Upper rafter extension?

New to the forum and have a question for you guys. In these pictures you are looking at an extension of upper end of two rafters… What is yalls take on it? Homeowner didn’t seem to concerned about it since it has been like this for 20years.

It’s a pretty thick piece of wood…old fashioned way of doing it…it doesn’t look like it’s failing…better to scab it both sides with 1/2" or 3/4" real plywood and glue and pepper nail it…If anyone has concerns put a brace under it…

I’d check the point load and move along but what a beautiful joint (That I can’t remember the name of. :thinking: ). Can anyone help me? :grin:

V-Joint splices, I believe. I have also heard them called birds mouth splice but I don’t think that is correct.

Lazy mans ‘Double Scarf’ joint.

Here’s a 'Birds Mouth"…

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Typical V joint. https://www.finehomebuilding.com/1999/07/01/splicing-ridge-boards

I don’t think its a concern, certainly stronger than the finger jointed rafters we are seeing now days.

Thanks, for the responses.

HEY Darius!
Nice to see ya on here. :cowboy_hat_face:

The question is whether these joints anticipate all possible modes of failure, which is highly unlikely despite the nice joinery and their not having failed so far. Analogous, general rules for timber framing recommend that such joints need to be supported more or less directly beneath them, which I’d think you could safely recommend having done.

It’s actually framed kinda like a hip or valley. Looks like it’s probably OK, but it wasn’t designed by an architect or approved by an engineer. Nothing ever fails until it does. I’d report it as non-conventional, non-engineered framing that appears to be structurally sufficient but confirmation would require evaluation by a locomotive engineer. Mention whether you saw any signs of failure."

Also, that splice is well executed, it’s nice and tight, but it focuses the load on on the apex of the V cut, meaning it’s a weak splice. A strong splice spreads the load across as much of the width of the board as possible.

Thought I’d throw this in here since it’s about splices. The scarfed splice in the upper right is killer. I’ve used that and it’s really strong.
A lot of people think a ridge splice should be located above a post, but that is a high stress point. So is the mid-point between supports The least stressful location for a splice is midway between those two points.

These images are from Architectural Graphic Standards. It’s expensive, like $80 an up, but is of book of construction images like these and explanations. Great Book!

How do you “know” this?

are you sure you’re in the right section?

From the web;
”Locomotive engineers typically do the following: Monitor speed, air pressure, battery use, and other instruments to ensure that the locomotive runs smoothly. Observe track for obstructions, such as fallen tree branches. Use a variety of controls, such as throttles and airbrakes, to operate the train .”
Make sense - train could be a moving house.

modified scarf jpoint

I don’t Frank, but you’ve been a framer. You ever see an architect draw anything like that? and… it’s possible but extremely unlikely that it was engineered unless it was done at time of sale because some home inspector identified it as funky framing.

I wouldn’t state it quite so definitely in a report, but we’re having a message board discussion. In a report, I’d say just what I mentioned in my post #11 (but maybe with a different engineer recommendation :wink:).

Simon, I’ve seen some train wrecks in this section. You can’t be too careful! :upside_down_face:

Thats typically the most stressed part of the roof , Vally jacks

Sure… :slight_smile: but I’ve also seen blueprints posted showing OP’s pictured joint with plywood gussets. Yet, you claim there is no such beast, why?

on a side note , i happen to be an ex locomotive engineer :blush:, actually my cards still good

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