Purlin braces

Okay guys I don’t want to look like a fool recommending a truss or structural engineer to evaluate. The purlin braces in this attic are notched at the top and secured with one nail to the rafter braces. Is this structurally sound?






In the very 1st picture, I see 2 nails.

How old is the house? Is anything falling down?

I doubt you’re going to find anything in writing to call it out as wrong.

Just wondering when I post on here I get 50 guys view my post and either one or none responses. No Joe I haven’t seen anything in writing. One or two nails holding the top corner of each of these braces. Home was built in 1961. I guess I’ll refer it too a engineer. Thank you Joe, at least I got one response.

Doesn’t that tell you something right there? I wouldn’t refer this to anyone unless I saw some indication of failure somewhere. I’m not aware of a bird’s mouth framing technique like that being an issue but Marcel and Kenton are good framing resources…maybe they will chime in.

I understand your frustration with a lack of response. Now…had you posted a political thread, you’d have folks all over it!

If there were no sags in the roof, I wouldn’t say anything. The house has been there for > 50 years. Depending on where you live, it has held up snow and withstood high winds for 50 years. I would let it ride if there were no visible sags.


It does not appear that the purlins themselves are large enough. The code states that the purlins must be the same size or larger than the rafter they support. They should also be installed on edge.

Do I see more purlins about 6’ behind those in question?

Patience grasshopper… The thread is only 12 hours old. Those that looked, may not have known your answer.

I personally didn’t notice anything to get excited about.

I think if the home was built in 1961. and roofs not sagging then they are doing there intended function.

They look half a** to me. I would at least note it in the report. I would think they are functioning, but they could have been installed a little bit better. For every 99 people that don’t care, the last 100th will think its the end of the world. All you can do is point it out.

I inspect in a city where probably 50% or better of the housing stock was built before codes were adopted. If I called everything that doesn’t meet today’s codes, many deals would fall through. Some of the homes are 100-150 years old and still stand quite well with minor sags/uneveness here and there.

If a house has withstood the test of time, with no major deficiencies occurring or imminent, then I don’t call them even if there are some uneveness/minor sags…these come with age.

Since this is in Florida, I would not be to concerned.
If it were up here, I would note it as a structural member not meeting the design criteria for its intendended purpose.
The bird mouth that was created was overcut and whatever load is transfered to it is drastically reduced and since the member is in compression, would most likely split the supporting member under excessive loads.
The bottom connection would be just as important. Is it on a bearing wall, or is it just nailed to the side of a ceiling joist.
The shear capacity of a 16d nail is only about 200lb’s as a # used in general, because it all depends on the depth and installation.

A full evaluation of the load on those struts should be kept in mind even in Florida. We can not tell from those pictures of the loading values subjected and all we can do here is guess.

If it lasted this long, most likely it will not go any where. Just trying to point out the train thought when looking at a connection as such.

There is a right way of doing things and a wrong way. Even in the 60’s, this was not the way to do it. :slight_smile:

When purlins are built correctly, then they will have two members (not including the bracing member going back to the load point)…of which the one giving its strength is perpendicular to the edge of the flat member nailed to the rafters.
The flat member simply gives the perpendicular one something to nail to.

The purlin should also be the same size of the rafters they are supporting.
Many framers today have no idea what a purlin is or how to install them…they simply are putting up 2x4 flat against the rafters and installing 2x4 bracing about every 4 feet…this is not correct.

hope that makes sense.


PS. Depending on the length of your bracing going back to a load point, that too may need to be doubled and/or properly sized. Framing is an art that has gone by the wayside.

Harry, with it lasting that long (since 1961) it’s apparently done the job, but as mentioned above, as per current requirements purlins should be on edge under rafters along with being the same size material as the rafters. Point it out, but I wouldn’t recommend an engineer. It’s functioning but could have been done better. I don’t believe purlins where required to be the same size as rafters back in the 60’s as I remember even in the 80’s that 2x4 purlins where used with 2x6 rafters at least in my neck of the woods.