30x40 build advice

[kylemac]

Hey Guys,

Just finished up getting my new separate driveway to my shop in, lot all cleared, wood all split and the site is ready to go for foundation and build in the spring, I just finished up my drawings and got everything approved by the township, now just to wait until winter is done. A few small things ive been looking at have been doing ICF for my foundation instead of block? my foundation is going to go 2' above grade with 10' walls on top for 12' ceilings, reason I was considering the icf is im going to do radiant, live in a cold climate and was planning on putting insulation on the block anyways, obviously a solid formed wall is much stronger and would have a better r value with the ICF, just not sure how cost effective it is and if its really worth spending the money, I have no problem spending money on insulating to save me money later, but not sure if this will help me out. my 2nd thing is that im looking to put in an I beam for a trolley and hoist in the shop, going to do it width wise of the building so the length of the beam would be 30', it will be strictly mechanical use and have no support for anything as im using engineered trusses, I want to get quotes on the beam but have no idea what size I need or type. I think a beam that would be able to support the hoist lifting 1 ton would be lots for me. Ive been told I would need a S12X31.8 to support a 1 ton load at that span. Anyways if anyone could shed some light on this stuff for me that would be great!

 

[matt_i]

ICF is one fairly easy way to do your own concrete work, at least for stem walls. You'd still need to pour a footer for the blocks to sit on. I'm not convinced that the 2" thick R-10 (?) insulation is really gaining a whole lot on 140 feet of 8" exposure (its 93sqft of wall at R-1). Insulating under the floor is a bigger way (1000sqft in my case) to gain on the R-1 concrete.

This isn't a total apples-to-apples comparison because the exterior temp bathing the stem wall (variable probably 20F for a winter average) is a different temp than the earth under the slab (probably solid 45F).

I did that but I stripped off the top layer of foam inside & out to give a traditional exposed concrete finish. I struggled with what I could use to protect the exterior and interior foam that was good for ground contact and ended up going bare.

You'd be well-served to place a "cap channel" on the I-beam on a long span. Think of a channel that sits on top of the S-shape, legs down, sort of making an elaborate "T" section. Since the top flange isn't fully braced that will help increase "Iyy" for compression loads that could be misaligned on the top flange. You also need to prepare the wall structure for the potential side/misalignment loads. I recommend using flat strap X-bracing, like Simpson CS-series. Design your beam for L/480 deflection. No sense in having a strong-enough-but-not-rigid-enough beam where the rated load always rolls downhill to the center.

 

[kylemac]

ICF is one fairly easy way to do your own concrete work, at least for stem walls. You'd still need to pour a footer for the blocks to sit on. I'm not convinced that the 2" thick R-10 (?) insulation is really gaining a whole lot on 140 feet of 8" exposure (its 93sqft of wall at R-1). Insulating under the floor is a bigger way (1000sqft in my case) to gain on the R-1 concrete.

This isn't a total apples-to-apples comparison because the exterior temp bathing the stem wall (variable probably 20F for a winter average) is a different temp than the earth under the slab (probably solid 45F).

I did that but I stripped off the top layer of foam inside & out to give a traditional exposed concrete finish. I struggled with what I could use to protect the exterior and interior foam that was good for ground contact and ended up going bare.

You'd be well-served to place a "cap channel" on the I-beam on a long span. Think of a channel that sits on top of the S-shape, legs down, sort of making an elaborate "T" section. Since the top flange isn't fully braced that will help increase "Iyy" for compression loads that could be misaligned on the top flange. You also need to prepare the wall structure for the potential side/misalignment loads. I recommend using flat strap X-bracing, like Simpson CS-series. Design your beam for L/480 deflection. No sense in having a strong-enough-but-not-rigid-enough beam where the rated load always rolls downhill to the center.

Thanks for the reply matt, so from what you replied about the ICF I think I described what im doing poorly, its not just a slab but full foundation frost walls and a footer because of where I am, so I will have footings down at 4' and then 6' of ICF wall on top of my footings, so I will end up with 2' of my icf foundation wall above grade which will also act as a stem wall. The foam being both sides of the form is a R-30 the manufacturer says, 2" on either side, so there would be 2' at the total length of 138' of exposed ICF or 276 sq ft coverage I would be getting with the ICF that would be above grade.

 

[MushCreek]

Most 'standard' ICF runs about R-24, with 2-5/8" foam on each side. Bear in mind that the wall will be very thick; nearly 12" for 6" ICF. How will you transition the framing so that you don't have a huge step?

 

[ConCretin]

I did an an analysis when I built my place and decided that for below grade walls, ICF didn't make financial sense compared to a standard cast in place wall with 2" of rigid insulation. Plus you have the added cost of covering the exposed foam and dealing with the width discrepancy between the ICF and the would framing above. ICF's might be a little easier as a DIY project though.

With regard to your lifting beam, companies that sell end trucks, trolleys, etc publish charts showing beam sizes for various load ratings and spans. You'd have to ensure the beam itself was properly supported but this could help you size your beam.

https://www.harringtonhoists.com/tech_support/edocs/EDOC 0367 rev02.pdf

A google search for 'bridge crane beam sizing' will turn up more info.

Good luck with your build.