Complicated Conventional Wood Framed Roof 1

Standard American · Oct 12, 2022

I have a residential project where the contractor does not want to use wood trusses because of the long lead time. He is insisting I change my design from wood trusses to conventional wood frame but I just don't see how it will work with the roof geometry. I have made several attempts to try to lay out the framing but just don't see anything that is practical. He is also insisting I keep the member lengths to 16ft too so he can go to local lumber yard and pick up what he needs. I attached an image of what the roof profile looks like. Do you think it would be out of line to go back to the architect and tell them to simplify it because it's not practical to conventionally frame or am I over thinking this? Keep in mind this is the architect's version that they thought they simplified it already. Just a little back story the low roof on the right is existing and they plan to raise it in another phase. Thanks for the comments.

atrizzy · Oct 12, 2022

This roofline is the result of the architect expecting to use roof trusses.
If the architect learns that the contractor wants to go to stick-framed, I'd expect that they would want a kick at revising the roof design with that in mind.
It doesn't make sense to have a roofline like this without the use of trusses.

driftLimiter · Oct 12, 2022

Just looking at it quickly it does look difficult to layout framing with ridge beams and rafters, IDK about impossible but definitely complicated. I am also curious how this change might effect the ceiling and insulation. Simpson makes some pretty nifty connectors to frame valleys and hips with. It isn't your fault that the builder can't get trusses in time, push this back to the arch, and they will probably press the owner/builder to make it work as designed or you and the arch can both go through redesign together.

jayrod12 · Oct 12, 2022

I agree with this roof profile not being possible with conventional stick framing without some substantial interior load-bearing type walls. On complicated roofs from before trusses were commonplace it was common to use the ceiling joists to support the roof rafters in many locations.

KootK · Oct 12, 2022

Get a copy of this. You can hand frame almost anything if you want it badly enough.

Standard American · Oct 12, 2022

Thanks for the reply but this is the result after the architect revised the roof for conventional framing. I put in a call with them and they are going to review with the contractor and get back to me. I suggested having the ridge from the garage extend straight to the back wall then frame the two areas on the northwest area of the image into the ridge with a simple gable or hip. Eliminating that weird partial gable where new meets old.

Standard American · Oct 12, 2022

@Kootk thanks for the reference, I'll check it out. I have no doubt anything is possible but what's practical and buildable is another story. The guys doing this would be guys that normally set trusses and build partition walls not some master craftsmen.

dik · Oct 12, 2022

Wow... just because you can do something, doesn't mean you should.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

KootK · Oct 12, 2022

I feel as though we pretty much have to trust our contractors to tell us what they feel is practical and buildable. If you have little confidence in yours, then perhaps you:

1) Say that this isn't the kind of work that you're not great at and ask them to find someone else or;

2) Charge a generous lump sum for a schematic design that they review before you proceed and ask to be paid T&E for your contract administration if it goes forward conventional.

It's somewhat amusing that, in many markets now, "conventional" framing is anything but.

KootK · Oct 12, 2022

I really don't see what the big deal is. Roof typologies of this sort existed long before pre-engineered trusses did. Trusses were developed specifically to mimic hand frame solutions. Yeah, you'll need some additional bearing walls. So what? It will be up to the other project team members to decide if that's a worthwhile tradeoff.

jayrod12 · Oct 12, 2022

KootK said:
Yeah, you'll need some additional bearing walls. So what? It will be up to the other project team members to decide if that's a worthwhile tradeoff.

This is where I usually win the argument with the client/arch/contractor. Sure we can absolutely do what you want, but I'll need this wall and these other walls to be load-bearing. Therefore they'll need to be supported via beams, oh and these ceiling joists all need to be 2x6 here, and here they need to be 2x8.

Once they factor all of that in, often they'll just go with trusses. But if timelines for delivery are truly that bad where you are, they may go for it. I usually make sure to indicate that there are additional fees associated with the change since it changes not just the roof but also the floor framing.

KootK · Oct 12, 2022

@jayrod12: exactly. One of the best business mentors that I ever had was fond of saying "we don't tell clients 'no', we tell then 'yes but'". "Yes but" amounts to no in many cases but is, generally, a good way to say "no" if having clients is important to you. That said, I would love to hear the tale of OP telling his contractor "You guys are a bunch of Yahoos and there's no way that I'd trust you to do this". Video or didn't happen...

I do understand that OP is not actually proposing saying that.

Standard American · Oct 12, 2022

The contractor is saying 6 months+ on the trusses but the bad thing is I finished the drawings in July so he could have been half way there by now. This changing to conventional just came up last week because he wants to start the project this week. I was taught the same thing of never saying no and providing an alternative solution. I was just looking for a sanity check on complexity of the roof profile with conventional framing.

XR250 · Oct 12, 2022

"It doesn't make sense to have a roofline like this without the use of trusses."
Nonsense. I mean, I don't think a roof line like this makes sense at all and is dumb looking.

However, in my neck of the woods, this type of roof would be stick framed more often than trussed. Will require interior walls to be load bearing and can be a hassle to chase the loads to the foundation. Not my favorite type of job, but I charge enough to make it worth my while.

jayrod12 · Oct 12, 2022

Standard American said:
This changing to conventional just came up last week because he wants to start the project this week.

Sounds pretty par for the course to be honest. I would make sure the client is aware that you redesigning the roof will incur additional fees because you completed the design in July as required under the original fee agreement. Don't do this work for free.

Aesur · Oct 12, 2022

I would start by making sure the architect knew about the requested changes, normally they are your client, not the contractor. As for the layout, it's definitely doable, but not efficient, essentially you will be starting all over on the project. You will need beams, columns and many interior walls to be load bearing and could run into some of the interior walls becoming larger studs due to wall heights. Foundations will be affected, overall I believe this approach could increase costs compared to trusses. Additionally if uplift is a concern, you now have less trib area and therefore higher C&C wind loading. We recently designed a house with a similar roof structure where they wanted vaulted ceilings with thin profiles and we made it work by grabbing most interior walls, adding columns and beams along ridges, valleys, and anywhere else needed; it will be fun to build, but was the only option without trusses.

phamENG · Oct 12, 2022

I'm with XR250 on the terrible look of this thing, but it's not hard to do. It's a single story, which makes things easier. It looks like a slab on grade, which makes things easier again.

As others have mentioned, you'll need to add some knee walls in the attic, increase some ceiling joist sizes, probably add some beams in the ceiling, and make more walls bearing/add columns with foundation elements. But it shouldn't be too hard. Charge hourly with a warning that they are having you redesign the entire gravity load supporting system and likely some collector/drag elements in the roof for the LFRS...so the fee will be pretty close to the original design cost.

Uplift load paths can get tricky here, too. Pay close attention if you're having to break up rafter spans.

JStructsteel · Oct 12, 2022

"Yes, this is certainly something I can do. Reach out to the architect as they are my client and they will get the change in motion, I will work out the new contract terms with them"

Brad805 · Oct 13, 2022

I agree with JS. Step 1, sort out cost of engineering. I would guess this solution would be 4* the engineering of a typical truss package. Endless details to field frame that, and if your framer is not top notch that will lead to endless RFI's.

Did they mention the delivery time for trusses? If >8wks then maybe I would agree with the GC, but if not, I would push back.

The suggestion to limit the wood length to 16'-0" seems silly. Even in my little area I can get many different TJI's in very short times. Truss delivery times in our area vary now from 4wks to months.

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