Basement building 101

Agility Customs

Well-Known Member
Vendor
So my wife wants the basement finished and since she abuses me she gets what she wants. I can finish a basement no problem except for when it comes to knocking out a wall. I know when we knock out this wall it will need a beam of some kind to support the weight of the house. What are my options and how do I figure out what size of beam I need. We want to open up that doorway to about 12-14’ wide.

High tech drawing attached for your viewing pleasure.
 

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N-Smooth

Smooth Gang Founding Member
Location
UT
A beeg one. Y'welcome.

Really though what size is the beam over the door to the right, 2x10? 2x12? Are you going to put the wall where that door is currently?
 

Stephen

Who Dares Wins
Moderator
So my wife wants the basement finished and since she abuses me she gets what she wants. I can finish a basement no problem except for when it comes to knocking out a wall. I know when we knock out this wall it will need a beam of some kind to support the weight of the house. What are my options and how do I figure out what size of beam I need. We want to open up that doorway to about 12-14’ wide.

High tech drawing attached for your viewing pleasure.
It's never to late to ask for help:


:D
 

Kiel

Formerly WJ ZUK
I used an LVL beam when I did mine, you can find the calculators online. It's just a basic laminated beam. Permit or no?
 

Kiel

Formerly WJ ZUK
The laminate beam calculators are pretty accurate. I think mine is 25 feet long and ran me about 1k
 

STAG

Well-Known Member
We’re adding a beam right now too but not because of widening a wall opening, but because the floor of the upper level has bowed with a sag over the decades. Cutting the ceiling in prep for the beam to press up directly on the 2nd level floor joists.

A5585593-AAFE-4996-A6B6-D6F3A0D81C09.jpeg
 

Mouse

Trying to wheel
Supporting Member
Location
West Haven, UT
I hope to build walls and finish portions of our basement in the future. The beam calculators are a great resource. Do you mind sharing how you build the walls, especially around windows? I'm not a carpenter at all.
 

shortstraw8

Well-Known Member
You should be able to pull the final submitted plans for your house from the city/county, then have an engineer or do really good math find a few specs. You want to get the floor load psf to determine strength of the beam needed and if footing work needs to be done since the psi will change. If you use lumber most manufactures have their specs available or get the equivalent in steel ibeams. My guess is, if you have one story above you will be 2 1 3/4" X 9 1/2" lvl and and with 14' span take your current studs or 14' / 16" centers and split them on each side same width of the lvl, probably 6 2x4s if the lvl is 1 3/4".

You will basically build the same wall for bracing on either side (the company I worked for we always braced both sides) you want it tight so no sagging happens, remove existing and get ready for hernia causing lifting of the heavy beam.
 
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