Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Building & Construction

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 06-11-2012, 08:47 AM   #1
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


Hey!

So in order to put in a new pipes in our basement, we had to big up a huge trench in our basement floor. It is around 12 feet long, 2-3 feet wide, and a 1-2 feet deep. (I'm estimating, I didn't dig it, nor am I looking at it right now.)

What do I fill it in with? Gravel and sand? Concrete? Gravel and Concrete? Gravel, sand, and concrete? What do I do.

Thanks!

martin1410 is offline   Reply With Quote
Old 06-11-2012, 08:56 AM   #2
MarginallyQualified
 
Join Date: Dec 2011
Location: Winston-Salem NC
Posts: 3,681
Rewards Points: 2,036
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by martin1410 View Post
What do I fill it in with? Gravel and sand? Concrete? Gravel and Concrete? Gravel, sand, and concrete? What do I do.
If you happen to have a pile of any of those handy... sure.
I've always used the pile of dirt that was right next to the trench.

TarheelTerp is offline   Reply With Quote
Old 06-11-2012, 09:10 AM   #3
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


oh.



really? and then just concrete for make a flat floor?
martin1410 is offline   Reply With Quote
Old 06-11-2012, 09:39 AM   #4
Architect
 
Join Date: Jun 2012
Location: Chicago/Kankakee Illinois
Posts: 154
Rewards Points: 150
Default

Huge Trench in Basement Floor


Concrete slab should be re-installed on a bed of compacted CA6 aggregate or similar product with compaction qualities.

To prevent heaving or settling of the slab, it would also be a good idea to dowel in the new slab to the old. If you ever plan on finishing the basement or putting down flooring, I would highly recommend this to avoid future issues.
jcarlilesiu is offline   Reply With Quote
Old 06-11-2012, 09:51 AM   #5
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


Dowel in? What does that mean?
martin1410 is offline   Reply With Quote
Old 06-11-2012, 09:55 AM   #6
Architect
 
Join Date: Jun 2012
Location: Chicago/Kankakee Illinois
Posts: 154
Rewards Points: 150
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by martin1410 View Post
Dowel in? What does that mean?


http://www.pavingexpert.com/concjnt1.htm

These dowels in the edges of the existing slab will prevent the slab from heaving or settling differently than the existing slab.

In a monolithic pour, the concrete is all unified and if any settlement occurs, it occurs as a body. Since a trench has been cut, you have essentially separated this slab, meaning that any settlement in the future may settle at different rates.

If you plan on putting down tile, carpet, or any other flooring system, or if you plan on inhabiting this space, the dowels will bond everything back together so that you don't have to worry about the new trench slab popping up or settling down.

Last edited by jcarlilesiu; 06-11-2012 at 09:57 AM.
jcarlilesiu is offline   Reply With Quote
Old 06-11-2012, 10:03 AM   #7
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


Aggregate and dowels can be found...where?

Home Depot?

Martin
martin1410 is offline   Reply With Quote
Old 06-11-2012, 10:09 AM   #8
Architect
 
Join Date: Jun 2012
Location: Chicago/Kankakee Illinois
Posts: 154
Rewards Points: 150
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by martin1410 View Post
Aggregate and dowels can be found...where?

Home Depot?

Martin
Yup.

CA6 fill would be cheaper to be ordered from a materials company who can deliver it to your drive way. You simply need to figure out how much cubic feet of fill you need.

When they trenched the basement floor, what did they pull out under the slab? If its clean gravel, and they saved it, I don't see any reason why you wouldn't be able to reuse it.

As far as welded wire fabric (reinforcing), and rebar, both of those can be found at your local home improvement store. You will have to drill the existing slab edge for the new dowels. Place them in the drill holes loose, and then set the other end in the wet concrete.
jcarlilesiu is offline   Reply With Quote
Old 06-11-2012, 10:12 AM   #9
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


Wow, okay awesome. The "gravel" they pulled out from the trench is mostly red/orange sand-like material, large rocks, and clubs of gravel stuck together with concrete. We still have it. It has been sitting outside for a month or two. Would you use that?

Martin
martin1410 is offline   Reply With Quote
Old 06-11-2012, 10:17 AM   #10
Architect
 
Join Date: Jun 2012
Location: Chicago/Kankakee Illinois
Posts: 154
Rewards Points: 150
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by martin1410 View Post
Wow, okay awesome. The "gravel" they pulled out from the trench is mostly red/orange sand-like material, large rocks, and clubs of gravel stuck together with concrete. We still have it. It has been sitting outside for a month or two. Would you use that?

Martin
The biggest issue with the base that you use is compaction.

For instance, using a silty soil that is very organic can lead to terrible settling. A concrete slab on grade is not able to span, thus its only as strong as its base. If the base settles, the concrete will settle as well.

Sand is not a terrible base as it drains well, but doesn't compact well.

If you don't see a bunch of settlement cracks or other indications of movement of the existing slab, the base may be fine. Its a judgement call without expensive testing.
jcarlilesiu is offline   Reply With Quote
Old 06-11-2012, 11:09 AM   #11
Just a DIY guy
 
Join Date: May 2011
Location: Southern California
Posts: 297
Rewards Points: 250
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by martin1410 View Post
Aggregate and dowels can be found...where?

Home Depot?

Martin
"dowels" in this case are usually #4 rebar (steel reinforcing bar) cut to the right length. Not wooden dowels.

And I've always heard they were to be epoxied into the existing slab, not left free like shown in that link. I think that may be more applicable to paving rather than residential slabs.

Last edited by M3 Pete; 06-11-2012 at 11:11 AM.
M3 Pete is offline   Reply With Quote
The Following User Says Thank You to M3 Pete For This Useful Post:
Ravenworks (06-11-2012)
Old 06-11-2012, 11:20 AM   #12
Architect
 
Join Date: Jun 2012
Location: Chicago/Kankakee Illinois
Posts: 154
Rewards Points: 150
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by M3 Pete View Post
And I've always heard they were to be epoxied into the existing slab, not left free like shown in that link. I think that may be more applicable to paving rather than residential slabs.
The dowels shouldn't be connected at both sides (meaning new and existing). Due to different locations and expansion/contraction characteristics, and because of normal shrinkage cracking, movement should be allowed in the horizontal direction.

The dowels are only installed to stop vertical movement (settling or heaving), and thus the rods don't need to be epoxied to stop this movement.

You are right that in a small trench, the free movement on the dowels probably isn't a big deal as it would be on a large pour. But no since in spending the money on epoxy since it doesn't serve a purpose.
jcarlilesiu is offline   Reply With Quote
Old 06-11-2012, 12:26 PM   #13
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


Okay, so it sounds like either I use the stuff that was in the hole and then pour concrete on top to make a level floor--pour a slab. Or I use something like this product to fill in the hole and then pour concrete on top.

And the concrete slab should be about 7 inches thick, according to the drawing above?

Martin
martin1410 is offline   Reply With Quote
Old 06-11-2012, 12:34 PM   #14
Newbie
 
Join Date: Jun 2012
Posts: 7
Rewards Points: 10
Default

Huge Trench in Basement Floor


To be completely honest, I understand the reasoning behind the rebarb, but that sounds like over kill to me. Am I just being a newbie? I am overseeing the remodeling of this house for men and women coming home from incarceration, and I'm not certain, I know any volunteer with a huge masonry bit and the experience to use it.

Thoughts?

Martin
martin1410 is offline   Reply With Quote
The Following User Says Thank You to martin1410 For This Useful Post:
TarheelTerp (06-11-2012)
Old 06-11-2012, 03:03 PM   #15
Architect
 
Join Date: Jun 2012
Location: Chicago/Kankakee Illinois
Posts: 154
Rewards Points: 150
Default

Huge Trench in Basement Floor


Quote:
Originally Posted by martin1410 View Post
Okay, so it sounds like either I use the stuff that was in the hole and then pour concrete on top to make a level floor--pour a slab. Or I use something like this product to fill in the hole and then pour concrete on top.
That is actually grout.

Use concrete, which is a mixture of some of the ingredients in the product above with aggregate (sand and gravel).

http://www.homedepot.com/webapp/wcs/...specifications

Depending on how many cubic feet of concrete you need, bagged mixes like this might be a pain. Then again, in a basement application, this might work well.

Quote:
Originally Posted by martin1410 View Post
And the concrete slab should be about 7 inches thick, according to the drawing above?
That drawing was just to illustrate the doweling technique. Match the current slab thickness.

jcarlilesiu is offline   Reply With Quote
Reply

Tags
basement, fill-in, foundation, hole


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Leveling a Basement Cement floor Tinkertom67 Flooring 0 08-14-2011 12:49 PM
Basement Floor drainage help wizardofgore Building & Construction 3 07-11-2011 10:42 AM
Finishing a cement basement floor with carpet and tile - no subfloor? vseven Flooring 2 09-21-2010 09:41 AM
Basement Floor Drain & Sewer Gas 1914 Home Plumbing 4 09-26-2009 03:46 PM
replace basement or dig trench w/tile? annie68164 Building & Construction 3 02-19-2009 06:17 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.