Replies

1. 
   xMikeSmith | Jan 31, 2004 04:29am | #1

   couple things... 1) if most of the basement is below grade and it is completely closed off.. then you will get natural ground heat to help thaw..

   2) close the stairwell and any other openings.. put a space heater in the basement..

   but don't run it hotter than the available oxygen supply.. run it during the day whaen someone is there to observe it..

   turn it off at night and keep the openings closed

   it'll take a couple days.. but it should that from the bottom up and the top down..

   Mike Smith   Rhode Island : Design / Build / Repair / Restore

1. 
   scampernatra | Jan 31, 2004 04:44am | #2

   Mike, we actually tried running a salamander and two small propane heaters for the better part of a day without much success. All the heat seemed to go up to the floor instead of down into the ground. The floor is about five feet below grade. We also have another house, same situation but this one the floor is on grade. Have heard about tenting but have never tried this or seen it done. 

1. 
   UncleDunc | Jan 31, 2004 05:07am | #4

   You're not going to see any success in a day doing it with warm air. It took weeks of cold air to freeze it. It'll take weeks of warm air to thaw it.

   Circulating the warm air down off the ceiling will help, some. Concentrating the warm air with a box, thawing a small area at a time, and then insulating the thawed parts might go faster.

   How deep is it frozen? How much will delaying the slab cost you? That $700/day might start looking like a bargain in a few more weeks.

2. 
   xMikeSmith | Jan 31, 2004 05:21am | #5

   scamp... where are you located?

   if it was last week around here.. i'd say forget it..

    but next week it's supposed to get above freezing and nature will help you out..

    a frozen basement has one he*l of a lot of BTU's  stored in the frost.. you might also try tarping it with several layers of tarps.. so the ground heat can thaw it from below...

    just warm air from a salamander is not going to do it..

    try this... take a long rotary bit and drill down about 2'.. drop a thermometer down the hole.... what is it reading. ?.  around here my guess would be 40 - 45..

   and it goes all the way to china... if you can cover the frozen floor .. that heat will get to work on it from below

   but hey, whadda i no ?

   Mike Smith   Rhode Island : Design / Build / Repair / Restore

   Edited 1/30/2004 9:23:48 PM ET by Mike Smith

1. 
   scampernatra | Jan 31, 2004 06:33am | #7

   I'm in S. W. lower Michigan near the big lake. Our temps have been averaging about 10-20 the last two weeks. Not sure how deep the frost is as there is about a 6" layer of snow over most of the floor and I haven't checked.When we pour isn't real important except how it affects our scheduling.

   We have stairs to put in as well as some short sections of wall and we need a floor to set them on. We are near drywall stage on both houses so we need heat. I can put a furnace in now( prior to concrete) and set it up on blocks pouring around it, after every thing thaws, but I'm afraid that will end up looking cheesy.

1. 
   xMikeSmith | Jan 31, 2004 07:45am | #8

   well, you can hang the short walls from the joists.. and you can hang the stairs from the joists.. and pour your slab under them when it finally thaws..

   either that or beat yourself up trying to push spring...

   either way.. you can tell your kids about walking to school thru 10' drifts ..and the rookie about how the real men uster do thingsMike Smith   Rhode Island : Design / Build / Repair / Restore

2. 
   dmck52 | Feb 02, 2004 07:06am | #9

   Our foundation contractor has a fhw oil furnace/radiant heat tubing/blanket setup that we're using to thaw an 1100sf basement. Should take 5-6 days. With setup/pickup charges, should run about $1/sf to thaw. We did cook off about $300 of propane trying to thaw with space heaters. Kept the upstairs pretty warm, but didn't do much to the frost.

   Doug

3. 
   scampernatra | Feb 03, 2004 06:01am | #10

   Ouch! I may end up either hanging the furnace or putting it up on blocks. At this point I have more time for these projects than I do money.

2. 
   Piffin | Jan 31, 2004 04:51am | #3

   Mike. It depends how cold it is, how deep the frost went, and how drafty the place gets at night. I've seen one take three weeks of heating to intolerable levels to thaw the ground. It's hard top force heat down.

   That's why they invented the electric blankets..

   Welcome to the

   Taunton University of Knowledge

   FHB Campus at Breaktime.

   where

   Excellence is its own reward!

2. 
   bkhy | Jan 31, 2004 06:03am | #6

   tenting is probably cheapest. nail a 2x to the  perimeter walls near the floor,use lath to attach poly,blow temp heat under--leave an exit hole so the air can circulate.  Easy way is to hang the furnace &heat the whole basement---takes longer but no heater rental expense