Pumping Concrete to Make a Basement Floor

Project: Bob's Shingle Style Home, Episode 5, Part 1

In the basement, groundwork is being laid for a useful finished space. To save headroom, plumbing waste pipes have been laid in trenches in the existing floor and a new concrete slab is poured over it. Ryley and crew frame a new dormer for the family room. Bob visits a Georgia-Pacific sawmill in Georgia.

Part 1: Pumping Concrete to Make a Basement Floor
A slab is poured in the basement and work is underway to add two new dormers to the roof that will match the original one. The concrete needed for the basement floor arrives by mixing truck and is dispensed by pump truck. Before the concrete is pumped into the house, the concrete finishers add a mixture of bentonite and water to the pump lines so that it will flow freely. Bob talks with Mike Walker, the concrete finisher, who is working with the crew to pour the concrete floor. It is an all-day job to spread it smoothly, let it set, and go over the work.
Part 2: Touring a Georgia-Pacific Lumber Mill
Part 3: Adding a Third-Floor Dormer to the Roof
This project centers around the remodel of Bob Vila's own gracious Shingle Style home in Cambridge, MA. It's a house with a lot of history and beautiful architectural details, many of which were obliterated in remodels of the 50s and the 70s. On the centennial of the house's construction, Bob gets together the best talents in the business to recreate and renew it to its former glory, making some important modifications along the way that will transform this into a dream house for today.

Also from Bob's Shingle Style Home

Hi, I'm Bob Villa.

Welcome home again to my Cambridge project. Today we're pouring a slab in the basement.

Even though there already is a slab down there it was pretty busted up and so we're improving matters down there.

And we're also working up on the top; on the roof. We're cutting in for two new dormers at the third floor level and today we're gonna be actually going to be cutting through the roof as well as showing you how you frame the dormer structure. And a trip down to Georgia to visit the mill where they make all the dimensional lumber.

Stick around, it's good to have you home again.

We're receiving the concrete in a regular mixing truck, but we've also hired for about five hundred dollars a day a pumping truck. And the pumping truck really is worth it because otherwise you'd spend more than that just in labor trying to get the concrete material to where it's going.

Before any of the concrete starts coming through the pumper, they add a mixture of about a tablespoon of Bentonite, a type of clay mixed with water, which creates this slimy liquid and as that goes through all the hoses it'll make the concrete flows through there very freely and this will be a job that will be going on, all day long.

Now I'm standing in the area of the basement where all of the plumbing pipes that were laid last week come together and you can see the gravel, that was put into the trenches right under our moisture barrier and of course this cast iron piping was laid to take the waste pipes from the new bathroom locations as well as the kitchen and everything leads back out here to the street. But right now lets hook up in here with Mike Walker, who's in charge of the crew that's putting concrete down. Hey Mike, you're in the area which is gonna be my woodworking shop, and so all of these PBC pipes stem through are for the different tool stations where we'll have a sawdust collection system, but let me ask you about some of the work that has already been done here like around everyone of these structural piers. What is this material that you've wrapped around?

This is a. fancy material. And what we're doing is, concrete expands and contracts with the temperature of the -

And -

And so it's -

The flexibility.

- coming up through all these piers. This will prevent some of the cracking .


Okay. And don't you need to put in wire reinforcing when you're adding a slab on top of a slab like this?

Not really, because this is very strong. You've got a sub floor here already. That will take all the stress. Just top it to make it level.

Yeah, yeah. And also, what's the mix? What's the PSI of the mix?

We have a 3,000 pound PSI. And we have two percent par receptor to add to the setting time.

Okay. Now this is an all day job for you guys.

Yes, it is.

Not just from the point of view of spreading it, but letting it -

Letting it set and then we come back and we have trowel it out a couple times for you.

Alright. Well, we'll just watch for a bit and then we'll come back later in the day to see how power trowels move. Well, that basement's gonna be terrific and we'll put in a stairs that'll go directly into the kitchen.

And then, of course, the rest of the house used the original staircase here, which goes up to the second and to the third and the third is where the action is today.

All right. This is an exciting spot.

We've already cut out one of the holes over here.

Hey, Riley.

Hi, Bob.

Lookin' good.

We've already cut out one of the holes of two that we're making to create new dormers that'll match the one that was originally here at the other end of the house. And we're gonna be talking lumber today.

We gotta break for some messages. But, when we come back, we're gonna be in Sterling, Georgia visiting a saw mill where they make all the new dimensional lumber.

So, stay with me.
We're visiting here at the Georgia Pacific Softwood Lumber Mill, and Randy Benoni will be our guide.

You know, we're looking at probably the biggest pile of timber you'd call it, because it hasn't been turned into lumber yet, that I've ever seen. How, how many cords of wood are there?

Well, Bob, you're looking at roughly two thousand cords of southern yellow pine timber.

And when I think of a cord, I think of it in terms of firewood and its dimensional measurement - four by four by eight feet. This is different, right?

Right, because we don't have the ability to measure it that way, we buy it by weight. Roughly, fifty-six hundred pounds per cord. And what you're looking at, like we said, was two-thousand cords. Enough to keep the mill operating for about a week.

For about a week?

Yes, sir.

Now, is this grown like on tree farms?

Yes, sir. It's what we call plantation timber. There's very little virgin timber left in this part of this country. So it's a renewable commodity.

Yes, sir. It's planted and re-harvested every twenty-five to thirty years.

So it takes twenty five, thirty years to grow these lengths, which are maybe forty feet?

Yes, sir. Forty feet or longer. And probably anywhere from eight to ten inches in diameter.

Fabulous. Now what's the first step in turning it into dimensional lumber?

Taking it from the log deck here to the sawmill, where we go through the debarker.

The debarker?


Before the debarker, Bob, the logs have to be cut to length. This is a decision that's made by a human operator -


- to try to minimize the amount of waste here.

So you've got maybe forty foot logs and you're trying to get sixteen foot lengths or twelve foot lengths and the like.

Exactly, to maximize the use of that forty foot log.

That saw blade looks to be...what's the diameter of that blade?

That's a 72 inch in diameter blade, Bob.


Now, Randy, explain to us how the debarker works.

Okay. Bob, there's three steel cambios that are cylinder in shape, that literally eel the bark off the log. There's 5 carbide blades that grab the log and rotate it. As the cameos rotate and peel the bark off.

What do you do with all the bark?

Now it goes on to the pulp mills for fuel.
Is any of it used in landscaping?
Yeah , some plants send their bark on to be used as mulch.

Yes it is.

Okay, then what's the next step?
After coming from the debarker, being sorted and going through the metal detector, then it's on to the actual sawmill.
Why does it have to go through a metal detector?

Well, in this area there's a lot of hunting, Bob. Hunters put up deer stands, may put nails in a tree, or even bullets, or shotgun pellets.

Right. Yeah, yeah.
That of course would ruin your blade.


Now what is the lady doing in the control booth up here?

She is actually sorting the logs, by size and length.


So this is the first place where they cut logs right? Where you've got blades going?


This is where the logs enter the mill.

I can't hear you.

Let's go up in there.


It's just too noisy to talk out there. Now this is first place where the log actually encounters a blade, but what do you call these red turning things there?

Okay, those are the feeders, Bob. The log is coming through the optimizer where the computer is determining what's going to get cut out of the log.

The feeder is then sending it into the chip and saw.

So this whole assembly here is called a chip and saw?


Because its chipping away at the sides of the log and then its also sawing it.

Right, it's going to saw two sideboards off of the log and its gonna leave you with what we call a cant.

A cant? Which is essentially a squared off log.

A slab of lumber. Exactly.

And where does it go next?

From there it goes through the gang saws. Who determines what you're going to get out of this cant?

The computer does. It's all determined by the computer. It makes several calculations, so that it can maximize what comes out of every individual log. Based on yield and on possibly market conditions.

How do market conditions effect what you're deciding to cut here now?

Well the computer helps us to determine what to cut.

Market conditions tell us what the consumer is needing at this time. So therefore, we program in what market conditions are.


The computer will take that into consideration and help us produce what will bring in the optimum amount of money for this particular sawmill.

Okay, so the computer's actually controlling this gang-saw.


How does the gang-saw work, how many blades do you have in there?

What happens is you have your four inch, or six inch or eight inch cant that are fed into the gang-saw. It's a series of circular blades.


That then take that cant and slice it into two by fours, if it's a four inch cant, two by sixes, six inch, so on and so forth.

And here you go, you're getting Stud lumber coming out the other end.

Exactly you have a slab goes in one side and a 2X4 comes out the other.

Now, what's happening here? Is it a sorting operation that goes on once it comes out of the gang saw?

It goes across the change where it goes into the sorter to be sorted by dimension and length. And from there it goes on to the dry kilns.


So once it's all been rough cut you stack it and space it like this so that you can dry it, right ?

Right, it comes from the sorter, Bob. And this is what we refer to as our rough green lumber and it's ready for drying.

It's goes into the dry kilns where it stays at an even temperature of 350 degrees for about 18 hours.


When it comes out we refer to it as our rough dry inventory, and then it's stacked and set aside for about two weeks before going on the the planer mill.

That of course is, the secret of good construction lumber is to keep it nice and dry. What's the percentage when it leaves the operation here?

We dry it down to nineteen percent or less. Your moisture content can be your single largest problem in lumber.

Yeah. Now, I've also heard that you've got a terrific safety record here at this plant.

Exactly. This plant is better than five times the national average. They received the VIPs award last year. And, this is all recognizable in the fact that you have to wear the colored vest...


The goggles, the hard hat, and the special shoes.

Let's go and take a look at that planer operation.


Alright Randy, once it comes out of the kiln, what happens next?

After if comes out of the kiln, it's what we call rough dry lumber, Bob. It goes from the kiln to the planer, where it goes across the chains as it's being sprayed by a light mist of water to control the dust.


From there it's fed into the actual planer and surfaced on four sides. Thus the term S4S lumber.

S4S. There's four knives working at it at once?

Actually there's four heads, with knives on each individual head, surfacing the lumber on all four sides at one time.

OK. And then what's happening over here at this station where these two fellows are working?

OK, the lumber is now Coming out of the planer, and going across what we call the grading table. Where each grader is given just a few seconds to look at each individual piece. Now, you have two graders there, so they're looking at every other board.

So these men are really the quality control of the operation.

Exactly, they can make or break a saw mill.

And what are the different grades that they're dealing with?

These particular graders are dealing with five different grades today. Dense select structural being the highest grade or truss lumber. Number one common and number two common being your framing lumber or lumber that goes on your treaters.

And number three common and utility is what we call industrial, that goes on to pallet manufacturers and crate manufacturers, and so forth.

Okay. And then all of this sorting is done automatically.

Yeah, after it leaves the grading table.


The scanner reads the grader's mark, and it puts the appropriate stamp on each individual board, and then goes across the timing chains which dropped in the individual bins by dimension and by grade. From there it's... Drops and goes to the bander, and it's banding the actual finished packages.

And ready...

And on to market.

And ready to go on to market.


Randy, it's a pretty impressive operation. Very streamlined and clean. Now, how much output do you have, in board feet let's say?

Bob, this particular mill about 1.6 million board feet a week. As a company with 27 mills, about 45 million board feet a week.

A week?

Yes sir. Or roughly enough to build the city of Charleston every week.

Every week?

Every week.

That's pretty astonishing. Thanks for the tour.

Yes sir, anytime.

Stick around, we'll be right back after these messages. Alright.

Well, from the sound of it Riley, you got rid of all the nails that might have been in the way there.

Yeah, we sure did.

So we're making the second opening here and as I was saying earlier in the show our objective is to create another dormer at this third floor level, just like what you see behind me over here.

This is an unusual set up, because if you look below there, you'll see there is a shed dormer on the second floor with a very nice sprung shed roof to it.

If you go up to this level, they added a little hip roofed dormer with three windows and it's a charming detail. We're gonna recreate the exact same detail over here.

In fact Riley, we could let the fellows from Fort Hill, get the rest of this opening headed off and we could get started framing this one over here.

Yeah there's plenty to do here.

All right. Come on.


Let's get the pieces.

All right. We've pre-cut and prefabricated some of the pieces for this dormer. And these triangles are what we call the cheeks. You ready to put this one up?

Sure are!

We've got our marks exactly where it goes. It goes to you a little bit?


Right in there, I think. I got a mark right there.


And so we'll just shoot it into place.

All right. Now I'll do the same on this side.

OK. And I've got a mark down here. Right there?

Yep. I'll get out of your way. OK.

And ready?


This piece connects the two.

There you go.


Alright, now this piece goes on the face.

OK. Mine kind of looks good.

Yeah. This one does too.

And these are called the sole plates?

Right, sole plates. They just lay right on the sheathing, the roof sheething. It needs to come over this way a little bit.

Okay. How's that?

Nope. There it is, that's in place.


I'm gonna nail in mine.

Okay. So, this is the ridge.

This is the ridge.

And I'll hold it in place for you.

You gotta tack up here. And then --

Look at this.

Is the middle rafter the one for the Yeah. That's the common that goes right up against it.

The common rafter.

Okay, and you've got that?

Exactly where it goes.


How's that?

That's beautiful.



And ... Here's the right side.

This goes this way. This is ...

There we go. That should go right in there.


Alright, and these are the hip rafters.



Pretty nice fit.

Very nice.

You get those, I'll get the bottom


Alright now, these are technically rafters. What kind of rafters are they?

Going from the hip to the plate, it's a jack rafter.

A jack rafter.

Alright. Well, the geometry is in place. It's basically a pyramid from this side.

Yeah, it's nicely cut together. Are you ready for some sheathing?

Yeah, sure am. Okay. And this falls shy of the top.


Because it's a four foot sheet of plywood, because this is as far as it goes.
Okay, two sides and this completes the pyramid.

Does it fit?


All right.

Good, we're gonna break for some messages, when we come back we'll look at that cellar concrete floor. Stick with me.

Okay, we're back down in the basement and in real time, we've had what about six hours go by Mike?


So you've had a lot of time in finishing.

Yeah, now there's been a lot of work involved in getting to this point. And now your son Mike is doing the final steel trough work here.

That's right.

What does this achieve?

This makes it denser. And a harder finish is a smoother finish.

The steel trowel will actually let you have a glossier kind of tighter finish, right?

That's right. We'll do this a couple of times.

Yeah .

We will come back again after this.

How long should we wait? How many days before we can come back down here and
have men doing other work?

I would give them one day.

Just one day?

Just one day only.

Great! Thanks, you guys have a done a wonderful job. We're running out of time.

Come home again next time, when we'll be done with all of these structural repairs. We'll be putting up some of the new partitions, wooden studs and metal ones.

Also a tour of the Longfellow house, one of Cambridge's most beautiful
historic homes. Until than I'm Bob Villa. It's good to have you home again.



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