Structural Ridge Beam: A Real World Example
HTML-код
- Опубликовано: 11 сен 2024
- An explanation and real world example of a structural ridge beam used to support roof rafters. See how a structural ridge was used to tie together a 1700s timber framed roof with a modern roof framed with 2x rafters. Learn the difference between a ridge board and a ridge beam.
I have been watching different videos to understand the difference between the ridge beam and the ridge board. You explained it very clearly. Thank you very much!
It's really nice watching videos made by a contractor that knows what the hell they're doing. It doesn't take much more cost to do things the correct way, never having to worry about it coming down on your head. Nice work tying the new to the old structure.
Collar ties do not prevent rafters from splaying out where they attach to the walls. They prevent the rafters from separating at the ridge during uplift. Rafter ties or floor joists are what prevent the walls from spreading from roof loads (down force).
Thank you so much,the structural ridge is so well explained ,that it all makes perfect sense on the roof construction for the dormer !
Thanks for defining the terms you use. That really helps.
finally someone explaining in simple terms
Good heavens same here; people just walk a camera around a construction site and ask you to 'smash the like button' - I want to say 'you taught me nothing!'
This guy presents the information like an actual instructor would! Very grateful!
Thanks, nice description and helped me understand the difference....good seeing both the drawings and the actual beam in place :)
Very very clever. That's about as difficult/tricky as it gets, nicely done. Thank you for the video and explanation of things.
Hey what book is that you're looking at at the beginning?
Great video. I learned a lot. Thank you.
What are you showing images from in the beginning? Is that a book of details, or project specific?
See this video: ruclips.net/video/HGtJaaLguR4/видео.html and there is a link in that comment section to purchase the book if you like.
just what i was looking for
Nice video. I'm not sure I understood your explanation for the collar ties in the beginning of your video. I think you said the collar ties keep the rafters from spreading apart at the bottom. When I took building process in college, it was always understood that the ceiling joist kept the rafters from spreading apart at the bottom and the purpose of the collar ties were to keep the top of the rafters tight to the ridge during high wind. Nice work tying in new construction to 100 year old existing.
Ruben Rojas The building in this video is a weird mixture of framing styles, but in more typical circumstances you are right. In a gable framed structure the floor/ceiling joists form the bottom chord of the triangle that keeps the walls from spreading under the weight of the rafters. However, when you have a structural beam designed at the peak of the triangle the beam carries the load and prevents the rafters from pushing out the walls. Collar ties (strictly speaking) are framing members installed in the upper third of the rafter triangle and are meant only to keep the rafters from spreading apart at the top during unbalanced loads on the roof (like snow or wind). The term is often confused with rafter ties, which are those floor/ceiling joists or similar arrangement at the bottom of the triangle. In fact, I have had municipal building inspectors insist on collar ties in the upper third when in fact they were confusing the two principals at work here. What can I tell you--there are lots of these sorts of confused traditions in construction!
Thank you for clearing that up for me. I 100% agree with you. I too have experienced many contractors confuse one for the other or both framing members to serve the same purpose. The confusion is so common, that being a framing contractor, people tend to doubt my product when I disagree with anyone who believes collar ties keep rafters from spreading at the bottom.
Ruben Rojas
I admit to occasionally using the wrong term on purpose for this and other construction techniques only because it's the only way I can communicate with others! Construction is full of these points of confusion, as well as regional differences in technique that further complicates matters. In theory the national and international building codes should cut down on the confusion but in practice they are so poorly implemented and policed that they only make matters worse. And, the vast majority of contractors and workers learn on the job from others, so the confusion just gets passed down the generations.
I noticed in your video that the ridge beam sits on support posts that appear to be over openings. Did you beef up the headers over those openings and add support posts to carry the load down around those openings? I heard you say that the load is carried by the existing walls.
***** In this particular case there was a masonry wall on one side of the beam and a post and beam wall on the other side, so the existing structure was plenty to carry the load. That isn't always the case, however.
THAT WAS GOOD INSTRUCTION!... I HOPE YOU DO MORE VIDEOS....I SUBSCRIBED!... THANKYOU BUD!
What book are you using for reference in the video?
Building Construction Illustrated. Great book--see my review here: ruclips.net/video/HGtJaaLguR4/видео.html
Nice explanation of the ridge board and ridge beam. I noticed you hung the original timber frame rafters off the ridge beam. What hanger did you use for that? Thanks again!
I'm trying to remember! There is no metal hanger for the timbers, since they are all different and random widths. I believe I may have used timber screws which were screwed in from the opposite side. I installed the ridge beam in three pieces since it was heavy and difficult to get up there. I probably used whatever structural or timber screws which were available at that time and screwed into the end grain of the timber rafters. Perhaps I toe-nailed as well. The timber rafters were likely oak, so they could easily take the big screws without splitting. The roof sheathing and shingles stayed in place, so through-bolting was not an option. Today there is a wide variety of structural screws and lags available for any conceivable circumstance, so the selection would be easier. I've continued to do work for the couple who own this old house, so I know the beam has held up!
Why are the ceiling joists so wide? Are they not just for attaching a (light plasterboard type) ceiling?
The ceiling joists are only 2x6, which is the minimum you'd want for the span in this case. The video may make them look bigger than they are.
Thank you sir!
So a house with a sagging ridge board might not have an issue as long as the rafters are still in a good position?
If you have a sagging ridge there could be multiple reasons. A sagging ridge when constructed from a ridge beam means that the beam is undersized or damaged and needs some attention right quick! If you simply have a ridge board and rafters (meaning the ridge board itself is not structural) and it is sagging, then it may be that the middle rafters have sagged too. This can be caused by a poor connection at the rafter/top plate intersection so that the rafters have slid out, or it can be caused by an inadequate connection or design of the ceiling joists that make up the bottom chord of the triangle. In the latter case, the walls themselves my be bowed out as the rafters have smooched downward and pushed the walls out with them. If you have a truss roof and it is sagging, it's most likely damaged structure. In any case, a sagging ridge can often be sign of trouble, so don't ignore it.
good job, look like it could withstand category 8 hurricane , whats is the estimate on 1 shed dormer w/material ?
+Dharma Kissoon There are too many variables to give generic advice on cost, but any time you are opening up a roof and making structural changes you should expect a significant outlay. An architect or engineer is likely to be needed in most states for building permits to be approved and typically a carpenter or remodeler can give you an estimate based on those drawings.
@3:30 those rafter joists, that's hurricane ties to hold the roof down, not support rafter joists.
You're confusing two things. The hurricane ties, which are normally used to tie the top plate to the rafter ends, were used here to reinforce the CEILING joists. Those ceiling joists on that end were also toe-nailed in several spots. The unusual use of hurricane ties in this instance was due to the unusual framing situation which married 18th century timber framing on one side and the modern framing on the other. To be clear, those ceiling joists only carried the weight of the drywall and nothing else. The rafters, by contrast, were hung from the ridge beam using framing connectors in the standard way. The use of hurricane ties for the ceiling joists was specified by the architect and approved by the local building inspector. I've been back to this house many times for other work, and there are no cracks in the ceiling drywall many years later.
Hello great video, I have a question. My Dining room/Kitchen combined is 24 x 20 with a 2x4 trust system with 2x6 rafters and a 1x6 non structural ridge that is 5' from the top of the ridge to the bottom of the trust. My Contractor wants to sister up the existing rafters with 2x10s with hurricane ties at the top plate of the wall and install 2x10 collar ties at 1/3 down (20"mark). My question is this strong enough to support the existing roof that is made up of 1/2"plywood and 1 layer of shingles as opposed to adding a new ridge beam posted down to the carrying beam in the basement on either end and then doing everything as above. I live in New England where we do get snow. Also I am doing this to raise my ceiling height from the existing 8' and would be happy with 9'
Also 1 thing I forgot to mention is the rafters are 24" On Center
Oh boy. Lots going on in your question! It's tough to communicate technical details over the interweb sometimes, and I'm not at all certain I have a mental picture of your roof framing. So, I'm forced to speak in generalities here. Truss systems, if that's what you really have, are engineered framing members typically made from 2x4 material or man-made lumber material and often connected together with special plates. Trusses are designed and made in a factory and then hoisted into place at the job site. Since trusses are highly engineered systems meant to handle loads in specific ways, you cannot (and should not) modify them without the direction of a structural engineer. So, if you really have a truss system, your contractor needs to have a structural engineer (or architect) sign off on a plan, and your building inspector will also require this. You mention sistering up conventional 2x10 rafters to these trusses, which is definitely not a typical or common thing to do.
Having said all that, it is possible you don't actually have engineered trusses and that your contractor was using the term loosely or that I haven't fully understood your description. Still, when making significant changes to framing like this, a building permit is required in your state (and probably all states) and that permit will likely require an architect or engineer to sign off on the details. I know people often don't want to be bothered with permits, but this is one case where the building code really is protection your interests. You correctly note the concern about snow loads in New England, which can get very heavy. I would sit down with your contractor and make certain you understand his plan and that he understands you expect him to pull a building permit. That way somebody will be checking over his work and you can rest easy.
I apologize if it's rude to jump into another person's question to ask my question, but I saw that trusses were mentioned here. We would like to convert our gable style roof to a monopitch/shed roof, so we are in the researching process and we're curious about whether we should use rafters or trusses?? The gable/side of house is about 45 ft long and the front of the house is about 25 ft. (The high point at front of house and low point at back) I came to this video because we're curious about the need to extend walls, add structural beams etc..
I'm not certain I have a mental picture of your intent. Regardless, you'll obviously need an architect to design whatever it is you intend to do. S/he will be able to make a judgement call about conventional framing versus trusses. It may well be a matter of cost or ease of installation. There is no functional difference between conventional rafter roofs and those with trusses--if they are properly designed for the load either will hold up the roof. However, trusses cannot be altered easily after the fact and they may limit use of the interior attic space depending on the type of truss design. One or the other system may be advantageous for your particular existing wall framing. But, it will take an experienced architect or engineer on site to make that call.
Thank you! I was thinking trusses are only used on new builds with no ceiling joists. I thought the lower part of the truss serves as a ceiling joist.
great video!!!
thanks very useful to me
What book are you referencing??
Great book, and I reviewed it in this video at 1:54
ruclips.net/video/HGtJaaLguR4/видео.html
So how long can you make a structural ridge beam without having to put a support under it. Just curios. Thx for the info.
That depends entirely on the strength of the beam. In residential construction you can go about as long as you'd ever need to, especially when you get into engineered beams or steel beams. The limiting factor can be the height of the beam, which can start to look silly if you attempt very long spans. 30 and 40 foot spans are routine.
Are those hurricane ties holding up the ceiling joists on the interior end? ;-)
The ceiling joists (which were only holding up drywall) are actually toenailed into a 2x member spanning the opposite side rafters, but the hurricane ties were used to add strength out of an abundance of caution. The whole thing was a bit of a bizzare mix of old and new, but I've driven by the jobsite and it is still standing, so I guess it worked!
where can I buy that book?
I have a whole video review for you! Link to purchase is in the comment section:
ruclips.net/video/HGtJaaLguR4/видео.html
@@enduringcharm nice!! thank you
Great video. What book was it that you used for your description?
That's from an old book I have called Building Construction Illustrated by Francis Ching. Don't know if it's still in print, but it's a whole book of drawings like what you see in the video--very useful to help people visualize construction.
The book "Building Construction Illustrated" by Francis D. K. Ching, is still in print at Barnes and Noble or on Amazon for around 35 buck new or alot less used.
John Painter you have Great video! Shouldn't you have been a painter!?
Hot Rod
There was a mixup at the hospital with the Carpenter family. I've learned to accept it.
What is that book your using? I like it.
That awesome book is Building Construction Illustrated by Francis DK Ching. Highly recommended to help visualize various aspects of projects--I've used it many times to help clients understand what is going on.
What is the span?
It's been too long for me to remember, but those were 16 inch centers so if you can find a section of video to count the rafters you can get an approximation.
WOW did I just get an education here.
Dude thank you ..I'm young guy and I know my engineer out to lunch this video going as far up his ass as I can put it ... Thanks for the knowledge ... Keep ur head down ass up .. build the world ... .. thanks
It seems like a sin to put an addition on like that to a beautiful old timber frame. Nice example of a Ridge beam though. Nice.
You should have seen what we took out! There was a badly designed and framed double dormer installed in the 80s that we took out, which was a train wreck. This shed dormer was a much better design, proportioned to the house and in keeping with the style. We finished off the inside with some recycled timber beams made to look structural.
A one pitch is never a good design.
Oh, you mean the roof angle? This installation had a standing seam metal roof installed rated for low pitch. It hasn't been a problem yet.
enduringcharm that's a good roof system, those flat pitches are always a trouble area.
Agreed--flat roofs are typically trouble sooner or later. This one was coated entirely with Ice & Water shield and then a custom standing seam was fabricated. It's the rubber roofing and the hot tar roofing where I see the most problems.
Steve Buscemi?