ᐅ Structural engineering for a prefabricated house using timber frame construction

We are currently planning to build a single-family house with a prefab construction company using a timber frame method.

Now to my question regarding the structural engineering: we want the upper floor to extend over the ground floor in the terrace area. It is important for us that this can be done without any columns (i.e., no columns in the terrace area). The planner has told us that this will not be possible without columns.

So my actual question is: Is it possible that this is more feasible structurally with solid construction, meaning masonry, or is there no significant difference between timber frame construction and masonry in this regard?

Perhaps someone can help us out here.

Best regards

@joho78, regarding this design:

There is an overhang of approximately 3 x 12 m (10 x 39 ft) to the "left," and about 1.5 x 9 m (5 x 30 ft) towards the front, that is, facing the viewer.

I think this will only be possible if substantial reinforcement is built into the floor structure of the upper floor. However, I am not an expert.

Didn’t you mention that your brother-in-law or someone similar has built something like this before? How was it solved there?

Hello!

This is about the design that is currently with the technical department of the prefabricated house manufacturer for a more detailed review and technical assessment. What is certain is that it won’t work without supports as it is now. My brother-in-law had a column added inside, in the corner of the living area, which I also don’t like.

The reason I’m asking: I am basically still flexible regarding how far the upper floor projects, for example, instead of 3 meters (10 feet), it could be only 2.4 meters (8 feet). I’m curious if anyone knows whether using solid construction (e.g., concrete or masonry) can achieve more than timber frame construction, or if both building methods have the same limitations concerning the reinforcements in the ceiling/floor that you mentioned.

Technically, this is not a problem. Regardless of the construction method, steel beams can be used, for example. It ultimately comes down to the effort, costs, and especially how bold and experienced the structural engineer is.

There are structural engineers who calculate smartly and manage to save a lot of unnecessary reinforcement (in solid construction), while others take the easy route and add a few tons of extra “safety steel.”

Since you cannot choose your structural engineer, you will probably have to try to persuade the engineer working for your builder.

That sounds promising. We haven't had a conversation with the company’s structural engineer yet, only with the planner so far. Since they are now digitizing the current plan version and creating a clear 3D model, we will take a look at the column solution and then have a discussion with the structural engineer.

Thanks for the comments!