What should I be looking at for building a steel frame building?
December 28, 2017 6:48 PM Subscribe
I am in the planning stages for building my own home and I'd like to do so out of steel instead of the traditional wood. I know there are kit buildings but for the cost of a kit and the results I would prefer to put it together myself and get exactly what I want for about the same cost. I know how to weld but what are some things I need to know/research before doing this that I may not already know?
I've already figured out that the building is going to be relatively box shaped perched on top of concrete footed pylons sunk into the ground. It'll allow for easier access to the underside of the house and will remove the need for an expensive foundation. I was planning on welding the beams together. I understand that bolting is the traditional way but I don't see why that would be better than simply welding the steel and then covering the metal with a protective paint to prevent rust. I know I'll need to focus more on insulation because the steel will act as a thermal bridge.
I've already figured out that the building is going to be relatively box shaped perched on top of concrete footed pylons sunk into the ground. It'll allow for easier access to the underside of the house and will remove the need for an expensive foundation. I was planning on welding the beams together. I understand that bolting is the traditional way but I don't see why that would be better than simply welding the steel and then covering the metal with a protective paint to prevent rust. I know I'll need to focus more on insulation because the steel will act as a thermal bridge.
The phrasing of this question makes you sound in way over your head- please just hire an architect. AskMetafilter (or even google) is not a replacement for a licensed professional. In addition to the technical questions you are asking, you should also be aware of the zoning, permits and life safety issues surrounding the construction of a building. If you are in the US you can find one here: https://architectfinder.aia.org/frmLandingPage.aspx
posted by KMoney at 9:03 PM on December 28, 2017 [7 favorites]
posted by KMoney at 9:03 PM on December 28, 2017 [7 favorites]
The fundamental question here is: pre-engineered, or not.
If the former, then the supplier will be handling all of the connection details and, in many cases, the permits. If you don’t have a supplier, visit the Steel Framing Alliance.
If the latter, then you need to either hire an architect or a structural engineer, unless you are in an unincorporated district that doesn’t fall under a broader building code (eg: state-wide). If you are flexible on the various matters of physical design, layout, location of windows etc, then probably talk to an architect to optimize your floor plan. If you have firmly held opinions regarding where everything should go, then probably talk to a structural engineer (inasmuch as it’ll be easier than fighting with the architect, no offense to architects). Note that some states require an architect regardless (so ignore the foregoing) while other require a structural engineer regardless (so pay attention to the foregoing).
The next question is: structural steel, or light-gage. The former is what’s often (erroneously) referred to as “I-beams” (the modern designation is more detailed than that, and the most common shapes are W shapes (wide-flange). The sort of thing that holds up skyscrapers — black, large, heavy, bolted (A325 or A490, or some more esoteric types) or welded. The latter is what’s more commonly used in houses; silvery, thin, more akin to bent sheet metal, held together by self-tapping screws.
From your remark on welding, I’m assuming you’re leaning toward structural steel (note: even in a structural steel building the “infill” members can be light-gage).
In that case, bolting vs. welding is mostly a matter of efficiency: bolted connections typically require less labor, so they are cheaper but welded connections are preferred for certain circumstances (given that bolts aren’t free, there’s a trade off between cheaper labor vs. cheaper materials, for each connection). I personally can do four connections using TC bolts in the time it’d take to run one line of weld, and I suck.
If you are in a location where a building code applies, you almost certainly will not be allowed to weld the steel yourself, unless you are certified to AWS D1.1 and are prepared to lay out the connection details for each member beforehand. You’ll need a WPS/PQR for everything, and if those acronyms don’t ring a bell then you won’t be allowed to do the welds.
Personally, if this is a moment frame I’d go welded, otherwise bolted (you can have both within the same structure). If that distinction doesn’t ring a bell you need an engineer.
You might want to consider talking with a local fabricator (if you’re leaning toward structural steel); the AISC has a database of fabricators on their website — there are fabricators they don’t list, but basically all of the “good guys” will be in their database, on their website (www.aisc.org).
I could go on, but will stop here...
posted by aramaic at 9:27 PM on December 28, 2017 [11 favorites]
If the former, then the supplier will be handling all of the connection details and, in many cases, the permits. If you don’t have a supplier, visit the Steel Framing Alliance.
If the latter, then you need to either hire an architect or a structural engineer, unless you are in an unincorporated district that doesn’t fall under a broader building code (eg: state-wide). If you are flexible on the various matters of physical design, layout, location of windows etc, then probably talk to an architect to optimize your floor plan. If you have firmly held opinions regarding where everything should go, then probably talk to a structural engineer (inasmuch as it’ll be easier than fighting with the architect, no offense to architects). Note that some states require an architect regardless (so ignore the foregoing) while other require a structural engineer regardless (so pay attention to the foregoing).
The next question is: structural steel, or light-gage. The former is what’s often (erroneously) referred to as “I-beams” (the modern designation is more detailed than that, and the most common shapes are W shapes (wide-flange). The sort of thing that holds up skyscrapers — black, large, heavy, bolted (A325 or A490, or some more esoteric types) or welded. The latter is what’s more commonly used in houses; silvery, thin, more akin to bent sheet metal, held together by self-tapping screws.
From your remark on welding, I’m assuming you’re leaning toward structural steel (note: even in a structural steel building the “infill” members can be light-gage).
In that case, bolting vs. welding is mostly a matter of efficiency: bolted connections typically require less labor, so they are cheaper but welded connections are preferred for certain circumstances (given that bolts aren’t free, there’s a trade off between cheaper labor vs. cheaper materials, for each connection). I personally can do four connections using TC bolts in the time it’d take to run one line of weld, and I suck.
If you are in a location where a building code applies, you almost certainly will not be allowed to weld the steel yourself, unless you are certified to AWS D1.1 and are prepared to lay out the connection details for each member beforehand. You’ll need a WPS/PQR for everything, and if those acronyms don’t ring a bell then you won’t be allowed to do the welds.
Personally, if this is a moment frame I’d go welded, otherwise bolted (you can have both within the same structure). If that distinction doesn’t ring a bell you need an engineer.
You might want to consider talking with a local fabricator (if you’re leaning toward structural steel); the AISC has a database of fabricators on their website — there are fabricators they don’t list, but basically all of the “good guys” will be in their database, on their website (www.aisc.org).
I could go on, but will stop here...
posted by aramaic at 9:27 PM on December 28, 2017 [11 favorites]
A fundamental for me would be how close to the sea are you? In many jurisdictions anything remotely coastal has to be rust-proofed (required here in NZ - people normally use factory galvanising as paint rarely cuts it, unless applied under very tight controls). Also consider high-wind and earthquake zones and relveant rules.
Also seconding going with an engineer / architect as I would want / expect to be challenged on my material choice. And presented with a range of options that fit my budget.
Also consider helical piles (one of many systems) as they're a lot more cost-effective (time-saving) than even concrete piers - depending on site
posted by unearthed at 10:15 PM on December 28, 2017
Also seconding going with an engineer / architect as I would want / expect to be challenged on my material choice. And presented with a range of options that fit my budget.
Also consider helical piles (one of many systems) as they're a lot more cost-effective (time-saving) than even concrete piers - depending on site
posted by unearthed at 10:15 PM on December 28, 2017
Questions to consider:
The details for your piles and foundation will be worked out by structural and soil engineers. Don't set your mind on something that might not work on your lot.
What are your reasons to go for steel framing? Is it worth the extra cash to you? If you want to stay away from wood, that's cool, but why not reinforced concrete and steel studs?
How much construction experience do you have, in particular steel framed buildings (and those are typically commerical)? If you are not/don't work for a contractor, I think that you're deluding yourself in thinking you can build anything cost and time-efficiently without hiring a GC.
With the exception of attaching HSS to concrete embeds and obviously metal decks to structural members, it's mostly bolts for the structural frame. Not a whole lot of welding.
Have you pursued any sort of training on structural steel framing, sructural steel studs, and light gauge steel stud framing (those were three separate courses for me)? Once you start working on partitions, do you have powder-accentuated tools certification? It's not rocket science, but it'll take you longer and cost you much more than anyone with practical experience.
Where are you ordering your steel from? Have you talked to your fabricator? They will likely be immensely helpful.
Consider that it's much more difficult and expensive to make design changes, once your steel had been ordered, than for other types of construction. I'm yet to work on a project, commercial and residential, where everything doesn't change all the time, so you have to make sure that your frame design is final.
How much do you know about seismic bracing?
Are you anywhere near saltwater? Have you decided on what ceiling system you plan to use? Again, it can all be done, and it can be done gorgeously but $$$$.
posted by halogen at 1:36 AM on December 29, 2017 [3 favorites]
The details for your piles and foundation will be worked out by structural and soil engineers. Don't set your mind on something that might not work on your lot.
What are your reasons to go for steel framing? Is it worth the extra cash to you? If you want to stay away from wood, that's cool, but why not reinforced concrete and steel studs?
How much construction experience do you have, in particular steel framed buildings (and those are typically commerical)? If you are not/don't work for a contractor, I think that you're deluding yourself in thinking you can build anything cost and time-efficiently without hiring a GC.
With the exception of attaching HSS to concrete embeds and obviously metal decks to structural members, it's mostly bolts for the structural frame. Not a whole lot of welding.
Have you pursued any sort of training on structural steel framing, sructural steel studs, and light gauge steel stud framing (those were three separate courses for me)? Once you start working on partitions, do you have powder-accentuated tools certification? It's not rocket science, but it'll take you longer and cost you much more than anyone with practical experience.
Where are you ordering your steel from? Have you talked to your fabricator? They will likely be immensely helpful.
Consider that it's much more difficult and expensive to make design changes, once your steel had been ordered, than for other types of construction. I'm yet to work on a project, commercial and residential, where everything doesn't change all the time, so you have to make sure that your frame design is final.
How much do you know about seismic bracing?
Are you anywhere near saltwater? Have you decided on what ceiling system you plan to use? Again, it can all be done, and it can be done gorgeously but $$$$.
posted by halogen at 1:36 AM on December 29, 2017 [3 favorites]
I take back the comment about connections being mostly bolts: that's just all I've seen recently in Seattle at columns and beams. Lots of welds at other types connections, but I've studied more about them than I've actually seen in the field. It could be just the type of jobsites I've worked on.
posted by halogen at 1:49 AM on December 29, 2017
posted by halogen at 1:49 AM on December 29, 2017
Every project in my home renovation that is in any way non-standard has been a big hassle and more expensive.
posted by theora55 at 4:04 AM on December 29, 2017
posted by theora55 at 4:04 AM on December 29, 2017
Please ignore this if you have factored all this into your plans, but according to your profile you are based in Los Angeles? Because buildings in California have significant code requirements because of the risk of natural disasters. I would really suggest you talk to a licensed architect about your plans. If whatever you build isn't up to code you run the risk of having to tear down all your work.
posted by Julnyes at 7:56 AM on December 29, 2017 [2 favorites]
posted by Julnyes at 7:56 AM on December 29, 2017 [2 favorites]
So, basically, you want the Farnsworth House.
If your profile is correct and you're in California, you can't do this yourself, for multiple reasons. Almost every assumption you've made so far and listed in your question is questionable at best - the only exception is your guess about insulation (yes, you'll need that, probably in an additional wall that you build in addition to your steel frame). Just so you know where I'm coming from, I worked in residential architecture in California for a decade, and have spent the last year working in the structural engineering department of an architecture/engineering firm in Michigan - meaning I lay out and draw (not design) steel building systems and connections for a living, and I wouldn't be qualified to do what you want to do by myself.
First, although owner-builders can design and build their own houses in California, the construction of those houses is prescriptive - meaning you have to follow a very narrow set of guidelines. Any deviation from those will require hiring a professional to figure it out for you. Those guidelines limit you to a single story wood framed structure with a continuous foundation wall. For steel, you'll need a structural engineer. Part of the expense of kit homes or pre-engineered metal buildings is that you're paying for the engineer's stamp on the drawings. You just can't avoid that if you want to build something with steel. The engineer will have to design at least some of the connections between beams and columns, provide load statistics for beam end reactions, size the beams and columns themselves, detail the column connections to foundations, and detail the actual foundations. Since you're concentrating all your building weight into piers instead of a continuous foundation wall, those foundations will have to carry a lot more load than a typical section of foundation, and may require a bunch of rebar and other stuff.
Second, even if you were going with bolted connections instead of welded in general, you'd have to have some welded connections in the building to resist lateral forces (i.e. earthquakes and wind). Bolted connections aren't "traditional", they're just cheap and easy and all that's usually necessary for a gravity load. Even "bolted" connections contain welds; and "welded" connections typically contain bolts. A field-welded connection will typically require a "special inspection", meaning that you'll have to hire someone to come out an watch you make the welds and approve the job you did. They'll also make sure you have the certifications aramaic mentions. It doesn't really matter because it's not going to happen, but how did you plan on holding the beams in place while you weld them together?
I'm not sure how you got onto the idea of a steel building or how it would be a cheaper alternative anyway. If you want access to under the building, why not just build something wood framed with a crawlspace like how people have built houses for hundreds of years? You can even lift it off the ground with columns on pier footings (note - this will break the prescriptive code guidelines and you'll still need an engineer). If you're thinking it'll be fireproof, technically, yes it will be, but it'll turn to spaghetti in the heat of a wildfire (see the WTC on 9/11). At least you'll be insect-proof, but why not masonry or concrete then?
posted by LionIndex at 11:39 AM on December 29, 2017 [8 favorites]
If your profile is correct and you're in California, you can't do this yourself, for multiple reasons. Almost every assumption you've made so far and listed in your question is questionable at best - the only exception is your guess about insulation (yes, you'll need that, probably in an additional wall that you build in addition to your steel frame). Just so you know where I'm coming from, I worked in residential architecture in California for a decade, and have spent the last year working in the structural engineering department of an architecture/engineering firm in Michigan - meaning I lay out and draw (not design) steel building systems and connections for a living, and I wouldn't be qualified to do what you want to do by myself.
First, although owner-builders can design and build their own houses in California, the construction of those houses is prescriptive - meaning you have to follow a very narrow set of guidelines. Any deviation from those will require hiring a professional to figure it out for you. Those guidelines limit you to a single story wood framed structure with a continuous foundation wall. For steel, you'll need a structural engineer. Part of the expense of kit homes or pre-engineered metal buildings is that you're paying for the engineer's stamp on the drawings. You just can't avoid that if you want to build something with steel. The engineer will have to design at least some of the connections between beams and columns, provide load statistics for beam end reactions, size the beams and columns themselves, detail the column connections to foundations, and detail the actual foundations. Since you're concentrating all your building weight into piers instead of a continuous foundation wall, those foundations will have to carry a lot more load than a typical section of foundation, and may require a bunch of rebar and other stuff.
Second, even if you were going with bolted connections instead of welded in general, you'd have to have some welded connections in the building to resist lateral forces (i.e. earthquakes and wind). Bolted connections aren't "traditional", they're just cheap and easy and all that's usually necessary for a gravity load. Even "bolted" connections contain welds; and "welded" connections typically contain bolts. A field-welded connection will typically require a "special inspection", meaning that you'll have to hire someone to come out an watch you make the welds and approve the job you did. They'll also make sure you have the certifications aramaic mentions. It doesn't really matter because it's not going to happen, but how did you plan on holding the beams in place while you weld them together?
I'm not sure how you got onto the idea of a steel building or how it would be a cheaper alternative anyway. If you want access to under the building, why not just build something wood framed with a crawlspace like how people have built houses for hundreds of years? You can even lift it off the ground with columns on pier footings (note - this will break the prescriptive code guidelines and you'll still need an engineer). If you're thinking it'll be fireproof, technically, yes it will be, but it'll turn to spaghetti in the heat of a wildfire (see the WTC on 9/11). At least you'll be insect-proof, but why not masonry or concrete then?
posted by LionIndex at 11:39 AM on December 29, 2017 [8 favorites]
"what are some things I need to know/research before doing this that I may not already know?"
I realize you probably meant that question w/r/t construction materials and techniques, but don't forget banks and insurance companies. Even if you're doing all this on your own dime then at least consider the liability/casualty question. I am not an expert, just throwing it out there for you to research.
posted by forthright at 11:58 AM on December 29, 2017 [1 favorite]
I am an architect and this project is not a good idea. There's a lot of reasons why we don't build steel frame houses. It's much more expensive than wood framing. It's much worse for the environment - consider that wood is a relatively local renewable resource, whereas steel is mined and forged and then shipped long distances at greater cost than wood due to it's weight. It's harder to construct (so, more cost again). The thermal bridging is a real problem and shouldn't be underestimated. There's lots of architectural research into timber towers right now, as a way to make building more sustainable... you're proposing going the exact opposite direction.
If you do pursue this plan, you will absolutely need a licensed structural engineer and probably also an architect.
posted by annie o at 9:22 AM on January 6, 2018 [1 favorite]
If you do pursue this plan, you will absolutely need a licensed structural engineer and probably also an architect.
posted by annie o at 9:22 AM on January 6, 2018 [1 favorite]
This thread is closed to new comments.
There are a few companies that offer wood/steel hybrid buildings, where 2x lumber is used instead of steel purlins and girts, but the main structural members are still steel. This is one way to reduce thermal bridging and sources of condensation.
posted by bradf at 7:48 PM on December 28, 2017 [1 favorite]