Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
five sided ridge beams #12807 09/10/07 05:18 PM
A
Anonymous
Unregistered
Anonymous
Unregistered
A
HI Everyone;

Does anyone know the origin of the five sided ridge beam? I have seen several here in Mid-Coast Maine, both in rafter-purlin and common rafter roof systems. I know they are common in the Connecticut River Valley.

Are they always hewn? When did they go out of style?

Thanks;
Jim

Re: five sided ridge beams [Re: Anonymous] #12812 09/11/07 11:15 PM
Joined: Nov 2006
Posts: 850
mo Offline
Member
Offline
Member
Joined: Nov 2006
Posts: 850
Well what is it? Is it a ridge where the rafters connect perpindicular to their pitch? Does it look like a pentagon where it is pulled at the midsection down? I definitely don't know the origin but I am interested in it nevertheless.

Last edited by mo; 09/11/07 11:17 PM. Reason: pentagon for hexagon,
Re: five sided ridge beams [Re: mo] #12814 09/12/07 01:09 AM
Joined: Nov 2006
Posts: 850
mo Offline
Member
Offline
Member
Joined: Nov 2006
Posts: 850
Wait a minute all ridges have five sides.

Re: five sided ridge beams [Re: mo] #12817 09/12/07 01:28 AM
A
Anonymous
Unregistered
Anonymous
Unregistered
A
Hi MO;

I am sure I need to provide a drawing or photo to fully explain a five sided ridge, but I do not have time to post one right now.

I am talking about frames which have a ridge beam, not a ridge board, into which the tops of the rafters are tenoned and pegged. The essential timber framer's joinery reference book Historic American Timber Joinery gives a discription on page 38.

There certainly are an amazing number of variations of how historic timber frames were built!

Jim

Re: five sided ridge beams [Re: Anonymous] #12822 09/12/07 12:50 PM
Joined: Mar 2002
Posts: 1,685
J
Jim Rogers Online Confused
Member
Online Confused
Member
J
Joined: Mar 2002
Posts: 1,685
Not all ridge beams have five sides, a four sided beam will work, two roof planes and two rafter joint faces....
I've cut five sided ridge beams on my sawmill before...


Whatever you do, have fun doing it!
Re: five sided ridge beams [Re: Anonymous] #12823 09/12/07 02:36 PM
Joined: Apr 2006
Posts: 125
Joe Bartok Offline
Member
Offline
Member
Joined: Apr 2006
Posts: 125
Originally Posted By: "mo"
Well what is it? Is it a ridge where the rafters connect perpindicular to their pitch? Does it look like a pentagon where it is pulled at the midsection down? I definitely don't know the origin but I am interested in it nevertheless.


We have cut pentagonal ridge beams where one plane followed level, two planes were plumb and the remaining two planes followed the slope of the roof. Unfortunately I don't have a decent picture with detail that I can post.

And I have seen drawings where two faces of the beam were perpendicular to the rafter slopes rather than plumb. To my thinking this would be preferred ... cut square whenever possible.

Re: five sided ridge beams [Re: Anonymous] #12829 09/12/07 11:09 PM
A
Anonymous
Unregistered
Anonymous
Unregistered
A
Hi

Here are a picture of a four sided (diamond) ridge beam in a house in Warren, Maine and a five sided ridge beam in a barn in the neighboring town of Waldoboro. Both buildings were built in the 1790s.





Notice how the diamond ridge ends but the building keeps going. This is an unusual roof system in an L shaped house. The only reason I can imagine to mix the roof framing was to handle the hip and valley framing with the ridge beam and frame the rest the easier way, with rafters which meet at the top with a lap joint.

The ridge beam in the barn has some wind braces between the ridge and rafters.

I have only seen about six or seven old frames with ridge beams and they have always been hewn.

I think frames with ridge beams are more difficult to raise (and disassemble) which is why I want to know more about them...Anything harder than it had to be had a reason.

Jim

Re: five sided ridge beams [Re: Jim Rogers] #12842 09/14/07 12:12 AM
A
Anonymous
Unregistered
Anonymous
Unregistered
A
Hi

Here are two photos of ridge beams. The first is a diamond shaped, four sided ridge in a house in Warren, Maine. The tops of the rafters are cut at an angle to match the ridge and the tenons angle upward slightly to be perpindicular to the edge of the ridge.

Note the ridge beam stops but the building keeps going. This is an unusual example of mixed styles of roof framing within the same frame. There are three common rafters which join with a pegged half lap at the peak. I think they used the ridge beam in the middle of this L shaped house to handle the hip and valley framing.



The second photo is a barn in the neighboring town of Waldoboro. There were twin 30 x 30 barns and the house were all framed with five sided ridges and common rafters. Note the wind bracing from the ridge to the rafters. I think this is the only advantage of having a ridge beam... to have bracing in the roof.

All of these buildings date from the 1790s.



I have seen rafter/purlin roof systems with five sided ridge beams too.

Jim

Re: five sided ridge beams [Re: Anonymous] #12872 09/18/07 12:21 AM
Joined: Nov 2006
Posts: 850
mo Offline
Member
Offline
Member
Joined: Nov 2006
Posts: 850
Maybe the five sided ridge was this way so there was not a compound angle to find between the brace and ridge. If the sides of the ridge were plumb then that the angle of wind brace to ridge would be a little bit trickier to find. Also, it seems that if the pitch is anything but 12:12 the five sided would have to be used in place of the four sided. Thanks for the pictures.

mo

Re: five sided ridge beams [Re: mo] #12875 09/19/07 01:20 AM
Joined: Nov 2006
Posts: 850
mo Offline
Member
Offline
Member
Joined: Nov 2006
Posts: 850
By the way, how the hell did they raise this frame? The one with the five sided ridge.

Page 1 of 2 1 2

Moderated by  Jim Rogers, mdfinc 

Newest Members
HFT, Wrongthinker, kaymaxi, RLTJohn, fendrishi
5134 Registered Users
Powered by UBB.threads™ PHP Forum Software 7.7.3
(Release build 20190728)
PHP: 5.4.45 Page Time: 0.033s Queries: 16 (0.009s) Memory: 3.2095 MB (Peak: 3.3984 MB) Data Comp: Off Server Time: 2024-03-28 11:11:26 UTC
Valid HTML 5 and Valid CSS