[MKCOM1]

Okay here goes;
I have a typical Chicago bungalow 1920ish brick contstructed. The basement/1st floor joists are 2x8s 16" ocsupported by steel and span the width of the house or 24' and rest at their end on the exterior brick walls that at that point are 4 courses thick. On the first floor I am wishing to tear down about 14' of load bearing wall to double the size of the kitchen. Said wall rests above steel beam. The second floor attic area uses 2x8 joists and spans the same 24'. Attic area has been dormered so that 2/3 of 24' span is now living space. Load bearing exterior/outside wall on one side and knee wall on other. Based on my limited knowledge it would appear that the exterior brick walls carry the full load of the roof short any minor support of the knee walls.
My thought was to remove any partition walls 1st flr, and build temperary support walls parrellel to load bearing wall about 3' away on both sides and remove load bearing wall. I would then cut 2nd floor joists sized to the width of the needed beam, insert beam supported by double/2x4 or 2x6 columns and use joist hangers on second floor joists. Based on lvlbeam tables I read a 3 1/2 x 14 beam or a 5 1/4 x 11 1/4 required. Based on southern pine tables I read 3 1/2 x 14 required. Can anyone verify this?
2nd question. What type of overall dimension should I be using for the column supports, 2 2x4s, 3 2x4s or 2 2x6s etc? Additionally these columns will not be resting on the steel supports below. This could be an option but have to recheck the allignment again. If not I could open the 1st floor up and sister the 2x8 1st floor joists on either side and then install blocking, multple times between them resting on the steel, above which the column would sit. If by chance the column is offset slightly, no more than a foot. Would this still be acceptable.
And lastly, in trying to keep as much ceiling height would a steel T beam be acceptable. In this case the cut 2nd floor joists would rest on the inverted T and I assume blocking installed staggered in each joist space.
I have undertaken many jobs in the past and feel quite capable for this but have never attempted such a job. Not that its a problem and overall the renovation consists of 60-70 % of the first floor and am really looking forward to the work. Any help is much appreciated and thank you in advance. Ken

 

[AndyGump]

This is a DIY home light construction (very light construction) site but it is not a Do It Yourself significant structural change to my house engineering site.

There are many other things coming into play when you try to do an important change like this to your house. Things that require an engineer to design if it is out of what is called prescriptive code design.

You need plans and permits for something like this and even if you are in a place where plans are for some idiotic reason not needed then in my opinion you ought to seek out a professional to design the structure for you. If you want to do the actual construction yourself it is still fraught with some danger and maybe better left to a pro but that is your call.


Andy.

 

[Mingledtrash]

You absolutely need an engineer for this. I do this kind of stuff for a living and would have a fairly good idea of what is needed as far as the work but i would still never attempt it with out an engineer telling me how many and how big of which material. There are just way to many variable involved from dead load to live load to wind. You have fasteners, hangers, point loads, shear values, and many more things to take into consideration.