In the midwest, we typically do this for small roof top mechanical equipment. Anchoring through the roof results in penetrations that are prone to leaks and require more frequent maintenance. I've never heard of one moving problematically let alone blowing off the roof or tipping over. Yet an...
This is helpful. I can likely reduce the snow load with the assumption that it will remain heated since it is a greenhouse. That does not help with wind loads which are resulting in the base members to be overstressed. Tie rods don't help much in that case either. Perhaps the flexibility of the...
I originally had them both pinned, but changed them to both be fixed as they are typically set in concrete like a fence post. Of course this helped with deflections but not strength.
I had a client come to me for structural analysis for hoop houses he's been building for nearly a decade with no problems. He will be using them in a situation where it will no longer be considered a temporary structure. Because of this the jurisdiction is requiring calcs showing it meets the...
I'll reach out to a manufacturer. I suspect 18" deep trusses at 16" OC for residential floor loading (40PSF) is doable, but I worry about deflection/vibration.
I'm still also very curious about 12" truss spacing and the practicality of installing ductwork. I'd be curious to know if anyone has...
I don't think I need to go to extremes to maximize the spacing between joists. I would have been comfortable with a more common 16" on Center spacing. I see plenty of 16 in deep trusses at 16 inches on Center with ductwork running in it. I'm sure 18 inch deep trusses have plenty of space but I...
I plan to use 18 inch deep trusses so they should be reasonable for the span. I'm just concerned about the difficulty getting utilities into the space. The owner would like to use trusses specifically for that purpose... To avoid the need for soffits.
Does anyone here have experience using wood floor trusses at 12" OC? I have 26'-0" spans and the only way to get that to work with my depth restriction is 12" OC. I'm hesitant because I feel like it will make using the space for utilities very challenging - especially duct work. This is for...
I appreciate the suggestions KootK.
1. I have already reduced the live loads to the maximum extent.
2. I don't see how that could be done considering the top plate would need to be installed before placing the podium slab.
3. We're too far down the road in design to do this and it wouldn't...
Yes, the columns are heavy, but they work. I am trying to avoid contributing anymore lateral load to the stair towers than what's already there. Plus, it's a long span for that diaphragm so I would be a little concerned about the deflection with the cumulative lateral loads at that level.
I am working on a 5 over 1 mixed-use building with a composite steel podium. the 5 stories above are CFMF. The bearing walls align with the column lines. The resulting gravity loads are very large and the beams are quite big: up to W40x211. The upper floor diaphragms span laterally to the CMU...
I am working on a residential addition. The new floor framing will be higher than the existing by about 8" to 12". If it wasn't, I would just remove the rim joist, run the new joists over the existing wall and install blocking. But I don't want to interrupt the sill plate. Would it make sense to...
This isn't my detail. It's from a website of a company who specializes in adding basements to homes.
How do you handle the hinge in the wall when underpinning if you don't use dowels?
Thanks for the suggestions. I suspected doweling into the existing footing would be required in some cases. I wonder how often it's done without dowels.
This particular contractor is a piece of work. He had a low bid and it stated that it wouldn't be constructed per drawings but it would work. When the owner asked for clarifications on what he would provide (per my suggestion) he said bars at 24 in on center each way. Didn't even give a bar...
It's nice to hear that I'm not the only one dealing with this. It's not great to hear it's so common. My experience is mostly in commercial and industrial. Residential contractors apparently want to use the bare minimum.
This is not my typical experience with contractors, but yes occasionally I come across a gem like this guy.
It's a pretty large home. I think between my final revision and what he wants to install, maybe $5-8k. Well worth it in my opinion.
Thanks for the response. Although I have experienced that scenario many times, this is a bit different. Contractors are bidding on the work right now. A particular contractor is trying to be a hero and save the owner money by claiming he can place this 10'-12' wall with #4 @ 24" OC EW because...
