Looking to Use Steel Beam in Residential application

[Apexpredetor]

Morning All,

I am looking to use a steel beam in a residential application. Trying to open up basement, but I am not too familiar with construction techniques to be able to specify the connections. ANy good references that might point me in the right direction?

I am a NY PE, not a home owner. I can probably brute force method design a beam, column, and footers, but any quick tips or references will be much appreciated.

 

[fegenbush]

The beam and column design should be to the AISC Steel Construction Manual (14th Edition is current, previous may be acceptable). This reference covers connections to other steel members as well.

The footer sizing will be controlled by the soil conditions. Design of concrete items will be dictated by ACI 318 (2011 Edition is current, previous may be acceptable).

I highly recommend seeking the services of a competent structural engineer in your area. If you are able to do some of the work yourself (drawing preparation, e.g.) the cost should be quite reasonable.

Also remember that residential contractors are allergic to steel.

 

[Apexpredetor]

Yes, residential contractors hat the steel I-beam idea.

I am competent in the design of the beam and column, but the connections allude me. Never asked to do steel in residential construction.

 

[JAE]

Apexpredetor - you've posted here several times asking for "quick tips" to design basic structures for others (apparently).

If you don't know how to competently design something as basic as a steel beam in a residence, then the best thing would be to hire a structural engineer or take classes in this subject.
Teaching basic engineering principles isn't the focus of this website.

 

[msquared48]

Steel and wood framed residences generally do not mix we3ll, with cracking and differential settlement occurring over time.

More critical in green rather than seasoned lumber though.

The connections used de3pend on the situation you have. As JAE said, have a local structural take a look at your situation and give you come recommendations. Book pictures will not work in all cases.

Mike McCann
MMC Engineering

 

[Apexpredetor]

Not quick tips. I am trying to move away from brute force method of designing from scratch, and try to use more prescriptive methods if available.

Yes, I am a younger engineer with my PE. I am asked all of the time to do small project for people that I typically turn down, but that does not mean that I am not interested in how they are accomplished? I am sorry if you see my inquiries here as a means to a quick answer! That is not the case. We all progress as engineers by continued education, right? IF not self learning on topics you are interested in, how else do we learn. Did our engineering degrees not teach us how to learn on our own, or to be able to think critically? Because I don't do structural design 40hrs a week does not mean that I am not interested in the topic!

I try to form my questions so I don't get the standard "hire an engineer" answer. I am an engineer with a good understanding of the basics just looking for a point in the right direction to satisfy my curiosities. I have never once asked a question in the form of "...I have an XX length beam, XX width house, xx snow load, xx length opening, please tell me the answer..."

I am by no means an expert, and I am designing a structure for MY OWN RESIDENCE (garage attached possible basement under, floor above dreams ha ha) in my spare time.

I don't mean to offend or be nasty, but I'm not looking for somebody to give me any answers, just ideas, and direction.

 

[racookpe1978]

"Connections" ?

You've got a couple of problems - and, I'm not sure exactly where you are looking for help. What we did a few years ago was the following: Resedintial house, basement was about 25 feet across with 2x 3" pipe columns that the contractor wanted to open up into a single room. Apparently, similar to your situation. One wall of the basement was open to access from the side.

We cut a hole in that wall high enough and large enough to slide the beam directly in from the outside - don't have sizes, but I believe it was a W12 or W10 x ???, standard A36 grade. Obviously, YOU have to size it based on span and loads. We cut the beam to length outside the house (no flame-burning and clear grinding inside!). The existing pipe columns were left in place until the beam was slid into the basement, lifted up manually into final position, and on its final supports. We needed 6x people to lift, assume each can only lift 150 lbs over their head if on good supports or scaffolding. Otherwise, plan on several jacks underneath - obviously, you can't use any crane through the roof. The contractor did not want anything settleing, so he jacked up the old floor with temporary verticals very very slightly to get the load off of the old columns and to allow the new beam to move into place just slightly "above" its final elevation.

Once up against the floor joists, we supported the W10 beam at each end with 2x vertical columns that were end turn bolted against the existing basement walls (either brick or CME - I do not remember - and to their own floorplates on the old concrete. Once the new beam was in place and jacked up firmly against the old joists, (since the old joists were actually lifted a little bit ("un-sagged" may be a better word)), the 2x pipe columns were felt to be "loose" and could be simply pulled out since the temporary verticals were carrying the load of the floor above. With the new beam in place and secure at both ends, the temporary jacks were relaxed that little bit they had lifted the floor (1/16" perhaps) so the old joists were lowered and transferred their weight to the new beam.

We had two or three old joists that needed to be smoothed (sanded off) so they touched the new beam evenly with the rest: This is because the new beam was "perfectly flat and dead level" on top and the old wood was "not so perfectly flat" and "not so perfectly level" across its average bottom with these few being too low or slightly twisted by the old nails. 8<) The hand grinder we used to smooth the W10 beam was more than adequate to trim the 2x12 where required in only a few seconds. Old joists that were too high to touch the new beam were shimmed with wood shims firmly wedged in place.

I do not remember how the new columns were attached to the new beam. We are in a no-seismic zone. Anything that works in your case will be adequate.

The new end columns were covered by 2x4's and sheetrock panels to match the rest of the new basement's interior walls.

Remember to plan the holes in the basement walls for lifting the new beam up and sliding it in safely, and remember to get enough people in the right places to do that lifting safely.

if you can't get sideways access into the basement, I'm not sure how you can get the new beam into position. I most definitely don't recommend cutting it and re-splicing it by welding inside the basement unless you have a very, very skilled welder who can work in remote sites safely.

 

[Apexpredetor]

IT would actually be a new build with crane/telehandler access. We can pour footing as necessary, and design wall supports as necessary. We did something similar to what you described when I was a kid to an old home the family owned. Huge pain. Lots of people to lift, and tight spaces due to temp supports of joists, ect...

Thanks for the ideas and help. Appreciate it

 

[CELinOttawa]

Steel and Timber mixed is the standard form of construction in most serious cold weather climats, or at least was until the introduction of LVL and other "engineering" timbers.

You need a Structural Engineer's help. The added efficiency is going to pay for their modest fees. We are one of the cheapest of all Engineers. What's your time (and the risk of screwing up) worth to you?

 

[TenPenny]

Here in New Brunswick, Canada, almost every residential garage has a steel beam carrying the floor above, and probably 50% of the houses use steel beams in the basement, so all of our residential contractors are quite familiar with steel, they're not allergic at all.

 

[CANPRO]

Apex, the connection depends on if you want the beam within the depth of the floor joists or not.

If you drop the beam below the joist: Typically a timber sill is bolted to the top flange of the beam and then the joist are toenailed into the top of the sill.

If you don't want a dropped beam: In my area two options are typically used...either pack the web of the beam with timber and thru-bolt the timber, then use face mount hangers for the joist. Or bolt a sill to the top of the beam and use top-mounted hangers for the joists.

Your connections will affect the beam design because that is where you're getting the support for the compression flange. For the flush beam option, Mike raises a good point...the joist will shrink and the steel will not, so make sure you leave the joists up higher than the steel or you'll be sanding down the hump in your floor when the wood shrinks.

 

[Apexpredetor]

CEL.. I'm in NY and I don't see many residential with Steel beams with the introduction of the LVL.

I appreciate the concern for hiring an engineer, but this is my own structure, and it won't be built for another year (most likely two), so I would like to gain as much knowledge and information about my intended materials before I actually go out to another engineer. In all likelihood I will use LVL, and wood I joists for my members. Being asked if I had ever considered a steel beam by a co-worker made me consider it.

Basically I am going to design the beam and footers using poured wall (or filled CMU's) at beam bearing on foundation walls.

I was most concerned about the length of members (thinking 40ft is max length, but weight will be killer at that length) and how to tie them together longitudinally if needed. Guess it comes down to a bearing plate strength issue at member joints since the joists provide the lateral support. Not sure if I will flush mount the joists on hangers or 2X on top of flange to provide nailing surface for joists.

I have pretty good soils, but I will go on the low end and assume 1500psf (clay) to be conservative with footer design. I don't mind using a little more material on my own house, especially in the foundation elements.

So I have taken care of the end bearing, footers, and beam sizing. I am still left with connections. I always hated detailing ha ha.

 

[Apexpredetor]

CANPRO. Didn't think about the shrinkage of the joist. Good call.

Hmmmm, what would be a decent offset? 1/8"? I have never thought of the amount the joist wil actually shrink.

 

[CELinOttawa]

The most reliable detail for using steel is to sit a level field of timber joists on the bolted sill CANPRO mentioned, then carry the steel to foundations on jack-posts (adjustable telescoping steel columns). In this way you get a solution where the tendancy of the timber to shrink is irrelevant and the steel is not supported by timber (have seen some nasty results of that).

If you actually intend to use another engineer, just do your work by rules of thumb (like SPAN/20 to SPAN/25 for the size of your steel beam). If you are keen to do your own design, I'm sure people here would be happy to keep helping you...

 

[Apexpredetor]

I will most likely be doing my own design because I really don't think that the steel will provide much in advantage and I will probably go with LVL and I joists, but I am now curious to the applications and designs of this scenario with steel beam.

I'm stumped on how to connect the beams longitudinally if the beams are not continuous members.

 

[AELLC]

This isn't really related to the OP but we frequently use steel beams when the second floor of a house is over a large clearspan garage and the front elevation of the second story is set back from the front of the garage, and those pesky conditions where a beam bears on the exterior wall, and the roof slope necessitates the top of the beam to taper down to practically nothing to match the roof sheathing. Those frequently don't work as LVL or glulam.

 

[CANPRO]

I would use min. 1/4", but as CEL mentioned your best bet is to rest the joist on top of the steel (if you can live with the bulkhead) so that this is not an issue.

"I'm stumped on how to connect the beams longitudinally if the beams are not continuous members." <----- not sure I get your question. If the beam is designed as a single span member then you don't have to connect them longitudinally.

 

[structSU10]

As a caution, garage over a basement can be tricky, especially in CNY. In the past 2 months my firm has seen garage floor collapses due to deterioration of the slab from the deicing salts the car drags in. The reduced service life of the floor, and the expense of maintainence and repair, are something that would be better to avoid by just having it be a slab on grade.

There are publications on wood design that are free downloads (can't remember exact names) that discuss shrinkage potentials in dimensional lumber. I would think that installing a 2x nailer to the beam, along with using wood joists, you may not have any noticable differential shrinkage, but I could be wrong.

Getting an AISC code book would be a good place to start to get an idea on the connection types in steel.

 

[AELLC]

""I'm stumped on how to connect the beams longitudinally if the beams are not continuous members." <----- not sure I get your question. If the beam is designed as a single span member then you don't have to connect them longitudinally"



Isn't that simply 2 beams on rectangular column cap plate, and 2 bolts to each beam's bott flange (4 total)?

 

[Apexpredetor]

When I say connecting them longitudinally I am referring to a long narrow type structure of greater than 40ft. I am thinking my structure will be approx 28ft x 48ft. I am thinking that I am not going to get a beam over 40ft in length (or get one shipped very cost effective) so I would have two beams each 24ft (not including the bearing on concrete length). Each end bearing on concrete foundation wall, but in the middle would be a discontinuity/break. This would not be a continuous beam member. I hope I explained this in enough detail.

SU10

I was thinking about the hollow core clear span modules for the floor over basement in the garage area. capped with HDPE, and 2-3" grout. Seems to protect the floors well if done correctly.

What was the construction type used in the garage floor failure you worked on? I am also in Upstate NY area.

Thanks again all.