Experimenting with a Combination of Timber, Window Wall & SIPs

[tjcaine]

Greetings all,

My name is Tyler and I am an architect living and working in New York City. I recently started my own practice and one of the "pet" projects I've been working on in the off time is a theoretical house design that is experimenting with timber and SIPs. It is this project that brings me here today with the hope that the wealth of knowledge and experience in this forum can help make sure I'm not too far off the beaten path of reality in some of my assumptions.

Full disclosure, the vast majority of my design work has been in urban areas, so while I worked in construction for a while and love building things, I have no timber framing experience!

So the project... The goal of this design exercise was to design a house that is small and flexible in its use in the sense that parts of it could be powered down when not in use. Ultimately, the house could hopefully be resource neutral with a tight envelope, geothermal heating and cooling, and solar for hot water and power.

Enter the house. The house works off of a series of frames that could be erected on site to support walls and floors of SIPs panels. A fair amount of the exterior also includes high-performance window wall. As you will see from some of the diagrams, it is not a typical timber frame per se, but uses a primary and secondary frame system that are each a kit-of-parts. Overall, the design is still in what I would call the beginning of the Design Development [DD] phase and includes no formal review by an engineer (since I am the acting client).

My questions are really whether or not the member sizing I am using for the timber components are within the realm of reasonable.  Could the attachment for the primary system be a split ring connector? For the secondary system, is it feasible to use a knife plate on 4" wide members? I realize that some of these applications are atypical, but given the breadth of knowledge on the forum, I was interested in what some of the reactions would be.

Attached, you can find a PDF including some different images including a view extracted from a SketchUp model along with a series of diagrams meant to explain the structural systems and how they work. I have some plans and sections I can follow up with if necessary in various stages of development. 

Many thanks in advance to any thoughts you might have!

[Seaman]

I cannot help with your question, but WELCOME to the FF !

[Roger Nair]

Hi Tyler, you are pretty far afield from braced frame technique.  It appears to me that your frame will need to hold it's shape by means of stiffness of joints, which, in general, is not suitable for concentrated arrays of steel fasteners in wood.  Without shear panels or bracing, I fear that racking loads would be transferred to the glass panels.  However, the people who work with glulams might have developed systems that would conform closer to your intent.  Good luck and good fortune.

[Ljohnsaw]

Welcome!

Interesting concept.  Never thought of using SIPS for flooring.  Didn't know they were rated for that.  Might be too industrial for you but perhaps diagonal turn-buckled guy wires or rods for lateral support?

[tjcaine]

Roger & John,

Thanks for your comments. The diagrams I was showing were isolating some components for the prospect of load bearing, but the frames will get some help in the bracing against each other from the solid (SIPs) wall on the north side (opposite of the glass). Here's a partial plan of the ground floor. I imagine you're talking about the frames racking in the north/south direction (the width of the house)?




 

[tjcaine]

One could also hide shear panels in that direction in some of the interior walls? If counting the posts from left to right in plan, I could see shear accommodations strengthened in lines 2,3,6 and 12 that run parallel with the frames.