to find them all the way thru and sdjust my dis-assebly time accordingly. Removing a purlin or tying girt as there also known when it has been "blind pegged" is a real pain in the. When you have a whole building worth of parts laying in front of you identifcation of parts is a no brainer. With everything laid out from a common face is just logical , the evolution of framing at its best. The way these connection work with the siding make for an incredably strong wall systems.


Timothy W Longmore
Re: Braces #4073 03/15/07 05:34 PM
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E.H.,

Good point. I did my brace drawboring backasswards. I pre-made and pre-drilled all (140) of my braces, which then required very precise drilling of the mortise holes. Surely the way you describe it is the right way! Dooohhh!

-Thomas

Re: Braces #4074 03/15/07 11:57 PM
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Thomas,

well, I would get confused, too with that many braces and what to do first. Maybe you have had your friend "Bud" around one to many times? laugh

Enrico

Re: Braces #4075 03/16/07 12:30 AM
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beerfreak Offline OP
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I have decided to fit the braces in the centre [center] of the post and peg all the way through as the car port will be open,so walls or cladding do not apply.
I am looking at 6"x 2.5" braces curved and 30"x 30" from the corner of the post if you can visulise it,the height up to the wall beam is 8ft,do you think this size of brace will look in scale.

Re: Braces #4076 03/16/07 01:17 AM
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northern hewer Offline
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Hello all:

Here is my 2 cents worth on this subject which I have taught many times over the years.

The placement of the braces to the outside of the historic timberframes did not happen without a reason, the main one being that the braces are in true alignment with the tenons that are on the posts which the braces are pushing against.

The tenons on the upper and lower ends of the vertical posts are placed roughly 2.25" from the exterior surface of the rough hewn timbers, therefore the pushing and racking of the framework due to wind pressure, etc. necessitated that the braces be placed in direct alignment ie: layout of the brace mortises would be 2.25" from the outside surfaces.

As the building wracked under wind pressures if the braces were placed in the centre as suggested above then the vertical posts would want to twist putting unusual strain on the frame and could cause a joint failure by snapping a tenon, or causing the framework to weaken.

The only place that braces are allowed to be placed in the centre of posts is where the through tenons are themselves in the centre of the posts.

A good example of this type of central layout could be in the centre bays of say a driveshed or barn where the connecting girts span from side to side. One that most people might relate to is the large anchor beams in the Old world Dutch Barns where The huge Tusk tenon passes through the vertical posts (centred), and the braces following suit are placed right in alignment in the centre of the post.

I might add here that some timberframers always offset the tenons no matter where the girts were in the building, while other centred the tenons where they could. Historically though all the outside timbers, posts, and plates and braces had their tenons and mortises offset to the outside, usually 2" from the exterior surface.

I personally have never found braces that were placed out of alignment with the corresponding layout of the tenons on their matching vertical posts.

I hope this helps to explain why braces are placed where they are in historic, or for that matter in modern frames by professional, or historical tradesmen, and I might say by engineering firms drawing up on site plans for construction purposes.
NH

Re: Braces #4077 03/16/07 01:49 AM
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Hello again;

After posting the above reply, there are a few more items that need to be addressed,

--P Smith--I have no idea what you are trying to put forward in your post when you mention three different measurements, could you clarify what it is that you mean by them in relation to layout--thanks in advance.

--MTF--Braces were never meant to be nailed to because as the building wracked due to wind pressures the nails would loosen, break or even loosen the siding, braces were always meant to work freely inside the board cladding

--Timbo--When working on hewn surfaced timbers, and doing tayout, a square certainly was used but was placed on chalk lines snapped on the rough surfaces, these lines represented a theoretical flat surface, and at no time did the hewer prepare a special smoother surface at any location as you mention in your post. Hewn surfaces are just that, rough, and in many instances twisted and very uneven, even from the hands of a very skilled axe man.

--Finally I have this observation about pinning wall braces. Over the years of observations, hardly any braces in historic frames were ever pinned this being for obvious reasons, as the building wracked due to wind forces, the little that pins passing through the tenon on a corner brace could due, would be practically nill. In the first place the tenon on the end of a braces does not extend into the cavity of a mortise any great distance and surely not far enough to prevent tear out under the tremendous strain generated by the wracking action of the building. Pinning might even crack the side of the vertical post where the braces's seating is located.

I realize though that in modern frames pinning the braces's ends is an accepted habit for what ever reason escapes me other than the aesethic look, and the lack of seatings for the ends of the braces as seen in modern construction methods
NH

Re: Braces #4078 03/16/07 01:55 AM
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What NH said ! Thats it exactly , for spanning (or central spanning beams) braces are strongest if the mort. for the brace is centered in the post. I've run it in a lot of old buildings, braces centered. Curved braces sound cool. I did curved braces on several projects. I use dovetails for bracing whenever I can. I would not recommend them for most softwood apl., I use larch almost exclusivly for frames.


Timothy W Longmore
Re: Braces #4079 03/16/07 02:18 AM
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The reality in the field from personal observation is that braces are almost always nailed with siding. Wheather that significantly adds much strength I don't know. And in our area of up-state NY many commericial type tf the braces where pegged. I would agree however that for the reasons you just outlined they probably wouldn't be worth the effort. But upon dismantling the pegs where apx. 90% intact. This frame was a coal and ice building that survived the great Carthage (NY) which leveled the city. It is a surprisingly well designed structure. In responce to hew to tighter tolerences I use chalk while hewing and choose my reference face and orient the log and hew this face to tighter tolerences. I don't know how any one could know how everyone hewed a log in the past. I then use a dry line during layout. I was not classicly trained as a framer (or typist)so many techniques I figured out or researched on my own.


Timothy W Longmore
Re: Braces #4080 03/16/07 10:55 AM
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E.H.Carpentry Offline
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Hi all,

why would it matter if the braces are being pegged or not? There is and should never be that much movement in any frame that the pegged braces would tear out. If they did then in all likelyhood the frame is not strong enough and the braces would fall right out if they were not pegged.
And eventhough siding is not meant to further stiffen the frame it usually does anyway once nail to the frame.

Re: Braces #4081 03/16/07 11:34 AM
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E.H.Carpentry Offline
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Quote:
Originally posted by beerfreak:
I have decided to fit the braces in the centre [center] of the post and peg all the way through as the car port will be open,so walls or cladding do not apply.
I am looking at 6"x 2.5" braces curved and 30"x 30" from the corner of the post if you can visulise it,the height up to the wall beam is 8ft,do you think this size of brace will look in scale.
beerfreak,

wether the size will look to scale or not depends also on the size of all other timbers used. Say I am building it with 6x6 post I would use a 4x4 brace. Also the longer the brace the more it will stiffen the frame.
In trade school I remember being tought that a square cross section for posts and braces is always stronger than a rectangular one. And wise versa for beams and joists or rafters.
And yes, for your application centering the braces would look very nice.

Another thought: If the braces are not centered the forces will work unevenly on anything the brace will push against. It would eventually twist the post and beam. One can observe that on old frames a lot. The braces are to the exterior of the wall and so are the studs. The joists however are on the other side of the beam. The beam is always twisted and creates a hump in the floor above. If the beam would have been fully resting on the posts and studs below it would not have twisted like that.

Re: Braces #4082 03/16/07 02:04 PM
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NH
Good points. I believe that approach to TF worked well for the forefathers, but I’m not sure it would work today. If you are building non-code compliant buildings that would be fine, but unfortunately I do not believe that approach would support today’s building codes. For the most part, any code compliant frame will rely on a full shear wall (conventional framing/plywood), some shear resistance do to SSP, braces acting in both tension/compression or a combination of the above. I believe it would be difficult to design/engineer a stand alone TF that relies on braces acting in compression only. I know this point can be argued at length, but I do not believe it is feasible to design/build a standalone TF that does not include pegged braces or another lateral load carrying system. I know the TF’s the forefathers built are still standing, but it is getting increasing difficult to use that approach today.

I am not a true student of historic frames, but many/most that I have looked at included pegged braces. Actually, many of the ‘historic’ house frames that I have seen in southern NE I would classify as post and plank frames. These frames are lightly braced, certainly lightly braced by today’s standard, and relied on vertical oak siding boards for stiffness. There is no doubt that siding adds significant stiffness to a timber frame, how much is debatable. I try to take advantage of stiffness when available. If I’m nailing siding, or SSP’s, to the outside of the frame, I’m going to nail to the braces, as it does add stiffness. If I build a frame that was flexible enough such that the nails worked loss in the siding, I would stiffen it up.

Thanks,
Pete

Re: Braces #4083 03/16/07 02:10 PM
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Jim Rogers Online Confused
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If beerfreak's posts are planed timbers then the layout and cutting of the braces in the center of the posts will work, as he can measure the mortise depth and housing depth (if he's using one) off the surface. But if his timbers are rough sawn then centering brace mortises and housings in the post are difficult to measure and cut accurately.
And brace layout accuracy is important for the brace to truly work as it should to prevent racking of the frame caused by the wind.
I agree with NH's comments about off center tenons and the possibility of the post being twisted.
One solution would be to also center the post top tenon to whatever he is using for a plate.
Being an open car port he will have to be concerned about wind up lift and the posts will have to be properly secured to the foundation to prevent any movement due to up lift...
Jim Rogers


Whatever you do, have fun doing it!
Re: Braces #4084 03/17/07 01:28 AM
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What would be considered to pass shear test , the pegged/ brace itself , or the sheathing ? Also are there different code requirements for agr. buildings? Many old frames are converted for homes and almost all around here use compression braces exclusivly. As I posted earlier we only find it pegged braces in commercial type buildings. My opion is pegs for barns are redundent as nh outlined. But if thats whats required to pass code it would be good to know.


Timothy W Longmore
Re: Braces #4085 03/17/07 01:31 AM
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the rough sawn face is not a big deal if you lay out as if it is a hewn beam and cut a house for the brace pocket to be layed-out in.


Timothy W Longmore
Re: Braces #4086 03/17/07 01:19 PM
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Timbo,
My experience has been that a TF relying on compression braces only will not satisfy most building code lateral load requirements. That is wind loads up to 120mph on the coast and towards 100pmh inland, the larger the building, the larger the issue. Using vertical siding to augment the lateral load capacity is a debatable issue; many engineers are not willing to ‘assign’ any stiffness to vertical siding. Some engineers will provide ‘credit’ for SSP’s and most will accept the shear resistance of a pegged brace. Every engineer and timber framer will have a slightly different perspective on this issue, but it is an issue.

My perspective is to add stiffness to a frame when available. Pegging braces is something I’ve always done, I believe it stiffens a frame during assembly, erection and over the life of the frame. I understand that if a pegged brace tenon is asked to carry ‘too much tension’ it will fail. Actually, when frames are loaded to ‘failure’ that is the way they typically fail.

Dick Schmidt has written many excellent articles on this subject, below are some of his results.

Laterally Loaded Timber Frames 2 (March 2002)
Fully Pegged (white oak frame) Stiffness = 3270 (#/in)
Both Pegs Removed Stiffness = 623 (#/in)
The above is for a 2-story white oak frame, the results for a 1-story frame are not quite as dramatic

A very large increase in stiffness is achieved by adding SSP’s. There is not much data available for the increase in stiffness do to the addition of vertical siding, but there is a large increase. There is no data available for the added stiffness do to nailing the siding to the braces, but again there is some.

Read the articles and draw your own conclusions and than build what you are comfortable with and/or what your building inspector will allow!

Not sure why this thread went this far and my apologies to Beerfreak for contributing to the ‘off thread’ discussion.

Thanks,
pete

Re: Braces #4087 03/17/07 04:00 PM
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It is my understanding that braces are the primary members in any timber frame that allow it to resist racking. Most often from wind. To do this effectively braces are framed in tandem, opposing each other. Thus, when the wind blows on the north gable wall (bent 1) of a frame it would be the braces on the south gable wall (bent 4) under compression that resist the racking effect. Braces were sized and framed to work in compression. Wood is strongest under compression. There are exceptions to this rule but the over whelming majority are meant for compression not tension.

Pegged or non pegged braces. Nailed vs. nonnailed. tenoned vs. untenoned. It seems these demonstrate regional building styles as well as historical transitions. Braces that are nailed throughout a barn/home (often with wire nails) represent the transition between timber framing and "stick" framing.

Why peg the braces if it doesn't work in tension? Because it helps to square the frame up during and after raising. But there are examples of barns where the braces have only stub tenons (I'm thinking of a barn from Ontario I have worked on) I imagine the builder saying:

Forget this there are just two many braces
were not going to mortise out 4 1/4" just 2
1/4" and leave it at that. No need to peg
them, they won't fall out because as soon as
one loosens up the opposing ones "catch" them.

I would thing it would be an interesting study to look at braces, purlin systems, bent spacing, etc. to discover different regional differences. through out the U.S. Ovisouly my experance is with barns from the northeast.

P Smith

Re: Braces #4088 03/17/07 04:29 PM
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I do not beleive I have ever seen a pegged brace in an old barn in this area(central ontario). Or a brace tenon longer than 3". I have seen plenty of empty brace mortices.... some of the barns around here have only half their braces still in place.

Re: Braces #4089 03/17/07 06:25 PM
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Don't we all love home/barn owners that decide to remove braces because they seem to be in the way and there also seem to be just to many of them? The frame still holds up but dare you to remove the siding.

Todays siding cannot be compared with the cladding 100 years ago. It is only 1/2" thick at the most. Old siding was 1". So it could very well strenghten the frame even if braces were removed.

Re: Braces #4090 03/18/07 01:54 AM
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northern hewer Offline
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Well said everyone:

Timberframing as we call it really is Carpentry work using what was available to the builders in years gone by (timbers)

Building buildings using timbers has developed over many generations starting in numerous father lands and finding its way here to NA.

Remember we didn't invent building buildings with timbers, we only rediscovered it lately

nh

Re: Braces #4091 03/18/07 01:47 PM
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watching this fantastic discussion unfold has been extremely interesting. I laud you all for your wisdom and willingness to share it. Ron

Re: Braces #4092 03/19/07 12:02 AM
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When calculating shear caused by tension in a brace is the peg the only factor considered? A well made timber joint has more strength than just the breaking strenght of the relish behind the peg. A sloppy m&t would greatly reduce the joints strentgh and would fail at the weakist link, the peg if put under tension stress. The system probably still wouldn't fail the opposing brace would still provide substantial support in compression.


Timothy W Longmore
Re: Braces #4093 03/19/07 01:44 AM
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I have heard about unpegged bracing but I did not know it was widespread. I cannot recall seeing an unpegged brace in northern New England. I have seen a barn where the braces were not flush with the outside face but held in around one inch. Sheathing boards are often nailed to the braces. Brace tenons are often 3 1/2" long to 4", always barefaced. Long braces are extremely rare in my experience. Peg materials I have seen are usually red oak but I just surveyed a barn with hexagonal pitch pine pegs and an ell with octagonal red maple pegs, both here in Maine.

Does anyone know how the framers of yesteryear decided to size there braces? Why 36" vs 42" vs 48" etc.

Thanks; Jim


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"Heavy timber framing is not a lost art" Fred Hodgson, 1909
Re: Braces #4094 03/19/07 12:56 PM
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HouseWright
I agree. I know there are different regional framing styles, but un-pegged braces is not something that I’ve seen often in the NE. This could be likened to the scarf over brace or scarf over post issue?

Timbo,
I think you’ll find that the brace mortise and tenon joint failure mode is controlled by the tenon relish. I believe that the research by Dick Schmict’s and other’s support this conclusion. Ed Levin has also written a few articles on the engineering implications of allowing braces to carry tension, and conversely not allowing the braces to carry tension. The problem with allowing the brace tenon joint to fail mathematically in tension or to carry no tension load or do to actual loading, is that the only other load carrying mechanism that is available is post bending and/or girder bending. We’ve tried to mathematically release the tension capacity of the brace and have had trouble accommodating the addition loading on the frame. There are obviously issues with trying to accommodate high tension loads on your typical brace arrangement.

I would like to hear how other engineers who participate in this forum handle this problem. This has been one of the most difficult TF engineering problems for me. I try to design what I consider ‘well braced’ buildings. I use lots of braces and ‘deep’ braces were I can, but the brace tension issue will not go away.

I’m not sure if there is a benefit of starting another thread in the TF engineering forum to further discuss this or continue here?

Thanks, pete

Re: Braces #4095 03/19/07 04:49 PM
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beerfreak, It seems to me it would also depend upon lay-out method which would depend on the wood. It seems that if the square rule method was used and thus housings had to be cut because of different dimensioned timbers it would make more sense to have the shoulder run to an outside face. It takes a lot less time to cut a housing for a brace if you can cut from an edge as opposed to cutting a housing with wood on each side of it. I'm no expert on tradtional barns but it seems that with the tools available it would have been a certain mess to center a brace in square rule without a router, instead run the brace to a face, handsaw, then chisel.

Re: Braces #4096 03/19/07 11:53 PM
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--------------------------------------------------------------------------------
[Originally posted by beerfreak:
I have decided to fit the braces in the centre [center] of the post and peg all the way through as the car port will be open,so walls or cladding do not apply.
I am looking at 6"x 2.5" braces curved and 30"x 30" from the corner of the post if you can visulise it,the height up to the wall beam is 8ft,do you think this size of brace will look in scale.]
Wow. There is a wealth of info on here I am trying to digest it all. The sizes of green oak are 7"by 7" posts and beams.

Re: Braces #4097 03/20/07 02:57 AM
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It is pretty easy to scribe a brace into a plane other than flush with reference, but I've not seen it done historically on this side of the Atlantic.

I've seen but one SR'd barn with centered braces, but it doesn't count, it was commisioned by a wealthy industrialist who returned to his hometown and was atypical from top to bottom. They achieved it by plowing the housing all the way across the face and it is ugly as sin.

If this thread morphed into a discussion on regional variation that might be interesting. I likewise have never seen an unpegged brace here in NNE. Have long tried to research why common purlins are dominant here, and most of the scarfs I know of fall over nothing whatever, but between the braces and are most often bladed abutments or believe it or not, are free tenons, long abbuting bridle joins and a chunk of plank


"We build too many walls and not enough bridges" - Isaac Newton

http://bridgewright.wordpress.com/

Re: Braces #4098 03/20/07 03:27 AM
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The (really old builders ) did take racking into account. Some used knee braces on the top of ties in addition to the commonly used ones below.

Another issue is the lenght of the brace and how that effects racking. There is a documented example of a 400+ yr old stucture in eastern NY. The corner posts have braces that extend nearly 3/4(!) the height of the post they are supporting, would you expect such a frame to rack (or not pass code for such...)? These braces extend from the sills to nearly the top of the posts. It withstood 400 years of all those "northeasters" until it was dismantled for restoration ..... where will the "stronger" stick built buildings be in 2300?

To quote the reference" Each corner post had two great braces from the tops of the posts to the sills, used to keep the wind from wrenching the frame" " They intersected with half lap joints the two outside wall girts--smaller cross beams between wall posts used to nail on boarding. There were in addition to the regular braces at the intersection of cross beams with posts throughout the frame. Between them they appeared to brace a fortress against wind and tide." R. Babcock

Don't sell timber frames short, and do not limit your designs to what you have "seen" (or read) is the current fad or design. I'm sure ther are yet stronger TF buildings that can be achived!

P.S. Have seen many unpegged knee braces here in New England on buildings standing (still)

Re: Braces #4099 03/20/07 01:21 PM
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Bracing from post to sill has been a long or standard situation in Europe. And you'll see it here in New England also:



The reasoning behind this placement of down braces, sometimes called standing braces is that it transfers the wind load directly to the sill/foundation near the point of the load.
For standard "hanging braces" the wind load has to be transfered over to the opposing brace (that works in compression). Sometimes this opposing brace is several bays or aisles away. This means the entire frame is wrenched, wracked or shifted until the compression brace resists it.
A standing or down braces prevents this from happening by absorbing the load at the wall were it is being applied.
In a barn or outbuilding this whole frame racking won't matter that much, but a house with sheet rock could see some cracks or other evidence of the racking if it was pushed to extreme....

Jim Rogers


Whatever you do, have fun doing it!
Re: Braces #4100 03/20/07 01:47 PM
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Jim, A very nice example. Thanks!!!

On corner posts the racking effect can better be transmitted by truely long braces ( ca. 2/3-3/4 post height) otherwise the post holds the load above the brace. This is not always pactical in middle bents (except lenght wise along the sills) as the braces would extend into the structure's interior (O.K. if thats going to be an interior wall...) and complicates joinery by requiring a halflap at any bents inersected. Still it is a feature many ignore as a way to make a building more immune to racking.

Re: Braces #4101 03/20/07 09:33 PM
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Quote:
Originally posted by Mad Professor:
Jim, A very nice example. Thanks!!!

On corner posts the racking effect can better be transmitted by truely long braces ( ca. 2/3-3/4 post height) otherwise the post holds the load above the brace. This is not always pactical in middle bents (except lenght wise along the sills) as the braces would extend into the structure's interior (O.K. if thats going to be an interior wall...) and complicates joinery by requiring a halflap at any bents inersected. Still it is a feature many ignore as a way to make a building more immune to racking.

Re: Braces #4102 03/20/07 09:37 PM
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Quote:
Originally posted by Mad Professor:


On corner posts the racking effect can better be transmitted by truely long braces ( ca. 2/3-3/4 post height) otherwise the post holds the load above the brace. Still it is a feature many ignore as a way to make a building more immune to racking.
That's why the German design uses long braces going down instead of cute little braces between post and tie beams that do little.




Re: Braces #4103 03/23/07 12:49 AM
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HI all good thread and many good view points!!

Just food for thought:

On an open sided 10 bay drive shed such as would have been customary for church drive sheds from the earliest dates, how could you have used long braces on the open sides?

At the most only short braces could have been used, and that would have been from above the tie beams above the carriage openings to the upper plates. These outbuildings survived until they were made obsolete by the automobile. the ones used on all the farms are still around.

I also have seen long braces, but only in New World Dutch barns, and were inserted as sway braces. this framing style originated around the Pennsyvania area. The new England examples though, I always put it down to frames built originally by shipwrights, who being extremely precise in their work went that extra mile and used long braces wherever they could needed or not.

One thing I know for sure is that long bracing never really caught on at least in our neck of the woods, something like the Dutch Barns with the large anchor beams, the style quickly vanished the builders adapting to the 3 bay English barns style which predominantly used short braces of varying lengths and either square or rectangular in cross section.

NH

Re: Braces #4104 03/23/07 02:33 PM
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The reference I refered to was a 1574 "forest chapel" built by the French estabilished northeast of Troy NY (Hoosic). As "re- discovered" it was used as a barn but it's construction gave away its original purpose. The beams were marked (scribed) with the original divider settings which included arrows instead of roman numerals used to delineate the various bents. The braces gave away that it was not just a barn, but Gods house, and meant to last!!!

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