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 05-30-2011, 02:40 PM   #1
Newbie
 
Join Date: May 2011
Posts: 1
Rewards Points: 10
Default

pouring a 2 inch concerete cap


I want to put in-floor radiant heat tubing 1/2 pexalpex on top of an existing garage floor. My plan is to lay down 1/4" foil bubble insulation on top of existing floor with the tubing on top. I would also drill in rebar anchors on a foot grid and tie horizontal re-bar into those and pour over....Head room prevents more than 2" of new concrete....any problems with this process?

MTgate is offline   Reply With Quote
Old 05-30-2011, 02:47 PM   #2
Too Short? Cut it Again!
 
Join Date: Sep 2009
Posts: 9,635
Rewards Points: 2,000
Default

pouring a 2 inch concerete cap


I would be worried about 2" thick concrete cracking and so forth. Why not float an engineered floor with some flex in this situation?

user1007 is offline   Reply With Quote
Old 05-30-2011, 02:52 PM   #3
Member
 
joed's Avatar
 
Join Date: Mar 2005
Location: Welland, Ontario
Posts: 7,856
Rewards Points: 2,506
Blog Entries: 4
Default

pouring a 2 inch concerete cap


If there is going to be cars on this floor I would be worried about the 2 inch cracking because of the bubble insulation underneath. The insulation couldn't support the weight of a car and would just crush, I would expect.
__________________
Do not PM with questions that can be asked in a forum. I will not respond.
joed is online now   Reply With Quote
Old 05-30-2011, 02:59 PM   #4
Member
 
Join Date: Sep 2008
Location: SoCal
Posts: 1,794
Rewards Points: 1,000
Default

pouring a 2 inch concerete cap


Seems like a lot of work to go to for heating, and yes I would be concerned with cracking.

If there is an exterior wall, why not a PTAC unit mounted in the wall? Or a mini-split unit - a little more money but even easier to install? Both are heat/cool all in one unit.

I have a PTAC in my garage (finished and now used as a hobby room for my wife's sewing/quilting and my ham radio / electronics tinkering). And planning to use a mini-split for a master bedroom addition this summer.
vsheetz is offline   Reply With Quote
Old 05-30-2011, 02:59 PM   #5
Civil Engineer
 
Join Date: Mar 2009
Location: Boston
Posts: 4,252
Rewards Points: 2,082
Default

pouring a 2 inch concerete cap


You cannot successfully install rebar in a concrete floor less than 4 inches thick. The problem is the lack of cover. ACI requires a minimum of 1-1/2 inches clear cover on top of the rebar, and 2 inches clear cover if the concrete touches soil. With a two inch thick slab, this is obviously impossible.

Should you install rebar or wire mesh, the anticipated result will be rusting of the rebar or mesh, with ensuing expansion of the metal, followed by cracking of the concrete.

You can install a 2 inch concrete floor without rebar, you may want to consider using fiber concrete to reduce cracking.

If you plan to continue to use the garage for vehicle storage, you would certainly want to rethink using bubble insulation. As previously noted, this would certainly compress, and possibly break, under normal garage type loading.
Daniel Holzman is offline   Reply With Quote
Old 05-30-2011, 04:04 PM   #6
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Rewards Points: 1,000
Default

pouring a 2 inch concerete cap


On top of all that good advise, bubble wrap is as useless as boobs on a bull. If you don't have lots of insulation under the existing slab, you are going to heat the Earth more than your garage. If you are not going to have vehicles in the garage, or maybe even if you will on occasion, consider an inch of rigid foam, then the plywood that is pre-grooved for PEX, then more plywood over that. Paint the plywood and go to work. Or, like mentioned, just deal with a cold floor and have a different kind of heat source. Wearing felt pack boots or tennies and extra socks is pretty cheap and easy.

jklingel is offline   Reply With Quote
Reply


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
240V 2 pole 1/2 inch GE breakers? Isaac-1 Electrical 12 02-09-2010 11:21 AM
14 inch tank on a 12 inch bowl? jimmybush Plumbing 2 10-02-2009 01:13 PM
1 1/2 inch zone valve - can't find BOUTYM HVAC 2 11-20-2008 10:03 AM
Water Heater 1/2 inch pipes tke402 Plumbing 7 10-04-2008 11:19 AM
new 41/4 inch tile does not match old 41/4 inch tile sweet123 Flooring 2 12-27-2007 08:53 PM




Top of Page | View New Posts

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