Hybrid TimberFrame Question?

RickB · February 16, 2011, 01:36:38 PM

Hi all, new to forum.

Looking to build my own home, right now getting basic design and layout of what i want. Going to do most of the labor myself, getting help in some areas. My question is would something like whats in the 2 pictures below work, with half the house being timber and other half being stick framed with the roof going from one to the other. The timber side would be the living room and kitchen with a loft running along the back above kitchen overlooking the living room. The stick frame would be a 1 1/2 - 2 story kinda going from 5 foot under eve on 2nd story tying into roof from timber frame. Is this something that could work or do i need to start looking at different options?

Jim_Rogers · February 16, 2011, 03:54:02 PM

Until you add more timbers so that I can fully see the design, it's hard to say.

One of the most determining factors is the placement of the timbers that are going to shrink when they dry out.

If you don't compensate for this shrinkage you're going to get gaps, and may cause roof leaks and other problems.

RickB · February 16, 2011, 06:15:27 PM

Here's two more pics showing more beam placement. At this point tho the design is flexible. Really just going for the open look and exposed beams in living room and kitchen areas, and view from loft to front of house to be open and unblocked for most part. I added these beams going more for placement , leaving open areas and spaces more then any kind of load bearing or structural support so they might not work as placed.

About timbers shrinking, and possible roof leaks, would doing it this way be overly complicated and a lot for someone new to timber frames? I offset beams from outer wall enough to allow for a normal wall frame leaving all the timbers inside the house, would that help some in those areas?

This started out as a normally framed house without any timbers or other stuff. Then once I really thought about what I wanted, the open design of timber framing and look of the exposed wood starting looking better and better. Would really love to just go with full timber frame for whole house, still might in the end.

Thank you for taking time to answer questions.

Jim_Rogers · February 16, 2011, 06:19:53 PM

It is the connection between the timber framed parts and the regular stick build stuff that is important to prevent gaps.

If you're going to stick build over everything shown and the timbers shown are not going to be structural then that's one thing. But if these are going to be there, then they might as well do something, like hold up your roof.

add more please.....

RickB · February 17, 2011, 09:15:16 AM

I wasn't clear in what i meant, in the end all the timbers need to be fully structural and load bearing. I only meant the way there are placed now in the pics. I drew those in not really sure of how they need to be placed or where. I didn't measure anything other then can the lower horizontal beams be walked under and will they allow enough room for the loft to be built on in the back of house. And in a way that would keep me from having an A-frame on the timber part with the stick frame butting up to it under the end of it.

Here's a few more pics, showing roof connection and kinda what i mean. Not sure any of this will work tho.

In these the outer wall on timber side is built up, using stick framing, sips, or something. At the top some kind of truss going across front. After that run the trusses so that they butt up with and sit flush with ones on timber side, both 24" oc ?

Jim_Rogers · February 17, 2011, 10:05:05 AM

Here is what I see, at this point, in the red circle where the arrow is pointing is going to be a problem.

The timber rafter is going to shrink, vertically and the 2by rafter is not going to shrink the same amount.
This is where the gaps will develop....

RickB · February 17, 2011, 03:21:04 PM

Yea, that wasn't something I thought about, and never had to deal with. I'll have to take a closer look at it and see if I can figure something out., or change to different design.

How would something like that be handled in whole timber frames. If two rafters meet at that point and both of them, or the beam holding them up shrink, wouldn't that also do some kinda damage to the roof above them?

witterbound · February 17, 2011, 05:00:31 PM

What are you going to put on the outside of the timber frame part? My hunch is that in this kind of house you might just put a regular stick framed wall outside the timber frame for insulation, studs for sheetrock and siding, etc. That decision will affect a lot of other things, and may help overcome the problem Jim is talking about. Dunno, it's just hard to think just about the frame when designing IMO.

RickB · February 17, 2011, 06:14:13 PM

Planned on just stick framing the walls up around the timbers, right now there's a 4 inch gap between timbers and the outside edge, when finished the timbers would sit flush against the drywall fully inside the house. The beams running along the 2 story stick framed area are offset 1/2 inch to allow them to sit flush with drywall also. The two beams running along the right side of stairs will be sitting flush against a wall also, its just hasn't been added to the model yet.

Been looking at sip panels, might use those instead of framing walls.

If this design looks like it would be complicated, it might be easier for me to just change designs. Just going for open look and exposed wood of timber frame in two main areas, living room and kitchen area. The loft was just thrown in since wanting other part to be 2 story, space was there might as well use it.

witterbound · February 18, 2011, 09:25:56 AM

I believe, that timber frame hybrids are more often designed so that the timber frame part could be a free standing little home, and the hybrid part is tacked on to it. In your model, if the timber frame was a stand alone, you'd have a shed roof. It's more common, I think, to have the timber frame a regular pitched on both sides roof. In other words, in your model, the timber frame would be on the left side, not on the front side. Then the stick framed part would be on the right side. You would offset the rooflines a little, because the timber frame part will probably settle down a tad, and it prevents the problems Jim mentioned above.

Jim_Rogers · February 18, 2011, 11:18:39 AM

Quote from: RickB on February 17, 2011, 03:21:04 PM
How would something like that be handled in whole timber frames. If two rafters meet at that point and both of them, or the beam holding them up shrink, wouldn't that also do some kinda damage to the roof above them?

In a traditional frame the two timber rafters would be connected with a simple tongue and fork joint.
The support would/could be just at the plate at the wall. If you wanted support at the ridge then there would be a ridge beam, usually dropped down below the rafters and the rafters would sit on it.
We have had several recent discussions about ridge beams, some supported some not.
When everything is timbers then we hope that all shrinkage is the same and that everything will settle down evenly.

RickB · February 18, 2011, 12:33:20 PM

I kept seeing something wrong in that design why I posted it here just couldn't tell what it was. I had it backwards. It started out as normal 2-story that got chopped up trying for the open look and space of a timberframe. From whats posted here, gonna go back and start over using free standing timberframe as base and build off it. Maybe with this I will be able to use more of a true timberframe while keeping a simple (if you can say that) design. Thanks for the info.

Think my brain went on strike since starting this project of building a house. But rather have all my problems now, before any building actually starts.

Jim_Rogers · February 18, 2011, 02:47:15 PM

We'll be here to look at the next version when you have it ready.....

barbender · February 18, 2011, 03:36:04 PM

The house I am building, I stick framed it and used timbers for the ridge beam, second story floor support beam, and supporting posts. When I'm done, I think I'll trim it out with rough cut 2" stock to make it look timber framed. "Fuax" timber frame ;D. I love the look of timber frames, but so many of those types of structures it seems that they are built twice- 1 the frame, and 2- the structure that houses the installation. When using SIPS for example, a SIPS house can be freestanding, no need for a timber frame support. So in my mind, the timber frame structure becomes very expensive trim at that point. Please understand, I'm not knocking timber frames either, I love them, they are so beautiful. It's just the methods I've seen for insulating basically build another structure on the outside of the frame, so I decided to use more of a timber accent kind of theme.

witterbound · February 18, 2011, 04:30:43 PM

Barbender, I think you're basically right. The only cost the timberframe saves over the cost of a stick frame home is that the timber frame supports the roof, so you don't have to stick build your rafters and stuff to support your roof.

barbender · February 19, 2011, 11:30:27 AM

Right, and you can get SIPS with I joists in them that are self supporting. I helped a guy with an all SIPS house, it had a glulam structural ridge beam, otherwise 100% SIPS panel without any other support.