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Jeff Root
2005-Dec-10, 03:49 AM
Can anyone tell me what the architectural term is for the
supports of the overhanging roof in this drawing?

http://www.freemars.org/jeff/misc/supports.png

Thank you!

-- Jeff, in Minneapolis

teri tait
2005-Dec-10, 04:08 AM
Joice?

ToSeek
2005-Dec-10, 04:15 AM
I was thinking "joist", too, but that seems to refer to part of a frame.

sarongsong
2005-Dec-10, 05:04 AM
Looks like something no architect would have designed; got any actual examples/pics?

Philip A
2005-Dec-10, 05:09 AM
Not an architect, but looks a bit like a flying buttress.

HenrikOlsen
2005-Dec-10, 05:13 AM
I'm thinking "brace".

Candy
2005-Dec-10, 05:28 AM
Joist (http://www.hancockjoist.com/glossary.htm) has many references according to this glossary.


Joist
A structural load-carrying member with an open web system which supports floors and roofs utilizing hot-rolled or cold-formed steel and is designed as a simple span member.

Joist Designation
A standard way of communicating the joist safe uniformly distributed load-carrying capacities for a given span such as 16K5 or 24K10 where the first number is the nominal joist depth at midspan and the last number is the chord size. See Longspan Designation and Joist Girder Designation.

Joist Girder
A primary structural load-carrying member with an open web system designed as a simple span supporting equally spaced concentrated loads of a floor or roof system acting at the panel points of the joist girder and utilizing hot-rolled or cold-formed steel.

Joist Girder Designation
A standard way of communicating the girder design loads such as 48G6N10.5K where the first number is the nominal girder depth at midspan, 6N is the number of joist spaces on the span of girder, and 10.5K is the kip load on each panel point of the girder. The approximate dead load weight of the member is included in the kip load. See Joist Designation and Longspan Designation.

Joist Manufacturer
The producer of joists or joist girders who is SJI approved.

Joist Spacing
The distance from one joist to another.

Joist Substitute
A structural member which is intended for use at very short spans (10 feet or less) where open web steel joists are impractical. They are usually used for short spans in skewed bays, over corridors, or for outriggers. It can be made up of two or four angles to form channel sections or box sections. See Angle Unit.

paulie jay
2005-Dec-10, 05:38 AM
Not an architect, but looks a bit like a flying buttress.
Well, I think your buttress is all about bearing load is it not?

LurchGS
2005-Dec-10, 05:41 AM
definately not a flying buttress...

I'm gray on 'joist' - I commonly think of a joist as a *horizontal* structural member. Off the cuff, I'd agree with Henrik and call it a brace, as it's halfway between a joist and a post

Candy
2005-Dec-10, 05:47 AM
Same glossary - Braced Frame (http://www.hancockjoist.com/glossary.htm)


Braced Frame
A frame which resists lateral loads by the use of diagonal bracing, K-braces, or other system of bracing.

Enzp
2005-Dec-10, 05:49 AM
I think a flying buttress would be leaning into the wall rather than out from it. Plus the butress' job is to hold the wall upright so it doesn't collapse under the weight of the roof.

"Roof overhang support" comes to mind.

Candy
2005-Dec-10, 05:51 AM
Hey, look what I found! :)


Overhang
The extension of the top chord of a joist beyond the outside of the bearing support. See Top Chord Extension.

Top Chord
The top member of a joist or joist girder.

Top Chord Bearing
The bearing condition of a joist or joist girder that bears on its top chord seat.

Top Chord Extension (TCX)
The extended part of a joist top chord only. This type has only the two top chord angles extended past the joist seat. See Overhang.

Philip A
2005-Dec-10, 05:51 AM
Well, I think your buttress is all about bearing load is it not?

Granted it's sort of inverted, but it does bear the load of the roof!

Melusine
2005-Dec-10, 05:55 AM
I'm thinking "brace".
That's what I was thinking...roof braces. I did a Google image search on "roof braces" and that's what sites called them. I can't find a more specific term in architectural glossaries.

An example:
http://community.netidea.com/powder/const19tn.jpg

Melusine
2005-Dec-10, 06:01 AM
Granted it's sort of inverted, but it does bear the load of the roof!
Think of cathedrals--the buttresses go from inside to outside to support the walls from the lateral movement of the roof.

Look here at flying buttresses
http://images.google.com/images?svnum=10&hl=en&lr=&q=buttress

Philip A
2005-Dec-10, 06:22 AM
Think of cathedrals--the buttresses go from inside to outside to support the walls from the lateral movement of the roof.

Look here at flying buttresses
http://images.google.com/images?svnum=10&hl=en&lr=&q=buttress

Yep. Agreed, it's not a flying buttress.

Jeff Root
2005-Dec-10, 07:56 PM
Fifteen replies in less than 2-1/2 hours! Then no more!

Thanks for your attempts. Joists are the structural members
which floorboards or roof boards (I don't know the right term
for roof boards either) are directly nailed to. Joists are
usually supported by horizontal beams. Joists under a floor
are of course horizontal, but those under a roof are at the
angle of the roof. The two structural members in the drawing
support the roof joists, which I didn't try to show. If I
can't find a better term, I'll call them "beams".


Looks like something no architect would have designed
I wonder if the lack of details combined with the imperfect
perspective made the geometry of the picture confusing, like
an Escher illusion. Otherwise, why do you say it looks like
something no architect would have designed?

Candy, thanks for your search efforts. It looks like the
glossary you found is geared more toward steel and concrete
bridges than wood-frame houses. My drawing was intended to
depict the front entry of the house I grew up in.

Melusine, the term "brace" is too general, with too many other
meanings to be clear in this context. How did you find that
example photo? Did you just happen to know it was there?

-- Jeff, in Minneapolis

Candy
2005-Dec-10, 08:11 PM
If I
can't find a better term, I'll call them "beams".
I prefer the term, stud. ;)

Your image reminded me of a camp like structure. Thanks for bringing back memories.

Jeff Root
2005-Dec-10, 08:40 PM
Oops! Correction: The supports for the roof boards are called
"rafters", of course. Apparently rafters are to roofs as joists
are to floors.

-- Jeff, in Minneapolis

Jeff Root
2005-Dec-10, 08:58 PM
I prefer the term, stud.
I suppose you'd like to see the Captain's log?

Actually, I need the term for a story. The protagonist leaves
all her belongings in her school locker, where she won't be able
to get at them over the weekend. I realized that would mean
she doesn't have her house key, and so can't get into her house
unless someone else is home, which she can't count on, so I
decided that she has a spare key hidden on top of one of those
beams-- just like I had at my house.

The term "beam" is used later in the story to describe a large,
horizontal timber, so I wanted to avoid using it elsewhere in
the story if I could avoid it.

The term "stud" is used in the story several times, too,
although it isn't made of wood... I didn't say what kind of
story this is, did I? No? That's good!


Your image reminded me of a camp like structure.
I see that, too, now that you point it out.

-- Jeff, in Minneapolis

Wolverine
2005-Dec-10, 09:01 PM
The double entendre is not appreciated. Family-friendly board.

Melusine
2005-Dec-10, 10:07 PM
Melusine, the term "brace" is too general, with too many other
meanings to be clear in this context. How did you find that
example photo? Did you just happen to know it was there?

-- Jeff, in Minneapolis
Yeah, "brace" is general, but I couldn't find anything else that fit that sort of thing in the architectural glossaries, so I did a Google image search on "roof braces" and "braces for roofs." Seemed better than "roof supports" which people call them, as well. Good luck.

http://images.google.com/images?svnum=10&hl=en&lr=&q=braces+roof

The (http://www.woodmags.com/wdb/magazine_rack/1998_summer_4/fishtrap_creek/pics/photo3.jpg) site for this picture calls these "support columns with radiating braces made of salvaged timber."

There's a site in the UK that calls them "eaves braces."

Joff
2005-Dec-10, 10:11 PM
I'm voting for "eave brace" or "eaves brace". The diagonal nature of this support member definitely supports that name ;) and the overhang is the eave.

If it's in a story, and with this much confusion among reasonably erudite people, you'll probably need to describe it anyway.


The double entendre is not appreciated. Family-friendly board.Ah, get over it Wolverine. Either someone knows what they're talking about, or the reference goes straight over their head.

SolusLupus
2005-Dec-10, 10:21 PM
Ah, get over it Wolverine. Either someone knows what they're talking about, or the reference goes straight over their head.
"Get over it"? That doesn't seem like a very wise thing to say to a moderator.

paulie jay
2005-Dec-11, 12:35 AM
Granted it's sort of inverted, but it does bear the load of the roof!
Right you are - I was meaning to answer more in the way that Enzp did

"...I think a flying buttress would be leaning into the wall rather than out from it. Plus the butress' job is to hold the wall upright so it doesn't collapse under the weight of the roof..."

But it never really came out!

mugaliens
2005-Dec-11, 08:02 AM
Studs are the vertical members in walls, usually 2x4s in the states.

Headers and footers go on top of, and below the studs.

The rafter sits inside the roof, and is the triangular structure used to support the roofing panels over which tarpaper is laid and to which shingles are nailed.

Beams are indeed horizontal, usually under tension to prevent walls from spreading due to roof loads, but are also used to center-support floor joists.

Braces are usually angled, and are used as temporary structures to hold up all manner of construction until the construction is more complete and self-standing.

Joists are indeed used in flooring.

A buttrece is an external structure used to prevent walls from spreading.


The piece in the picture is holding up the eave, which is an extension of the roof. They're not pictured, but it would rest against the rafter. Because it's lower than the cieling, and supported by the side wall, it's not a rafter.

When combined with the rafter and the side wall, the members meet the definition of a truss.

Technically speaking, the individual piece could be called an "angled rafter return."

LurchGS
2005-Dec-11, 08:08 AM
THAT's the word I was looking for!

Truss

Candy
2005-Dec-11, 08:10 AM
I think "we" scared Jeff Root away from the thread. I'm sorry, but... :lol:

mugaliens
2005-Dec-11, 04:05 PM
Ahhh... Sorry. Too much info?

Candy
2005-Dec-11, 07:22 PM
Ahhh... Sorry. Too much info?
I meant for a different reason. ;)

One can never get too much information in my "book".

Wolverine
2005-Dec-11, 08:33 PM
Ah, get over it Wolverine. Either someone knows what they're talking about, or the reference goes straight over their head..

Off-color comments are not welcome here, and I've received complaints about them in the past. It's my obligation to ensure everyone here follows the forum rules. Those same rules note:

If a moderator gives you advice, we advise you to take it.

Edited to add: I apologize for being so curt, and have removed the first part of my earlier statement.