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[xAm]

OK, get yer' mind outta' da' gutter kids... I'm talking footings for a slab here!!

If my walls are 2x6 w/3/4 MDF and 2 layers of 5/8 Gypsum, how thick and wide should the cheeks be if I want to allow for the added weight of a brick or stone veneer?

Everything I've calculated so far, indicates that it should be 12" wide and 8" thick for the wall, LESS the potential stone or brick veneer.

Thanx,
Max

[franman]

Max,

Not my area of expertise (Structural engineering) so I'm gonna watch from the sidelines on this one... we would hire a structural engineer for any bldg shell foundation or footing work.

[Mark Pixley]

Strip footings?

A little more info would be helpful.

Most calculations need soil elasticity etc...

But if you're doing a typical turn down footing there are a few simple rules.

Probably would help to know what the stone veneer might weigh, thickness etc... and cement psi you are planning on using.

[xAm]

Pix wrote on Sun, 29 October 2006 01:13

Strip footings?

Yup, just a regular footing for the slab(b) of the rooms. Slabs will probably be typical 4" w/steel rebar grid.

Quote:

A little more info would be helpful. Most calculations need soil elasticity etc... But if you're doing a typical turn down footing there are a few simple rules.

Essentially, I thought there should be a couple of rules to go by.

Quote:

Probably would help to know what the stone veneer might weigh, thickness etc... and cement psi you are planning on using.

It's been awhile since I've done a LOT of concrete work and any update in my education you can offer are GREATLY appreciated.

OK, from what I know, I'll need to use at least a 550 PSI concrete, correct?

Again, a standard 4" slab for each room w/rebar grid. Slab has been recommended to be set on a 4" compacted sand bed. (Including the cheeks)

Since I have not entirely made up my mind as to which walls will need to be either a stone or brick veneer, I would like to keep my options as open as practical... the operative word here is PRACTICAL. e.g. I would rather incur the expense of over engineering the cheeks, rather than under engineering them and end up with problems down the road.

As far as the weight of the veneer, I'm probably going to use a standard size/weight brick. The option of a stone veneer would probably have to be limited to a type of stone that will be an equivalent weight of brick... if there is such an animal.

[Mark Pixley]

16" deep typical. But that is normally determined by the local frost line (Its 18" where I live @ 7200 ft above sea level).

Add your brick ledge and your good to go.

Typically slabs are 2500-3000 psi these days.

Don't forget to check if your area requires soil poisoning (termite control) under the slab.

(The local batch plant (cement company) is probably the easiest place to find out, just give 'em a call and ask what is typical for your region and they will gladly tell ya.)

[xAm]

Pix wrote on Sun, 29 October 2006 10:13

16" deep typical. But that is normally determined by the local frost line (Its 18" where I live @ 7200 ft above sea level). Add your brick ledge and your good to go. Typically slabs are 2500-3000 psi these days.

Pix,

THANX!!! At a couple o' hundred feet, I'm pretty sure that the frost line is going to be 16"...

So, in your opinion the the width of the cheek should be the thickness of the wall (6+.75+1.25+3)*2 = 22"x16"@2500-3000 psi?

That 2500-3000 psi... is that at 30, 60 or 90?

Which brings up another question. Who is responsible for the cure tests/reporting? Are they done by the concrete contractor, the GC or the concrete vendor?

(I'm debating whether to take on the GC role)

Quote:

Don't forget to check if your area requires soil poisoning (termite control) under the slab. (The local batch plant (cement company) is probably the easiest place to find out, just give 'em a call and ask what is typical for your region and they will gladly tell ya.)

I'll definitely check on it... seems like it would be a pretty good investment to look into even if they don't require it! Then again, sometimes... a mind is a terrible thing, ya know?!?!

Thanx again!!!

Max

[franman]

Guys,

Look we do a lot of work with COncrete... floating slabs, jack up floors, etc.. and I have a reasonable understanding of how it works. We always use at least 3000psi concrete. on floating floors (jack up type especially) we use 4500psi "High Early" which uses a different mix to cure to 3000psi within 10 days..

What I'm getting at, is that any project that involves pouring a concrete slab and footings should at least involve the consultation of a professional engineer... structural, civil whichever is correct for your project...

I STRONGLY suggest that you make contact with a local engineer... as a matter of fact any local concrete contractor who is reputable shouldn't even pour the stuff without a plan from a qualified engineer IMHO..

Look, I know this is a "do it yourself" forum, but I hate to see folks discussing expensive, and impossible to fix, structural issues without consulting with a professional engineer.. Okay, I'm down off my soapbox now.. good luck!!

[xAm]

franman wrote on Sun, 29 October 2006 18:54

Guys, Look we do a lot of work with Concrete... floating slabs, jack up floors, etc.. and I have a reasonable understanding of how it works. We always use at least 3000psi concrete. on floating floors (jack up type especially) we use 4500psi "High Early" which uses a different mix to cure to 3000psi within 10 days.. What I'm getting at, is that any project that involves pouring a concrete slab and footings should at least involve the consultation of a professional engineer... structural, civil whichever is correct for your project... I STRONGLY suggest that you make contact with a local engineer... as a matter of fact any local concrete contractor who is reputable shouldn't even pour the stuff without a plan from a qualified engineer IMHO.. Look, I know this is a "do it yourself" forum, but I hate to see folks discussing expensive, and impossible to fix, structural issues without consulting with a professional engineer.. Okay, I'm down off my soapbox now.. good luck!!

Francis,

STAY ON THE SOAPBOX!!!

I guess I didn't really present this in the most accurate of light... my apologies!!

As my budget's pretty thin, I'm being forced to try to get my drawings and spec's as close as I possibly can, so when I take them to a structural engineer for approval, that I spend my money and the engineer's time wisely. I'm sure I'm going to have plenty of markups to fix as it is, but if I can at least get the majority of the drawings and spec's right the first time through, the engineer should be better enabled to pay attention to the details, as opposed to the stuff that should have been the more obvious.

Like you, I DO NOT condone doing ANYTHING like this w/o at least a structural engineer's approval!!! (Legally, I don't think you can in most states.) I know that here in NC, you can't build any structure that requires a certificate of occupancy without an engineer's seal.

I guess I should also include the obvious caveat... no one should EVER try to do any type of construction/renovation of any type w/o the proper permits and inspections either!

You not only save your butt from fines, but should anything ever go wrong... your insurance company(s) can (and usually do) deny ANY kind of claim unless ALL the proper permits and inspections were done.

Max

[franman]

Understood.

To be honest Max, the stuff you're looking for is "standard details" that any structural engineer who does buildings in your area will just spit out from his CAD library regardless of what you've drawn in advance... Hope I don't sound tooooo jaded, but I've seen it soooo many times..

Sometimes I think we think more about this stuff, than the engineer's do, but we have to use them, because structural engineering is actually NOT very intuitive. Everytime I think I've come up with a good solution for a structural dilemma, I'm usuall shot down with some "real" engineering that contradicts what I thought was going to work??? go figure??

Anyway, I don't want to discourage you from going in prepared. This is a good thing. Just don't be surprised if the engineer says give XXXX (dollars) and I'll give you the drawings you need to file and do this legally, and XXXX will have nothing to do with how much homework you've done.... of course, you might actually find a reputable engineer who cares about his cients, and does individual work for each job...... naaaah... that thick never works!!!

[xAm]

franman wrote on Sun, 29 October 2006 19:23

Understood. To be honest Max, the stuff you're looking for is "standard details" that any structural engineer who does buildings in your area will just spit out from his CAD library regardless of what you've drawn in advance... Hope I don't sound tooooo jaded, but I've seen it soooo many times..

Francis,

Jaded is both understandable and actually appreciated! I've found that I'm pretty jaded myself about a lot of things. It's always based upon experience and honesty, right?

I'd rather know the bitter truth and save myself a great deal of embarrasment and frustration. So, I pay a little more to get the drawings right... better for em' to be right... the first time. It saves money in the long run.

So, another STUPID question...

What type of engineer should I be seeking out? Architectural Engineer, Structural (Commercial), Mechanical, etc?

I think I'm pretty much down to electrical, HVAC and the slab needing to be finalized, with everything else just needing review.

I'm sure that there's a better overall discipline that would apply to semi-private studio design/construction, but I'm not quite sure which.

Thanx,
Max

[franman]

He He.. LOL.. you need a consultant like FM Design..

No seriously, a GOOD local residential architect can handle a lot of the issues you list BUT most architects will not specify anything to do with electrical other than locations of devices and some light fixtures... Some will actually design HVAC but if they have the chops to do it quietly is another issue???

Specific slab and footing questions are either structural or, if small and 'typical' enuf, a good multi-discipline architect... smaller local firms are more likely to handle these types of review issues for you.. .Good luck! You may need it..

[xAm]

franman wrote on Tue, 31 October 2006 22:03

He He.. LOL.. you need a consultant like FM Design..

Don't I KNOW IT!!! Unfortunately the damn budget get's in the way... I know I'm a basket case since the lightning... does that potentially make me a charity case?  

Quote:

No seriously, a GOOD local residential architect can handle a lot of the issues you list BUT most architects will not specify anything to do with electrical other than locations of devices and some light fixtures... Some will actually design HVAC but if they have the chops to do it quietly is another issue??? Specific slab and footing questions are either structural or, if small and 'typical' enuf, a good multi-discipline architect... smaller local firms are more likely to handle these types of review issues for you.. .Good luck! You may need it..

Francis, you were dead on the money! (As if there were ANY doubt!) I found a local Architectural Engineering firm that's willing to go over the drawings and do the seal.

The engineer that I talked to immediately knew to be concerned with the quietness needed in the HVAC and the need for separate slabs for the rooms. He really seemed to be ready to deal with all of the issues.

I tried to send him my TurboCAD files exported to AutoCAD, but couldn't quite get all of the layers to open. Ever dealt with TurboCAD exports?

Thanx again!!!

MAx

[franman]

Glad you found a good local firm the handle it..

TurboCAD.. not in about 10 years.. sorry I can't be of help on that one... we're all AutoCAD and sometimes we have to deal with THAT MAC PROGRAM that some architects use (I refure to remember the name!!)..

sorry.