Engineering Analysis and Stamp

I have completed a twenty page LayOut drawing package for our new home that we’re hoping to start building as soon as possible. It is an unusual structure that will require a little more complex engineering analysis. Engineering firms here in Nova Scotia Canada are really busy these days with a massive building boom and are reluctant to take on anything out of the ordinary.

I am looking for an engineer willing and able to provide us with an engineering stamp on our drawings. We require this before a building permit can be issued. I have attached a screenshot of our project for the interest of any engineers within the SketchUp community that might be able to help.

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Boy that looks cool.

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Thanks… we’re really looking forward to starting construction. I do realize that Sketchup is an architects playground, but I was hoping that there might also be some engineering types within the community. But I haven’t received any offers from any engineers, so maybe not.

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@Earthling, you might have more luck if you would provide additional information about number of floors (level heights), internal span (any columns allowed?), at least some info about its dimensions.
Right now it’s an impressive (cool) design, looking upon its outside

And what is it going to be built on: rock, soft swampy ground, you name it?
(My house is built on reinforced concrete 15 piles, average 17m in length. No one will ever see them again (I hope))

Thanks for the suggestion. I was thinking/hoping that the concept alone, might be enough for an engineer to show interest, but yeah maybe more details would earn more interest.

The structure is based on a three frequency icosahedron. Geodesic domes are based on a single sphere with a single radius. This design is comprised of five partial spheres with five radii from a common origin, 14’, 17’ 20’, 23’ and 29’. There is a lot of bedrock in the area but am not yet fully certain that we won’t need a minimum footing depth of 4 feet for part of it. I have drawn full foundation plans to be used as needed. Level one is 1,417 square feet, and is comprised of a two car garage, and a large workshop and storage area. Ceiling height is 9’ on this level. Level two is a 1,045 square foot living area. There is a supporting structure of post and beams that support the level two floor. Also, ten of the hubs are tied in with metal brackets to the level two floor. Most of level two is open to the structure which measures 27’ from the level one floor to the highest point. There is a small loft above part of it. We are planning to design and build a main structure of similar (but different) shape and a connecting passage within a couple of years of phase one completion. The five local engineers I have spoken with so far are either too busy or do not have the capacity and means to do a 3D structural analysis using a SketchUp model. This is why I’ve decided to expand our engineer search to within the SketchUp community.

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Clearly you need someone licensed in Canada if not specifically Nova Scotia. (In the US, licensing is state specific) If this is mass timber construction, it would be good to have someone familiar with that. You could look to fabricators for timber construction too as they may have their own in house engineer. When I did a hybrid timber frame barn addition with Benson Woodworking, they had their own in house engineer to do all the timber frame engineering.

You may want to hire a geotech company to drill test borings on site to see if the hit ledge and where. I did that on a current project, and my engineer is telling me you want to avoid being part on ledge and part not.

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I already have the geotech analysis lined up, with the hope that we’ll get a concrete foundation plan (pun intended) in the next few weeks.

Our permit office would like to know that a structural analysis has been done, which I was told could come from an engineering firm anywhere in the world. They are not so concerned about where the engineer is licensed, provided that the local building code is adhered to.

It looks like I may have found an innovative engineering company from Toronto that specializes in unusual structures. It is starting to come together!!

I am a timber engineer… My heart ist jumping! This is a very cool project and I would really love to be part of it unfortunately I am only working part-time and only in the area southern munic)…I constantly hear from timber engineers out of italy (insta and mailinglist news of them), they realize timber projects around the globe. Perhaps it makes sense and they are licenced for your reagion too:

good luck

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To the best of my knowledge, in Canada, you need to be licensed by province. When I was an active mechanical engineer, I was licensed for Quebec, Ontario and New Foundland and Labrador.

For your project, the engineer will most certainly need to be registered with “Engineers Nova Scotia”. You can find their Web page by googling the text between quotes.

Messr. Millette,

If the local jurisdiction where you are applying for a building permit is requiring that your plans be stamped by a registered engineer, then RTCool and Jean Lemire have it exactly correct … you need to find an engineer that is registered in Nova Scotia. In the US, engineers (and architects) must be registered in each state in which they practice … and evidently Canada is similar (engineers are required to be registered in each providence in which they practice).

From your initial post it sounds like you may have already contacted some local (Nova Scotia) engineering firms … and they told you they were too busy. I submit that may be only part of the story.

  1. Many engineers do not like to venture outside their area of expertise. They have tool sets and work flows for very specific types of analysis … and it is simply not cost effective for them to accept jobs that do not fit their practice.

  2. With that mind I submit that you might have more success if seek individuals/firms that specialize in timber frame construction. And when you approach them be prepared to show them not only your plan set … but also your calculations for beam sizing … and your analysis of the loads on the various beam joints. If all that is in order they might see their way clear to accepting the job.

  3. And it also occurs to me that when you contacted the engineering firms originally you may not have been specific enough about which portion of the plans need to be stamped. In the US (for personal residences) it is not uncommon for a local jurisdiction to accept unstamped plans from the home owner … but still require stamped plans for the foundation and septic system … and perhaps electrical (for example). This is particularly true if the construction is conventional platform framing … which clearly your home is NOT. But even so: Is the local jurisdiction requiring your entire plan set to be stamped? … including foundation, structure and MEP? Or … are they only asking for a stamp on the foundation plans (for example)? If they want the entire plan set stamped, clearly that is a non-trivial job on a geodesic dome structure … with non-trivial liability exposure for the engineer.

So there you have it … good luck with your endeavor.

Regards,

E. Godsey, P.E. (inactive)

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Thank you all for taking the time to respond to my post. Discovering how difficult it is to get an engineers stamp for these drawings, has been an uncomfortable and mildly stressful realization. I do have some genuine interest but no firm commitments yet. Hopefully, I’ll get that sorted out this week.

Mr Godsey, I think that you are spot on with your thoughts on why I’m having a problem. I’ve had a couple of firms come right out and say that that they are not equipped to do the required analysis, and that they couldn’t even begin to quote a job like this.

I could have been a lot clearer in my initial post. I was and still am hoping to get the structural analysis and any calculations done by any engineer, anywhere in the world, with the hope that a local engineer would then be more inclined to work with us. To this end… thank you for the information in your response Mr SPB. I will reach out to ergodomus today.

I have never done anything like this before (meaning designing and building a house of any kind). And you are correct. I do not know which portion of the plans need to be stamped. I had made the assumption that the permit office would require a stamp for the entire construction package. I will get the answer to that question today.

I’ve truly enjoyed the process of learning SketchUp and LayOut. Both of these platforms are truly incredible architectural tools. I do understand that this is a complex structure requiring an exceptionally complicated level of engineering, and we anticipate a higher (perhaps significantly higher) associated engineering cost. Somehow or other though, we have to get our drawings stamped. There is far too much time and effort (on my part) to just give up on it. And it has been a life’s goal to one day build and live in a dome structure. Hopefully we’ll find a firm over the next few days that is prepared and eager even to take on this non-trivial job with non-trivial liability.

Here is a dropbox link to the entire project for the interest of anyone who might be interested.

Thanks again for all the helpful responses.

Michael,

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Regardless of the engineering issues; with all those concave junctions of your dome roof and skylight planes your really are going to have some complex junction waterproofing details… and maybe the insulation requirements in such a cold climate…( not my area of expertise coming from Australia and Vietnam :slight_smile: )… Geodesic domes get their cost, construction and structural efficiency from the simple repetitive nature of their elements… the complexity is usually inside the dome…

just a quick search of geodesic domes shows how rare anyone complicates the pure geodesic form…

In design the original conceptual approach is the most important decision you will make and the hardest to fix if you get it wrong… unfortunately it is the concept design process that is the least valued by most clients…

Don’t want to be a debbie damper on your design… but it is a lot easier to review it now rather than during construction…

PS, I downloaded your SU model… it is very impressively organised and detailed…but I had trouble isolating the primary structural elements in the design… and given the unusual form, ( exploded geodesic dome with fragmented dome surfaces linked by perpendicular planes eg skylights) so maybe preparing a document set just highlighting the structural concept and elements will help get an engineer on board…good luck

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Hello GS… thanks for your interest and comments. I have thankfully, managed to find an engineer to work with on our project. I have provided them with a vector drawing of the structural elements for their analysis software.

My initial approach, when I designed the conceptual model, was to intentionally have no regard to the interior complexity or structural integrity. My focus was entirely on creating an interesting looking exterior shape (initially). Then I worked on the integration of form and function, and most importantly, creating a structurally viable building. The posts and beams supporting the level two floor are important structural elements as the level two floor is tied to the external dome structure through ten hubs (each one adapted with a bracket as required). I realize that messing with the integrity of the geodesic structure will compromise its inherent strength, which meant that I was going way out on a limb with this design… with the hope that it could be made to be structurally viable.

The structural elements are detailed in a few of the LayOut drawings within that dropbox link.

And yes, insulation requirements are also very important. It is our hope and intention to use closed cell expanding foam insulation using the code requirements for roof insulation (as opposed to walls) as the minimum throughout the structure. There is sufficient cavity in a nominal 2X8 frame to satisfy local code requirements.

We are planning on breaking ground in the spring and hoping to be living in our new home by this time next year. I’ll post a few construction pics as we proceed. Thanks again for your response to my post.

Michael,

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Whenever I take an engineering project (Washington State only) I also have the stipulation that it is within travel distance for me since I like to get on site and inspect the work to make sure it is up to a high standard. The best well laid plans are often muddled when the actual construction becomes a hack job.

Another reason to get a local engineer is also in the case of mistakes made by the contractor and then an on site inspection is required to determine the fix or alternate solution.

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Yes I agree… am relieved to have found a local engineer. It is a busy time for engineers here and they didn’t have the resources to dig into anything unusual. I did find one Toronto firm who would get a local engineer to work with for site surveys… but I am happy to report that we’ve found someone locally, and who has experience with unusual designs.

I’ll be the general contractor, the building contractor, the electrical and plumbing contractor and the painter and flooring guy, so I won’t have anyone to blame but myself for substandard work. I think I’ve got a pretty solid bullet-proof plan for getting the structural framework built to a high precision. With this critical step completed, the rest should be easy. That’s the theory anyway… with a few timely visits from the engineer and building inspectors. What a process!!!

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Hi Michael,

Wishing you all the success… it is an impressive model, particularly considering your background an recent adoption on SU… you seem to have thoroughly considered the implications of your concept … many times I have encountered designs that have been designed with function following form… with horrendous compromises… it is a real challenge to do that efficiently.

Look forward to seeing site photos :)…

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Greetings @Earthling ,

Very interesting project you are building!
It’s my dream to build a dome house for myself one day.
I stumbled on this thread just now and I remembered seeing an exploded dome on the internet before…
Here’s a link: kristoffer tejlgaard + benny jepsen: people's meeting dome
I’m interested in seeing the progress of your build as are others here!
Greetings from the Netherlands!

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Good morning Tweenulzeven… thanks for your interest in our project and the best of luck to you, in your own dream to build a dome home. That People’s Dome in Denmark is a beautiful structure indeed. I wonder what the inspiration was for those architects. In my case it was a light fixture in a jewelry store. There was a 2’ diameter framework of a 5 frequency icosahedron and then another 5 frequency icosahedron that was only one inch or so larger. LED’s connected the two spheres at each vertice. This idea of expanding spheres led me coming up with this idea. I knew nothing of SketchUp at the time and proceeded to build a conceptual model with 1/8" aluminum tubes and pipe cleaners to hold them together at the vertices. Discovering SketchUp and how intuitive it was to use, transformed my ideas into a 3D model and then LayOut plans.

I wish I could report that we are now living in this dream home but there has been unanticipated delays, not the least of which is finding help in this building boom in Nova Scotia, Canada. This will be the first home I’ve ever built but I’m no stranger to the construction industry in general. With a little bit of experienced help from a friend, I was able to build the footings. Now we are finally on to the next stage of the project… the 18" high foundation walls. Here’s a picture of the footings with the forms removed. I’ll post pictures as things develop.

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Delighted to see the first fruits of all your preparatory drawings and getting planning permissions.

Good to see that you started with the build!
I understand that it is hard to get good help these days. It’s the same over here in the Netherlands and probably a lot of other countries.
Please keep us updated on your progress!!
Good luck with your beautiful project!