Tuesday, January 15, 2013

"We Want to Keep the House From Falling Down"

Good words to hear when talking floor plans with a structural engineer. 

Because we want to remove all the walls on our main floor during our upcoming renovation, we have to replace them with strategically located posts and beams, both steel and LVL.  We were introduced to an amazing structural engineer when we dug out our basement...so we invited him back to help us on the main floor project.  Nothing like continuity when it comes to structure.

I mentioned in my last post that we had a sticking point in our floorplan. 

This is it.  Walk through the first doorway above and you're in the living room.  On your left is the wall separating the living room from the dining room.  It's super hard to get a good picture of it.  So I circled it in the floor plan:

Why would this be a sticking point?  It isn't load bearing.  It's not integral to the structure.  Unless it's connected to a wall that leans.  Yes, that handwritten note on the floor plan above says "leaning wall" with an arrow pointing to the outside (not shared) brick wall. 

Our non-load bearing wall is a buttress. (SFX: groan)

That lines up to the second step of our staircase.  (SFX: louder groan)

I've been worried/freaking/frazzled about how we're going to remove that buttress and support the outside wall without putting a post against the shared wall and cut up our staircase. 

My designer, Kirsten, was optimistic.  See how the buttress wall is gone, the outside wall has a spot for a post, but the staircase is untouched?  Love that. 

And so did the structural engineer.

Truth is, we got lucky.  We thought about removing this tricky wall -just between the living room and dining room- before we knew it was a buttress.  We were going to demo it when we dug out our basement.  But our engineer noticed the lean.  

Long story short, he had us put a steel beam (the width of our house) in the basement ceiling directly under the buttress.  This way, if we ever wanted to open the living room to the dining room completely, we could build a steel frame and tie into the beam below using posts at the outside wall and in the hallway. 

But now we won't have a hallway....or a place to put a post....

Cue our engineer:

This is my bad drawing of his solution.  It's a cross-section of our house if you chopped it top to bottom through the buttress wall.  I've drawn the steel and the staircase. You can see in the basement, we already have the posts and beam in place.  What's on top of it is his idea...

At (1), we would place a steel post "on top of steel post & beam"
At (2), the steel beam and steel post would have a "welded joint" for highest strength
At (3), the beam would fit "into shared brick wall"

I'm not an engineer, and I can't remember the exact words.  But because the single post and beam would be welded in place and at a right angle, it would have the strength and counterstrength to hold the house and the leaning wall in place.  Like a buttress.

Music to my ears.

So we can get rid of this.

And keep this.

I got plans for that gorgeous baby gate, to-die-for laminate on the steps and aren't-you-jealous-of-me ceramic tile.  Complete with missing grout.

So that's it for the sticking point.  Solved.

What about the rest of the support?  Aren't there like two more rooms past the buttress wall?  Yes. 

Luckily enough, we know our house is typical in one way.  It has wider foundation walls.  See that lip behind gorgeous baby gate #2?  I cursed that thing in the basement dig.  Now I could kiss it.

A post will rest on that lip about 2 feet back from the right edge of this picture, hidden in the powder room wall.  The other post will hide in the kitchen, on the outside foundation wall.  And if all goes well, the beam will hide in the ceiling joists. 

So now, with the structural situation figured out, all I have to do is get a family of five ready for demolition day.....!!!!!!

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