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cuemaker
08-07-2006, 09:39 AM
Need help.

In my basement I have a laminated beam spanning 16ft with a support pole in the middle.

The beam is 4.5"x 9", roughly.

Is it possible to maybe put an I beam in its place and remove the support pole in the middle??

The beam supports the floor joists

jburstein
08-07-2006, 10:21 AM
The answer, as always, to this question is "if you have to ask, ask a professional." If you have to ask here, then you aren't qualified to do the calculations so hire a Professional Engineer who is.

-Justin, who, falling ceilings aren't funny.

winchman
08-07-2006, 10:28 AM
That sounds like three 2x10s. You might be able to add steel channels or just a flat bar to both sides prior to removing the center support, instead of replacing the wood beam with a steel I-beam. That way you avoid having to use a bunch of temporary supports.

You might want to have some way to jack the wood beam up with respect to the steel channels/bars as the support is removed to keep everything level. You'll just be transferring some of the load from the wood to the steel.

And, get some professional advice before you do anything, of course.

Roger

Evan
08-07-2006, 10:37 AM
You need to check local codes. Steel is often not permitted in that sort of application because of much reduced fire resistance. A steel beam will fail two to three times faster than a glue-lam wood beam in similar circumstances.

cuemaker
08-07-2006, 10:43 AM
Well, I understood that.

I guess my question is 2 fold.

I am sure a I beam would work, but roughly how big?

I know that I can get a w-10-22, which is 10.25 inches high by 5.75 inches wide 20ft long for $225.

cuemaker
08-07-2006, 10:45 AM
I am slow.

slightly ingnore my post except for the steel port.

Evan
08-07-2006, 10:49 AM
You will need a structural analysis. You can get close by looking up the code requirement for maximum required floor loading per sq foot and then using a program like Beamboy (http://www.geocities.com/richgetze/) to calculate the deflection of an appropriate beam with a distributed load.

LarryinLV
08-07-2006, 10:49 AM
The answer is "maybe", and you need to consult a local professional with local residential building code knowledge. 16' is not a huge span.

Not only are you asking the beam to support the mid-section with minimal deflection; you are transferring the points of support from three to only two at the outer edges. The foundation underneath may not support the load at these two points and a deeper foundation may be needed or at least additional support at the jack-studs.

A steel I-beam may work, or additional engineered beams sistered to the main may work. Doubling the size of the main support may be all you need, or a couple of additional laminated beams a few feet apart from the main.

Unrestricted pace is precious, good luck with this.

cijuanni
08-07-2006, 11:08 AM
Yes replacing the wood Glu Lam beam is possible. However, a few points.

This is a significant structural revision, a building permit would be required if you live in an area that enforces the building codes.

The Building department probally would not issue you a permit with out plans and calculation sealed from an engineer.

The steel beam needs a wood nailer bolted or shotpinned to the top flange to nail the floor joints to. Or nailing tabs welded to the steel beam.

Removing the center support dramatically increases the load to the two remaining bearing points. I assume the basement walls. Can the walls and foundation carry this additional load?

All of the above is why you need an engineer.

Mortimerex
08-07-2006, 11:16 AM
Need help.

In my basement I have a laminated beam spanning 16ft with a support pole in the middle.

The beam is 4.5"x 9", roughly.

Is it possible to maybe put an I beam in its place and remove the support pole in the middle??

The beam supports the floor joists

Yes its very possible. Impossible is the only word you will rarely ever hear a degreed engineer use although the guys with falling down pants are always telling ancedotes about the wise old guy that never went to school but showed up a young college educated engineer who claimed something was "impossible".

Anyway, I can tell you how to figure it out yourself or at least get started but won't give you the answer. After all, how many doctors will operate or lawyers sue -for free?

Basically it looks like you got a 4.5"x9" (the 9" being vertical I assume) and it has an unsupported span of 8'. Set up your beam deflection on that, noting approx 1000psi as allowable bending stress for most woods and with approx 82.7cubic inch strong axis section modulus (some extra for safety).
Now put values in the beam formula that gives deflection that is more than what you can measure on your existing wood beam.

Then set up a steel beam formula but give it an unsupported span of 16', and noting an allowable bending stress of something like 15,000-20,000psi.
Trial and error various steel beams from a handy AISC book (this is extremely tedious) until you get deflections equal or less than the existing wood beam. I would even use another set of calculations so it was done using both concentrated and distributed loads if it was something off the wall like this.

But you probably need to go to college and get a bachelor of science degree in either Mechanical Engineering or Civil Engineering to know how to do this right even though it sounds simple. You may be able to find a spreadsheet or other beam formula software written by some poor starving engineering student that will let you just randomly toss numbers and just use the standard trial&error method of nondegreed engineers.

Good luck. Just guessing, I would say a wideflange w8 steel beam might work but I wouldn't try anything smaller.

lazlo
08-07-2006, 11:31 AM
I would strongly recommend getting a PE to look at it.

If you're going to make a structural change to your home, you're going to have to file a code approval, and most counties will require certification from a PE.

If you don't get code approval, and something happens to the house, your insurance company can nulllify your policy...

This happens a lot with DIY wiring.

Mortimerex
08-07-2006, 12:34 PM
I would strongly recommend getting a PE to look at it.

If you're going to make a structural change to your home, you're going to have to file a code approval, and most counties will require certification from a PE.

If you don't get code approval, and something happens to the house, your insurance company can nulllify your policy...

This happens a lot with DIY wiring.

Yep. But, ironically if you have a degreed engineer do the calculations then it won't fall down so you won't need a code approval or a PE seal, and no one will know you modified the structure unless you tell them.

I never bothered to take the EI/PE, lot of mechanical engineers don't bother since the PE test for us is just one big messed up thermodynamics problem and most MEs don't do any thermo calcs once they're out of college.
:rofl:

Wirecutter
08-07-2006, 12:51 PM
Darn. I was going to say you should get those MIT students to make you one of those amazing trusses out of popsicle sticks - I hear they can support a truck or something. :D

Seriously though, you can ask us knucleheads for advice, which is worth what you paid for it, or you can call in a pro. The bit about voiding your insurance policy would certainly get my attention. You can find an appropriate engineering outfit in the phone book.

Speaking directly to your question, you might be able to extrapolate what you might need by checking out the plans or construction of something that looks like what you want. Usually you have to pay to look at house plans, but you may be able to wander onto a construction site. You know what to look for - a span of certain length that's designed to handle a load - like the beams you'd see looking up at the ceiling of the first floor of an unfinished two-story office building.

Failing that, I'd be inclined to overdesign the bejesus out of it. You don't want a bouncy, sagging, or collapsing floor.

-Mark

bob308
08-07-2006, 12:58 PM
you put 1/2" plates on each side of the wood beam bolted through they are called french plates. we did alot of them in houses after peopl founf out the wood beam would sag and bounce. or they wanted to take out a beam and put in a pool table.

J Tiers
08-07-2006, 01:04 PM
It sounds like your REAL issue is that you want to remove the pole...... Do you really care what the beam is made of?

Clearly there is a beam that will do what you want, maybe even without reducing your headroom too far.

But right now, nobody knows what your loading is.... what type it is, etc.

You PROBABLY have fairly even loading of some total amount, but there might be a point load that isn't very obvious. We THINK it is probably under an upper story wall, and carries some amount of floor loads plus upper story loads. But we don't know if this goes under the brick fireplace, etc, etc. The description "supports floor joists" is fine, but what do THEY support?

All we DO know is that there is a beam and a pole in the basement, and it hasn't fallen down yet. We don't even know if the pole is on a pier.

All that stuff is why you need to get an engineer in there to look at the ACTUAL installation before giving an opinion on feasibility.

I wish I had a buck for every time someone asked a question, like yours, and when the actual installation was examined, there were on-site conditions that either drastically simplified, or drastically complicated the situation.

And, yes, I certainly have heard of what BOB308 mentions..... the helper plates. Had that siggested in our house.... but that was after on-site exanmination.

cuemaker
08-07-2006, 01:42 PM
Ok, more info for you guys.

The joist doesnt not support a fire place. In the general area is a wall that divides the living room from the family room

I do have all the plans for the house.

The supports on the end. One end is the poured foundation wall. The other end I was planning to use the post thats in the middle now in addition to whats there (why waste a post?)

I have a friend who is a custom house builder. I am going to rely on him to make a suggestion as to who to talk to.


I like the idea of adding plates along side and bolting them together

Scatterplot
08-07-2006, 02:10 PM
I could do the calculations for you- it would not be hard, really any sophomore ME student probably could. The issue is not the one of the beam failing, which is the easy part, but all the other stuff, like can the walls support the new load, can the foundation support it, etc. which like they said would require an engineer.

I like the bolted plates on the side idea too.

cuemaker
08-07-2006, 03:04 PM
Steel plates that I can get.

.5" x9" x 20 feet long of A36 steel cost me $159. x 2 plus some bolts.

Rustybolt
08-07-2006, 03:31 PM
Cue. I'm pretty sure that the post is there for code reasons. I case of fire the floor wont sag.
To get rid of the post you will probobly have to go with a treated microlam beam that would be considerably bigger.

Mortimerex
08-07-2006, 04:26 PM
I dunno, the popsickle stick idea sounds like something civil engineers would do. Mechanical engineers prefer steel (maybe its a superman fetish or something). You see, when wood burns it goes poof but steel has to get real hot and even then it just sags a little (unless its a fire like the 9/11 that burns with accelerant all day without being put out). In that case the sag reaches a point then it goes "poof" too.

Now if they made steel popsickle sticks, I would have to go with that idea.

Evan
08-07-2006, 05:23 PM
A steel beam will fail long before a glu-lam beam of the same load capacity in a fire. The steel gets hot all at once and turns to taffy. The glu-lam beam forms insulating char on the outer surface and take a long time to burn through. Ordinary structural steel doesn't have to get all that hot to lose strength, at 1200 degrees it will lose over two thirds of it's strength.

J Tiers
08-07-2006, 05:36 PM
Absolutely...... Steel has to be insulated for fire resistance..... its that puffy stuff all over the beams and columns.

Years ago, McCormick Place in Chicago burned to the ground (a paint convention was there :eek: ).... I saw pictures when I visited the Forest Products Lab...

There were steel beams sagged into half circles, and charred wood beams right next to them still bridging across space holding some load...

Wood just does not burn well in the form of a big beam or log. That should be intuitively obvious to the most casual fireplace fire-lighter....

Mortimerex
08-07-2006, 06:23 PM
I was comparing steel to plain wood lumber used in most residential homes. Also fires are chaotic things it is possible for all sorts of odd things like an unmelted styrofoam cup in the same room as puttyified steel. I think if you do an actual scientific analysis with identical heat sources applied to wood and steel beams alot of ancedotal "evidence" will disappear.

garyphansen
08-07-2006, 08:10 PM
Evan is right, of course! A Wood beam is much more fire resisent than a steel beam in a house fire. I design houses for a living, and I never use steel beams for the following reasons, Less fire resisent than wood, Cost more than wood, Weight more than wood (meaning you need a crain on site to install them), and as someone pointed out you need to drill the top flange to attach a 2"x to nail the floor joist to. Also, cutting them on site is a problem.

To figure out what size beam would be needed to beable to remove the center post you would need to know such things as the span of floor joist that rest on the beam, does the beam carry any wall weight? Does it carry weight from more than one floor or any roof load? Is there a post above the post in the basement that carries anything weight? Are the post pads for the posts on both sides of the center post large enough to carry the addition weight.

I would not size a beam for an existing building with out inspecting the building because when I have talked to builders over the phone I have discovered they have not properly discribed everything that is going on with the loads. Gary P. Hansen

Evan
08-07-2006, 08:18 PM
It isn't anecdotal evidence. A lot of building codes require glue laminated roof trusses in places like theatres because of the proven fire resistance compared to steel.



http://vts.bc.ca/pics/glamtxt.gif

http://www.branz.co.nz/branzltd/pdfs/OwenGriffiths.pdf

Mortimerex
08-07-2006, 08:26 PM
It isn't anecdotal evidence. A lot of building codes require glue laminated roof trusses in places like theatres because of the proven fire resistance compared to steel.


Sorry buckwheat, that is not plain lumber its glue laminated. Get your facts straight. I bet you could laminate steel with something to give similar results.

Evan
08-07-2006, 08:30 PM
I have no idea what you are talking about. I am talking about glue laminated beams. Cuemaker is talking about glue laminated beams. The test I quoted is talking about glue laminated beams. What are you talking about?

wierdscience
08-07-2006, 08:40 PM
Evan is right and wood is wood no matter how it is glued.

We used to use Fletch beams all the time in home construction.It's basicly three pieces of 2x demensional lumber with two pieces of steel flatbar slipped in between the two outer 2x's and the whole mess is through bolted with some grade 5,1/2" bolts.

This type has several adavantages,it can be assembled in place one piece at a time with two guys on ladders.It has built in nailers,and because it is wrapped in wood it meets fire codes.

The typical places we used it were over three+ car garage doors and under second floor jacuzzi's.We had one that supported a 600gallon whirpool bath in the middle of a 18' span.Three 2x12"x18' and two 3/8"x12 flatbars 18' long and 32 1/2" bolts.When it was done the bath was filled and the beam didn't deflect even a 16th.

lazlo
08-07-2006, 09:44 PM
I have no doubt that timber or glulam is an acceptable building material, but the study that Evan posted is rather dubious, since it is written by "McIntosh Timber Laminates, LTD.", in an attempt to get "the Asian regulatory bodies" to lift a ban on glulam construction.

Somewhat like Exxon writing a global warming paper.

The test they ran measured the core temperature of steel, concrete, and glulam beams inside a furnance, which is strange, since the standard US, Canadian, and EU fire safety test is a char test where they quantify the amount of material removed by the fire per unit time (i.e., millimeters per minute).

So in MTL's test, with steel being a great conductor, the core temperature goes up about as fast as the furnace temperature. No surprise. Wood being an excellent insulator, the core temperature goes up slowly. No surprise, but that has little bearing on how much wood is being removed by the fire itself.

The really amusing part of their study is that if you look at the furnance temperature for the glulam, it spikes up 350 Centigrade after 2 1/2 minutes. This is explosive combustion from the glulam beam itself :)

With all the fuel from the glulam, the furnace chamber temperature ends up at 800 Centigrade, while the steel and concrete beam the furnace ends at 300 - 400 Centigrade.

In a couple of more objective US Forest Service and USDA reports, they indicate that common 11-laminate 5 x 16 1/2" Douglas Fir glulam beams do not pass the standard 1-hour or 2-hour ASTM fire exposure test required for public buildings. On average the glulam beams failed after 35 - 40 minutes or so. So their recommendation was additional layers of laminate to increase the overall width and depth to account for material loss due to charing, and bring the beams up to code.

http://www.fpl.fs.fed.us/documnts/fplrp/fplrp467.pdf
http://www.fpl.fs.fed.us/documnts/fplrp/fplrp460.pdf
http://www.fas.usda.gov/gainfiles/200512/146131654.pdf
http://www.aewc.umaine.edu/conference/ABSTRACT%20pdfs/Williamson.pdf

Evan
08-07-2006, 10:10 PM
Glulam still beats steel by a wide margin. The only way for steel to equal the performance of glulam is to cover it with insulation. If you then do the same with glulam then it still beats the insulated steel.

rantbot
08-07-2006, 11:16 PM
I dunno, the popsickle stick idea sounds like something civil engineers would do. Mechanical engineers prefer steel (maybe its a superman fetish or something).

Popsicle sticks? A shameless luxury. When I was a poor deprived ME student we had to make our beams out of drinking straws.

Civ E's didn't build structures. They just brought in rock samples to crush in our Instrons and got chips everywhere.

ASparky
08-07-2006, 11:52 PM
Waxed paper straws too not plastic. Oops that is giving away how old some of us are. :)

dicks42000
08-08-2006, 01:23 AM
Somebody mention testing machines. Instron & Tinius-Olsen. Are these still being made in US? Brings back fond memories of 2nd year matl. science labs.
Rick

Mortimerex
08-08-2006, 02:04 AM
I have no idea what you are talking about. I am talking about glue laminated beams. Cuemaker is talking about glue laminated beams. The test I quoted is talking about glue laminated beams. What are you talking about?

Just a plain wood beam is not laminated with anything that I've ever heard of.
There are polymers uses in fire resistant coatings that when they burn actually absorb heat as well as put out the fire, so comparing bare steel to a gluey thing isnt straight up. Also according to AISC structural steel has 100% strength at up to 700 degree F or about 370 degree C. Which means their claim is just plain Bullcrap.

Alguy
08-08-2006, 02:33 AM
I have a 16 foot laminated beam in my garage to support the roof on the eve side it is 4" by 14" by 16 foot , it is what i had to use to for local code, the building inspector said i could not use 2 X 12 , it does make it very rigid, i did get a cerificate with it and stated it could carry a 7800 lb load ( if my memory is right)it was basically pressed and glued 2x4 , when i drove in the 16 penny nails they drove very hard this was very densely pressed piece of wood . My point is that to support a 16 foot span it is going to be pretty tall beam to carry much of a load. my beam was only to support the roof over a 16 foor garge door. my 2 cents allen

gmatov
08-08-2006, 03:17 AM
This will convince nobody of anything, but, when my youngest was building her house, I argued with the builder to put in an 8 inch wide flange steel beam, no posts. They said they would, for an additional 2200 bucks. It would be 22 feet long.

As is, they have a 4 1/2 X 9 1/4 (nominal 2 X 10 tripled ) and 2 support columns.

In this case, they admitted the beam would do the same, but you gots to pay for it.

If the perch in your foundation wall will not take the load of the beam, you should sue the contractor and the PE or CE who approved the plan.

To go back a few pages, I have never in 40 years or so known a builder to drill for bolting the sill plate to the beam. A few WILL shoot a few powder actuated fasteners into it to make it stay in place, but most of them will just anchor it with toenails through the joists.

Of the advantages of the steel beam, other than unsupported span, is the reduced shrinkage. You have a plate on the steel, which will shrink and expand right along with the mudplate on the foundation walls. The house will settle and rise at the same rate.

You have 10 inches on top of posts, it will shrink and swell correspondingly more, 6.66 times more with a 10 inch wood beam and 1 1/12 inch sill plate. Center support wall will sag, plaster will crack, stuff will tend to drift to the center of the house.

Glued up laminates, not what you are speaking of, but what Evan is speaking of, are actually very thick plywood. Mebbe a third of it is the adhesive. Have NO bearing on a built up, triple 2X beam.. Have an aqaintance whos son is in that business in Nevada, I think, builds them to 70 feet or more, thin veneers, much glue, either urea-formaldehyde or epoxies, any shape you want, as per all the wierd churches you see today.

THESE, if you go to one of those churches, you will see, are laminated crossways, not like traditional plywood. ALL follow the curve, not like a piece of ply you saw a piece out of. This wood has no strength at all in the flat, it is strictly the glue bond to the wood that allows it to support the roof of a church. The wood used is important, too, as, if it tears apart from the glue under stress, the wood failing, there goes another lawsuit.

My own 24 foot wide garage is sagging in the triple 2 X 12 beam, single post. Floor is settling, foundation was backfilled, apparently not compacted enough.

Next idea is to suspend it with 3/8 cable from the ridge board, get rid of the post entirely. Clear it out, a helluva job, pour a new floor.

Cheers,

George

J Tiers
08-08-2006, 07:50 AM
Just a plain wood beam is not laminated with anything that I've ever heard of.
There are polymers uses in fire resistant coatings that when they burn actually absorb heat as well as put out the fire, so comparing bare steel to a gluey thing isnt straight up. Also according to AISC structural steel has 100% strength at up to 700 degree F or about 370 degree C. Which means their claim is just plain Bullcrap.

Not So.... :rolleyes: As is immediately obvious to anyone who has tried to start a fire with logs, a thick piece of wood just does not want to burn.

The wood has considerable insulating value. Steel has none.

The wood is not a very good heat conductor, so the inside of the wood is not hot when the outside is burnt.. Section a piece of burnt wood if you think that is bullcrap.

Steel is a very decent heat conductor by comparison...

While the wood is burning, it is giving off vapors and fumes.... which is most of what burns other than "coals".... those vapors and fumes absorb heat and carry it off as they are evaporated or "cooked out".

Steel sits there and heats up, conducting heat to areas not quite as well exposed to the fire, to make sure it getrs nice and hot.

Even if you just think about it, you can easily see that the wood can stand up longer in general.

Then of course there are the observations, which have been here dismissed as "anecdotal".... and therefore false and misleading :rolleyes: . They support what would logically be expected.

Apparently this, in your world, proves their falsity.....

bob308
08-08-2006, 08:38 AM
just think for a little if the house bruns enough for either beam to fail what does it matter???? all you have any way is a pile of ash.

Millman
08-08-2006, 08:44 AM
Good point, Bob; common sense replies are always justified

Evan
08-08-2006, 09:15 AM
It makes no difference as long as the ashes are not yours. Fire resistance ratings are all about escaping.

J Tiers
08-08-2006, 12:30 PM
It makes no difference as long as the ashes are not yours. Fire resistance ratings are all about escaping.



As is "earthquake resistance" construction...... as well as things like firestops in the walls, which way doors open, etc, etc.

cijuanni
08-08-2006, 12:39 PM
If the perch in your foundation wall will not take the load of the beam, you should sue the contractor and the PE or CE who approved the plan.


Why would the contractor of engineer be liable for an inadequate design of a "perch" that never considered using a single span beam in the original design??

At least one of those supports will be subject to a 100% increase in service loads from removing the post.

Millman
08-08-2006, 03:37 PM
Evan; did anybody ever tell you, that if you were that smart;; you would never waste your time communicating with people under your level of INTERNET intelligence? Hell, if I were as SMART as you, I would be posting on another site as the ENGINEER that you claim to be. Face it man, you are stating the only facts that any imbecile can Google for canned info....I grew up with 3 teachers, and one thing they taught me ,,,,have respect for your fellow man. You do not have that ability. Some people have to be the Center of attention... and this forum ,,,for YOU,, is it. You are not always correct, You are a Talking textbook. Then again...any textbook is only filled with the author's OPINIONS, and you indeed have hundreds of followers...Do you have any personal opions about metalworking? Reading you is like a primer. Surprised noone has ever taken you to task for what you have printed. But then again; some people just HAVE to be respected in print; even though they do not have the Practical experience. What say you, in order of defense????

garyphansen
08-08-2006, 04:33 PM
Millman: You sond like a five year old kid telling his CPA dad how to do his Income tax! Gary P. Hansen

speedy
08-08-2006, 06:18 PM
It makes no difference as long as the ashes are not yours. Fire resistance ratings are all about escaping.

If we are concerned with incineration here ( the dwelling or personnel ), then fire alarms and sprinkler systems are equally important considerations .
Personally, I agree with Bobs` statement.

Evan
08-08-2006, 06:49 PM
Here is some info from NIST

http://vts.bc.ca/pics/steelstrength.gif

Steel doesn't do well at all at the temperature of a burning building. Glulam isn't fire resistant because of the glue. Phenol resourcinol glue is used, same as plywood. It is also flammable and there isn't much glue in the beam anyway. Glulam is strong because of the averaging of the wood properties produced by laminating and fire resistant because of the way wood burns in large sections.

lazlo
08-08-2006, 08:30 PM
Glulam still beats steel by a wide margin. The only way for steel to equal the performance of glulam is to cover it with insulation. If you then do the same with glulam then it still beats the insulated steel.

Not really. An exposed steel beam passes the 1-hour ASTM burn test with just a thin layer of cheap gypsum/vermiculite foam. With the fancy new thin film intumescent coatings, exposed steel beams can pass the 2-hour test. More importantly, steel beams are rarely exposed -- they're almost always protected behind gypsum board or plywood firewalls. Glulam "suffers" from the fact that it's used primarly exposed because it looks nice as an architectural element.

As the USDA publications I linked indicate, standard 11-layer glulam only lasts 35-40 minutes without additional protection (either the same gypsum/vermiculite foam, which defeats the purpose of an exposed beam, or additional lamination layers).


Here is some info from NIST

Right, that data confirms the information Mortimerex posted earlier -- that steel maintains its structural integrity up to 750-800F:


Also according to AISC structural steel has 100% strength at up to 700 degree F or about 370 degree C.

In any event, none of this discussion is of any consequence to cuemaker's original question.

cuemaker
08-08-2006, 08:37 PM
In any event, none of this discussion is of any consequence to cuemaker's original question.


LOL. But I have read ALMOST everyword, really.

lazlo
08-08-2006, 08:43 PM
LOL. But I have read ALMOST everyword, really.

I think you suggested the best answer in the whole thread Cuemaker: you said you have a friend who is a builder -- I'm sure he can point you to the right people to help you...

LarryinLV
08-08-2006, 08:45 PM
It seems clear now. (warning, parts of this post may be tongue-in-cheek, read at your own risk)

My gun safe should have been made of wood. After my house burns to the ground I guess there will only be a little puddle of guns and safe in the dirt. If it had been made of lumber then I would still have an only slightly charred box and all would be well.

Anything over a few stories is going to be spec'd for steel 'cause sticks won't support the load without clearing the forest for sufficient load bearing walls.

An I beam of sufficient size in the basement is going to support the load where the present glu-lam won't. The wood is going to burn at 450 degrees, the glue even less. The I-beam will probably never be subjected to a high enough temperature long enough to fail before the house burns to the ground around it.

The only real issue for the home owner here is will the foundation or outer walls support the load of the floor without help.

edited: note that this is moving so fast some information is covered while just composing a readable post.

Evan
08-08-2006, 09:28 PM
The I-beam will probably never be subjected to a high enough temperature long enough to fail before the house burns to the ground around it.

That is academic if the code won't allow it, which is what I said in my first post about it.

speedsport
08-08-2006, 09:47 PM
I made my living doing tenant buildouts in shopping malls, where all structual wood had to be non combustible certified, anybody want to toss this into the discussion?

wierdscience
08-08-2006, 09:58 PM
The real underlying problem here is,how much head room is there to play with and is there enough room to snake a 16' long anything into the,basement,crawl space what have you?

You may have few options and depending on the load the current situation is supporting a steel beam may not be able to carry the load without deflecting if your stuck with the original vertical dimension.That's why I suggested the Fletch beam as they can be built up to whatever capacity is needed in the same vertical space.

It's also a lot easier to pack a few 2x's and some flatbar than it is a 350lb beam:D

LarryinLV
08-08-2006, 11:13 PM
Building codes are occasionally knee jerk reactions to perceived problems or local condition or politically driven and are not always based in sound science or engineering practice.

Chicage still requires all electric to be run in conduit because a fire was started by faulty electrics. San Fran requires a whole host of requirements for gas lines IIRC. Florida requires hurricane anchoring in random areas. But they all can be granted a variance and frequently are.

Except in timber country, I would be very surprised if a local building code specified wood only and would not allow a variance on a properly engineered I-beam support in residential construction.

Despite all the rhetoric in this thread, a steel I-beam in the OP's situation is a viable option to explore.

Especially if he needs the floor space for a new lathe or mill.

Evan
08-09-2006, 01:37 AM
Here is an interesting link with some ideas.

http://www.constructioncalc.com/PDF/Gad_Theres_a_Beam_Sprouting_From_My_Countertop.pdf

Millman
08-09-2006, 01:50 AM
Just scanned that and that guy actually uses his common sense talents.