What Is A Roof Purlin? - House Framing And Construction

www.homebuildin... Click on this link if you're interested in learning more about roof framing, building design and home repairs. This video will provide you with a simplified explanation of what a roof purlin system for house framing does and how it can be used to distribute the load of a large roof or roof rafters more effectively. This system would also allow for smaller size lumbered to be used and seems to be rarely used today, but was often used in homes built before the 1960s. Remember, any modifications to the original structure of a building might require a structural engineer and building permits.

[@EngineerPEretired]

I would like to add, for your approval, purlins, " ...shal be installed to bearing walls at a slope not less than 45 degrees..." Plus spacing to to not be greater than 4 feet and the brace length shall not exceed 8 feet in length.

[@DanielaRouge]

Happy to find you! If you are kind enough and have the necessary time to answer to some questions I asked a lot of people, nobody gave me a right answer for. Here are my questions: I have a very big house and I want to cut it into 2 smaller houses, it's a long house. The cut is in a hall that has no attic, but has pillars supporting the roof. I want to cut the roof between 2 vertical posts/pillars, the posts running horizontally will be cut, one in the middle of the hall, the highest point of the roof, 2 others lower. Will the structure of the roof be damaged? The hall separates the 2 houses, then I want to demolish the wall on a distance of about 3,5m, the distance I want to take the roof off .The walls are in brick, very thick, 60 cm. Shall I put concrete pillars at the end of the walls, after demolishing? Then in one of the houses there are pillars coming from the attic into the rooms. Can I cut some of the , put them on beams in the attic and take them off from the rooms without damaging the structure of the roof? Thank you for all your videos, very informative and effective, I learned so many things from them.

[@gregvancom]

I have to admit, you are the first person I've ever heard of who wanted to cut a home in half. Obviously you have your reasons why, but I don't think I would do it, just throwing that out there. Feel free to send me some pictures of your attic and roof and I will see if I can help you out. You can get her email address at the website.

[@brainwashingdetergent4322]

Real funny thing… I had a friend of the family, a retired tradesman, a framer long enough to be competent, come and look at my restaurant. Long story short, the old walk-in refrigerator was once outside, but at some point, the kitchen was expanded and walls and a roof were built around it, now the walk-in is inside. I want to remove it, and the old timer took a look, and said he’d put kickers in to support the roof. What he calls kickers, you call purlins, and KZbin decided to put into my feed, a video about purlins, the same day he took a look at it… Edit, I commented too soon. What you call a brace, he calls a kicker.

[@capeverdeanmedia]

If I add another 2x4 lumber on each side across the middle of the 3 support bars, would it make the whole thing stronger?

[@lakewalker]

What is the process of installing the purlin braces? Do you nail off just one side of the diagonal brace, then proceed to lever the purlin into position while having a helper nail the other end of the brace to lock it into place?

[@justinsmith-cn9jo]

Nice Presentation

[@gregvancom]

Glad you liked it

[@MoneyManHolmes]

This type of support seems like it would put a diagonal load on the wall below instead of a straight down load. Especially if both sides aren’t fastened to the same wall to help balance each other out.

[@gregvancom]

I agree sometime it will be better to reduce the angle or use vertical supports.

[@coachgius]

Greg, my SE says to support rafters with acrow props all the way through from floor joists to the purlin directly. Though the purlin has not a flat surface being it at an angle. Any videos on ways to prop structures?

[@studyguides7670]

Thanks for sharing!

[@gregvancom]

You're welcome and thanks for watching.

[@timjeffries1555]

Rafter ties would be a good top off.

[@edbouhl3100]

If this was an old house in Southern California would it make the house more resilient to add metal hardware at the various purlin connections? If so, any specific hardware and locations, or just link everything together with hurricane ties?

[@gregvancom]

If you're looking for a little more strength and you don't mind spending a few more dollars, then go for it. However, I don't have any individual product recommendations.

[@edbouhl3100]

@@gregvancom Thanks for the quick reply! I’ll spend some quality time with the Simpson Wood Connectors catalog.

[@WaylonEMay]

I have that exact framing layout and steep roof with purlins, I did not find the video link about removing them.

[@gregvancom]

It might be here or in roof framing remodeling at our website. www.homebuildingandrepairs.com/attics/index.html

[@Chris-sl8fe]

Thanks for the great content! I am trying to install a whole house fan but purlin bracing is in the way. The purlin bracing obstructing my install is not tied into a load bearing wall. Rather, it is resting on a block sitting on the home's old flat roof (a pitched roof was built over the original tar/gravel flat roof). My tentative plan is to remove the purlin bracing pair and then add a rafter tie and also sister additional lumber to the purlin strong backs that span this particular area. Any initial thoughts or ideas are much appreciated.

[@gregvancom]

I cannot provide you with structural engineering advice for your individual project, because it could be confusing to others, but can tell you that I've seen what you're suggesting been done before. I think the best information I could give you would be to take a common sense approach to this problem. For example, if there's a way you can relocate the brace or modify it in a way to where it will still be supporting the structural load from the roof, then go for it.

[@deevidebyzer0]

Hi, I'd love to see your video on how to remove these purlins, beef up the floor to utilize the attic, but i couldnt see the link at the end of the video

[@gregvancom]

It's on my list and since there is not much of a demand for this remodel, I don't know when it will be made.

[@clemsmith2253]

I'm having trouble understanding IBC. It believe it says the rafter distance of rafter can be considered from ridge board to purlin. I am trying to reduce lumber depth of rafters for a long span

[@gregvancom]

Give me the page and reference number if you can from International building code book and I will take a look at it. Keep in mind I'm not an engineer.

[@MrMac5150]

Good Work.

[@gregvancom]

+MrMac5150 Thanks again for watching.

[@Bimmermeister]

How to calculate hip roof purlin loads? Dead and live loads over tributary area for each purlin are probably too great since the load bearing of the rafters minimizes the load. Intention is to remove load bearing stud wall and replace with wood beam with jack and king studs with load transfer to foundation below. Need purlin loads to design beam.

[@gregvancom]

I'm not an engineer, so won't be any help there.

[@ejrobinson2853]

My house's framing is exactly like in your video. I'm wanting to remove the load bearing wall in the center. Do you have a video or pictures of how to tie the ceiling trusses and purlin braces into a recessed beam. Thank you.

[@gregvancom]

I don't think so but you can go to the website for more video. Email me a picture or plans and I will take a look at what you're doing.

[@Flipping_Assets]

If you were to "lift" this roof up with a cran could you do it with this design and at which points should it be lifted from?

[@gregvancom]

That is definitely not my area of expertise and would suggest contacting someone with more experience on the subject. I'm sure it can be done, but don't know how much work would be involved or what the process would be.

[@kevinj.kinyanjui4192]

Great presentation! I have this exact type of roof and I'm planning to open up a 10 foot section of the load bearing wall below. I plan on having temporary braces for the purlins sit on the joists directly above my temporary support wall while I install a 2- 2x12 "beam". There is concrete footing on either end of where the beam will be. What other considerations do you think I should make? Thanks!

[@gregvancom]

I can't provide the engineering information you're requesting. However, I've seen 10 foot 4 x 12's support areas like that.

[@coachgius]

Say you want to expose the roof and eliminate the ceiling, can the purlins be eliminated and a reinforcement added at rafters level support them?

[@gregvancom]

You might need to check with an engineer on that one, but I have seen larger rafters installed so that roof purlins could be removed.

[@theblackduckaus]

If i have a roof with ceiling width approx 15m being held by 2 lots of purlins per side braced on internal walls can i remove the top purlins and use collar ties? The roof pitch is no more than 30 degrees I'm needing unrestricted access to those internal walls to replace ceiling joists with floor joist system for second storey before i remove the roof

[@gregvancom]

If you think you can do it safely, then go for it.

[@josebecerra8853]

Thank you for sharing the video what would you use if you want to move the bearing wall how would you support the purlings

[@gregvancom]

You could support it with a structural beam or another wall nearby.

[@lauraducker3005]

Jose Becerra 5t

[@gdavis8588]

Will this work if the bearing wall/beam is offset about 3 ft from the ridge? Could I drop some verticals from the purlins to the joists to support them?

[@gregvancom]

Purlins and structural supporting braces can sit on top of anything that will support their load, including the proper sized ceiling joist. Something else to consider would be to install some type of support beam to carry the load if possible.

[@gdavis8588]

@@gregvancom I might try to send some photos. I've tried to get an engineer to inspect but they don't want to drive 100 miles to get to my house.

[@Jay-tk7ib]

If you don't have a wall on which to set your purlin braces, you can set them on a strongback, right? I suppose it's different for different areas of the country. Good video.

[@gregvancom]

Not really, because it would put additional weight on the ceiling joists, but you could do it if the ceiling joists were designed to support the weight in that manner.

[@Jay-tk7ib]

Right, but a strongback being stiffened, and blocked up on the ends, it doesn't put the entire weight of the purlin wall on the ceiling joists. The ceiling joists can be oversized, as well. But you're right, it would add weight to them.

[@gregvancom]

I've seen plenty of projects where construction workers put purlins on top of ceiling joists without any problems, but this isn't suggesting that it will work all the time.

[@Jay-tk7ib]

Yeah, every situation is different.

[@johnabovyan829]

👌👌👌👍👍👍

[@kamotengkahoybilanghoy9248]

we use purlins to where roof sheet is nailed.

[@gregvancom]

That works.

[@holton345]

Great vids. I subbed, liked, and bookmarked your website. I have some photos and questions for you that I will post in the near future. I *think* the photos will be fully self-explanatory to you. I intend to get a structural engineer out here sometime soon, but I just want some preliminary information as my 1937 house has purlins, but they are not installed correctly and seem almost haphazardly placed, some on the tops of load bearing walls, but many are not. If you would be willing to look at my photos maybe you could tell me what is up with my house. It is that funny construction using shiplapped planks throughout, internal and external walls, the floors, the ceilings, and the walls have the planks set at a 45º angle. I know this is supposed to spread the downward force of the roof toward the ground like buttresses or some such (or so I have been told). If this is not nonsense, if it is actually a structural feature, it seems to me that to replace these planks in the walls with OSB might weaken the structure. I know - I have no idea what I am talking about, but at least I am interested to learn and *know* I speak from a position of ignorance. :-) If you are willing to look at five or six photos of my attic and answer a few questions I could make some actual plans and see if hiring a structural engineer would be a waste of money and time because what I want to do is just not going to work. If this home had been built with more modern techniques I would have fewer issues understanding what is what. Hoping to hear back from you. I could give you my email if you have a Contact Me system on your web page. Hope to hear from you soon. Your videos are well produced and very informative. I see light at the end of the tunnel. Or something like that, heh, heh... Thank you for the information and for your time reading this comment.

[@gregvancom]

Send the pictures to me and I will check them out. My email address can be found at our website, simply go to the bottom and look for contact. Thanks for liking and supporting our website.