Forno Bravo Forum: The Wood-Fired Oven Community

Forno Bravo Forum: The Wood-Fired Oven Community (http://www.fornobravo.com/forum/)
-   Tools, Tips and Techniques (http://www.fornobravo.com/forum/f28/)
-   -   Pour two slabs at once? (http://www.fornobravo.com/forum/f28/pour-two-slabs-once-18385.html)

Tomweb 09-18-2012 06:56 PM

Pour two slabs at once?
 
Hi all,

I'm hoping to pour here in the next few weeks, thanks all for participation on this forum, it's invaluable!

Here's a thought. I'm considering a truck pour in a few weeks. How outrageous would it be to have the foundation slab _and_ hearth base poured at the same time?

I'm planning to frame the hearth base, resting it on 4 x 4s on the ground nearby, where I'll screed, finish, level and cure......A couple (?) weeks later I'll use my front end loader to web sling it onto my block supports?

It'd be a gentle operation but I feel it could be done properly and safely with a few extra bodies....

I see a possible savings of several hours and it takes advantage of having the truck in place.....once....., as a newbie I should ask: ."...what am I missing here?"

lwood 09-18-2012 09:38 PM

Re: Pour two slabs at once?
 
The perlcrete mix is a little strange to work with but it may be possible. Better have the first slab well supported.

GianniFocaccia 09-19-2012 01:33 AM

Re: Pour two slabs at once?
 
As long as you have the lift, it sounds like a practical project. I would pour the support slab with 90 degree bends in the rebar (pointing down) around the perimeter. This way when you lower your slab onto your blocks the rebar drops into the top-most concrete-filled course.

lwood 09-19-2012 02:21 AM

Re: Pour two slabs at once?
 
Why not pour it in place?

brickie in oz 09-19-2012 03:06 AM

Re: Pour two slabs at once?
 
Quote:

Originally Posted by Tomweb (Post 138767)

I see a possible savings of several hours
...what am I missing here?"

Your going to risk your build for a couple of hours? :confused:
What am I missing here? :confused: :confused:

Tomweb 09-19-2012 03:18 AM

Re: Pour two slabs at once?
 
Iwood, My reasoning has to do with efficiency. I figure while the truck's here I'll go ahead and double pour.
You also bring up a point of discussion regarding your perlcrete comment

Quote:

The perlcrete mix is a little strange to work with
My approach was going to be hearth slab followed by insulation layer, I better drop back and review suggested techniques.

John, thanks for the bent rebar suggestion, I like that idea!

jeeppiper 09-19-2012 05:35 AM

Re: Pour two slabs at once?
 
sounds ambitious!

1. Did you estimate the weight?

2. Once you drop the slab on top of the foundation, how will you get the slings out from underneath?

3. Is your hearth slap just the pearlite mixture? Doesn't seem structural even with the rebar. Or will you have a structural slab supporting a pearlite mix?

4. Can your front end loader "reach" far enough to center the slab over top of your foundation base?

Gut reaction is not to rush it and do it in two pours.

I had a truck pour my foundation...and I used bags for the hearth.

Gulf 09-19-2012 05:56 AM

Re: Pour two slabs at once?
 
Quote:

Originally Posted by Tomweb (Post 138767)
I'm planning to frame the hearth base, resting it on 4 x 4s on the ground nearby, where I'll screed, finish, level and cure......A couple (?) weeks later I'll use my front end loader to web sling it onto my block supports? "


I would form 4 pad eyes out of rebar and wait at least 28 days before placing it. The hearth slab will be much stronger then and considerably lighter. After placement, the pad eyes could be cut off even with the slab.

Tomweb 09-20-2012 07:55 PM

Re: Pour two slabs at once?
 
Bricke- Iwood- Gulf- Jeepiper!

All good questions…..here’s what I figure.

With _great_respect and admiration for all who have completed the task and are enjoying the fruits of their labors……I don’t think I’m risking my project to save two hours. If, after discussion and serious consideration this idea is flawed, I’ll drop back and make two separate pours. Don’t we all look at our tasks and projects with an eye towards efficiency whenever possible?….If I can have the hearth slab in place, ready for an insulating layer and firebrick after a month, I’ll be stoked! (Pun intended...)

First, my plan is to pour a concrete hearth slab with an insulating layer over that, either a perlcrete mix or appropriate foil faced foam boards

Second, regarding weight: I have calculated the following: My 6 x6 x 4” hearth slab measures out at about 12 cubic ft and will run about 1700 lbs ( Yes, my loader will handle load and reach…but very good questions)

Here are my weight calculations, based on Sakrete:(Would not a poured mix be very close in weight?...I'll call the delivery guys and ask that one...) 80# bag of Sakrete is .6 cu ft… 12 cu ft would require.20 bags = 1600 lbs + rebar…. I’m thinking 5/8”, probably 5- 6ft pieces and 5 -7’ pcs for a total of 65 ft @ 1+ lb / linear ft = 70 #
Gulf - good thought on curing time. I knew it could use a good, damp couple of weeks. Of all the caution I exercise, letting the slab cure properly is my best bet to avoid a fracture on sling day…….btw your album is awesome, I’ve been through it a number of times to try and know what I think I know….. and will return again, I’m sure!

Quote:

Once you drop the slab on top of the foundation, how will you get the slings out from underneath?)
...............Jeepiper. I hope I don’t “drop” the slab at all!!! I figure load slings in two places that’ll allow me to set it in place, supported by the extended rebar….right? As this slab is gently set in place I plan to pull the straps out from around the slab. I’ll lower the bucket and the web slack will allow me to pull the straps, as there will be approximately a 1” gap between hearth slab and supporting block.

You all are great….Thank you for helping me work through this again in my head. I’ll keep you posted and stay in touch! Many thanx!

brickie in oz 09-21-2012 12:55 AM

Re: Pour two slabs at once?
 
Quote:

Originally Posted by Tomweb (Post 138889)
appropriate foil faced foam boards

It'll melt. :D


All times are GMT -7. The time now is 05:41 AM.

Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
2006/10 Forno Bravo, LLC