Replies

1. 
   DanH | Jan 20, 2010 11:06pm | #1

   Just a general hint: You don't need nearly as powerful a jack as you may think, unless you're jacking masonry. Screw jacks will do nicely in most cases, and they have the advantage of being much safer from suddenly slipping. (It does help, though, to have one hydraulic jack, to use for quick adjustments, etc.)

   However, always (even with a screw jack) install cribbing to prevent a major fall should a jack lose it's footing or some such.

2. 
   davidmeiland | Jan 20, 2010 11:08pm | #2

   You want screw jacks. Here is an example of a currently available item, and it's about the size you probably want:

   http://www.amazon.com/Jet-Equipment-Tools-440320-Screw/dp/B00018A1J6

   For the most part these types of jacks range from 5 ton (1" dia. screw) up to 25 ton (2-1/2" dia. screw). I have a large collection of them, mostly 2x8, 2x10, and 2x12 sizes (the second number is the length of the screw) and they are seriously useful and powerful when you are under a house trying to lift it. Also have a few 4" and 6" sizes, which are useful if there isn't much clearance.

   There are tons of jacks on eBay, mostly older but still perfectly good. That's where I found most of mine. Here's a cool old Simplex:

   http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=360225449483&ssPageName=STRK:MEWAX:IT

   The trick with eBay buys is to find stuff that is close by, otherwise the shipping gets stupid.

   It goes without saying that structural lifting is extremely dangerous, and you need to know exactly what you are doing.

1. 
   zombies_kill | Jan 21, 2010 12:20am | #3

   Awesome answer, thanks a ton. Does anyone have a clue what stores actually sell these? Shipping has to be a killer.

1. 
   DanH | Jan 21, 2010 07:38am | #9

   I looked up and saw that Northern Hydraulics has them here, starting around $35 a throw. And some other outfit was similar. Certainly used would be cheaper, and the things are indestructible, so long as the screws don't get bent and they don't get rusted tight.

   You can get away with a few jacks, shifting them around and cribbing under the other areas, but that's really slow, tedious, and more dangerous. In any event you'd need 4-6 minimum, and 20 wouldn't be too many for a house that size.

   [Though, if, as you say, you're only "leveling up" the house and not lifting it overall, you can probably get away with fewer.]

   Also start looking around for a large supply of cribbing. If you find someone with the used jacks they likely have the cribbing too.

2. 
   zombies_kill | Jan 21, 2010 12:23am | #4

   Oh, and what exactly does the ton rating mean? I assume that is the max load it can easily lift or something, and not the max it can safely hold, correct?

3. 
   TomT226 | Jan 21, 2010 06:06am | #5

   I like these. You can usually find'em used or even to rent.

   http://www.ellisok.com/ellisok/products_screwjacks.html

1. 
   Mlandry | Jan 21, 2010 06:39am | #6

   I know someone who has a bunch of screw jacks for sale in Ma.

   Let me know if you are interested.

   Mike

1. 
   zombies_kill | Jan 21, 2010 04:12pm | #13

   Email me- John at [email protected] with some details

2. 
   benbuilder123 | Aug 16, 2013 08:05pm | #15

   I know this is an old post, but if the screw jacks are still avalable, please send me an email at [email protected]

3. 
   benbuilder123 | Aug 16, 2013 08:06pm | #16

   I know this is an old post, but if the screw jacks are still avalable, please send me an email at [email protected]

4. 
   junkhound | Jan 21, 2010 07:15am | #7

   2 or 3 cheap HF hydraulic jacks and a bunch of 1x, 2x, 4x and 6x blocks or concete blocks to stick in place to hold position.

1. 
   DanH | Jan 21, 2010 07:36am | #8

   Concrete blocks are dangerous to use since they can crush suddenly and unexpectedly. If you do use them at all, be sure that you always lay them with the holes on the top and bottom, not the sides.

5. 
   zombies_kill | Jan 21, 2010 11:06am | #10

   The second number of the jack size (2x10 or whatever) is the extension capability, but what does the first number mean?

   Is there any downside to getting a 20 ton jack as opposed to a 10 ton? I don't mind paying a few dollars more for the extra power. Say I'm jacking up the same place. Will a 20 ton jack be easier to raise than a 10 ton?

   So no one knows anywhere around Hartford CT where I can get some? I don't need a specific store, maybe a chain of stores that carrys them. Do building supply warehouses carry them normally?

1. 
   davidmeiland | Jan 21, 2010 11:21am | #11

   The first number is the screw diameter. See my post above.

   The bigger jacks are heavier to move around and they make it easier to raise a heavy load. I don't know what sort of job you're trying to do. Last jacking job I did (still underway, actually, I need to go get my jacks out of there) involved raising part of a house that had settled. The perimeter was fine... great foundation, no settling there... but the interior piers were poured on topsoil and the girders under the house had settled badly. Over time (20 years), the entire house had become distorted, with the ridge beam settling, the walls moving out of plumb, etc. The jacking force required to correct that type of thing far exceeds the actual weight of the building, because you are trying to move all of the wood-to-wood connections in the building back to their original positions, as well as lifting the dead weight. I have approximately 20 jacks under the house and most of them are 20 ton. I do own a few smaller jacks for shoring ceiling and whatnot but they're not much fun when you really need to crank. I don't know if I could break one but I'm not really into finding out. Big jacks are your friend if the load is heavy.

   Most expensive way to go is to buy new. The Ellis products are good, there are cheap screw jacks at Harbor Freight, easiest way to get old ones is eBay and craiglist, but it doesn't happen overnight. Of course you can rent jacks at any rental place, and if you don't expect to do this again, just rent...

   Here's part of the crawl space in question. There are about 15 concrete piers IIRC, and 1-2 jacks per pier (always two at beam splices).

   
1. 
   TomT226 | Jan 21, 2010 02:38pm | #12

   Man, now that's what I call a
   Man, now that's what I call a quality crawl space. Can't see any snakes, spiders, roaches, possums or coons. Even a 'lectric light.

   Where's the TV?

1. 
   davidmeiland | Jan 21, 2010 08:19pm | #14

   That's the view from the bar.
   That's the view from the bar. The pool is over to the right, the dance floor past that.

6. 
   IdahoDon | Aug 16, 2013 10:07pm | #17

   http://www.ellisok.com/ellisok/searchres.html

   These are dirt cheap - why someone would buy anything else is beyond me!!!!