Redesigning the Third Floor

Bob meets with architect Gregory Rochlin to discuss the third-floor structural redesign.

Clip Summary

Bob meets with architect Gregory Rochlin to discuss the third-floor structural redesign. Additional supports will be added to the existing roof to allow for the snow load, which will occur now because the improved insulation will prevent heat from escaping and melting the snow. Also, Bob intends to plaster the new ceiling, so to safeguard against any cracking, the roof will need to be stiffened to handle the extra weight.
Alright, we're back , and we're up on the third floor now. And we're joined by Gregory Rochlin , the project architect. We've got a real interesting situation up here, hi Riley.

Hi Bob.

You just doing takeoffs, huh? We've got a situation where we're trying to create a thirty by twenty-six foot room, right?

That's right, about that size.

About that size, which will be a family room. And, we've removed a lot of partitions. We're down to a bare roof. We've got collar ties that hold that roof together.

That's right.

But we want to go one step further. We've got on the outside of the house a beautiful set of dormers that serve the second floor, and they're large dormers.

They have shed roofs on them, and if you look at the very first one closest to the street, it has an addition on the top that services the third floor...

That's right.

With a little hip roof
on it.
And we want to recreate both of those situations here for the benefit of this room. So, it's complicated framing that we're doing here, right?

There's a number of problems. Originally, this roof was never intended to take a real heavy snow level. Because the house was uninsulated. So, in the turn-of-the-century, the heat just went to the third floor, melted the snow, snow came off the roof.


Now, we're gonna heavily insulate the roof. It's gonna have a big snow load.


We need a stiff roof, because now we're going to plaster the under side of the joist.

That's the other thing.
The original situation, you had, small rooms that had flat ceilings with the plaster. Now, if you put the plaster board directly on to this roof, you gotta stiffen it so that it doesn't crack.

And, just to make it even more difficult for us, we're removing most of the roof framing on this side of the roof.

Yeah. This will all be cut out. And how does the structure work? I mean, they're up against each other right now, right?

Well originally, it's like my my fingers are just a group of rafters. They're pushed against each other. Imagine my other fingers of the collar ties and keeping the roof from spreading.

Now we are putting out these, well these are micro lambs right?

That's right.

And so we're creating doubled up situations here.
How many of these will we put up?


There you go. Do you need this to persuade it?

Oh, I do.

All right.

And if you look at the behind Greg here we've got already in place.
Explain how the load gets transferred down.

Well, this big heavy rafter is now taking, doing the work of all these rafters over here, which are going to get headed off for the dormer. So all the load from this part of the roof comes down to this rafter, and then comes on this, what's called a cripple wall. Which originally brought some of the roof flow down to this floor, and the rest of it went down this gambrel rafter. Now, because we've got a much heavier load, we're going to have to increase the size of this, increase the size of this stud and put a beam underneath the floor to take the additional loads. And with all this additional framing, now the roof will be stiff enough so when you plaster it, your plaster won't crack.

Right . And you got to go to a great deal of trouble. It's an enormous amount of work. The only way to avoid this is don't hire an architect. Just kidding. OK.

So I guess we've got one in place and another one to go on the other side. Now on the other side of the roof itself, you've built some temporary walls. Right?

Well, we're gonna have to increase the depth of all these rafters.
One, to make them stiffer, and two, to give us enough room to get insulation in.

So, you 'll sister something on.

We'll sister something on. In order to do that, we have to take this triple wall out so we can slide the rafters up. And so this is two temporary triple walls. One here and one here. It will hold the roof in place so when we take this out, your roof doesn't collapse.

Thanks for doing all the planning work, Greg.

Thank you, Bob.

We gotta break for some messages. Don't go away. Well, I'm afraid we're running out of time for this week. Come home again next time when where gonna be working in the basement.

Actually, we're pouring a two-inch slab throughout the whole basement area, and that includes first putting in some cast iron piping for the plumbing.

Also, we're gonna be framing, putting the finishing touches on framing the dormers that we were just looking at today. And taking you down to Sterling, Georgia, where we're going to visit a plant where they cut down all that framing lumber.

Til then, I'm Bob Vila. It's good to have you home again.