It is difficult, if not virtually impossible, for a non-professional to jack up his or her house. For most home renovators out there, this is like preaching to the choir: they have no desire to lift a house. For others, the project looks dead-simple, an easy way to save thousands of dollars.
Because this is a big undertaking, I look at 3 views on the matter: 1.) Mine; 2.) A homeowner who successfully jacked up his own house; and 3.) A contractor who specializes in foundation and crawlspace work.
1. Do It Yourself House-Jacking Is a Risky Prospect
While few of us are interested in jacking up an entire house, complete with cribs, girders, timbers, and everything else you need in order to lift the entire house off the ground, there are a number of foolhardy souls among us who feel the need to jack up a portion of the house in order to insert an extra tier or beam for repairs.
Lifting Power Problems of Jacks?
The issue is not so much lifting power. Your ordinary hydraulic jack is no match for a house. Take your strongest automotive jack from the garage and this jack will crumble under the weight of a house. More precisely, it will never even begin to lift.
Nor is the issues one of jacking timbers, cribbing, microlam, or girders. Nowadays, any ordinary DIY renovator has access to contractor grade suppliers for such items.
Is It a Manpower Problem?
Nor is this an issue of manpower. I have seen two men jack up entire houses.
The interesting thing is that it requires no special technology. In fact, screw jacks are the main motive force behind house jacking. Hydraulic jacks are also used, and you would want at least a 20-ton jack. Because the 40-ton jack is only incrementally more expensive, go ahead and purchase it rather than the 20-ton jack.
Yes, I said "purchase" because your rented hydraulic jack will be underneath the house for a very long time, running up charges.
Difficult to Jack in One Piece
Here's the issue. A house is constructed of thousands of pieces of lumber, nails, screws, wire, metal, masonry, and countless other types of building materials. All of these materials are interlocked, like a jigsaw puzzle. A house does not raise or lower like a giant box. Instead, a house raises or lowers more like a giant King-sized mattress. Imagine going underneath a mattress and trying to lift any portion of it with your fist. Most of the mattress remains stock-still, completely unmoved by your efforts. Even areas of the mattress in the immediate vicinity of your hand barely moves. It is only the portion of the mattress directly above your hands that raises. So it is with a house.
Place one, two, or even five hydraulic or screw jacks in close range beneath the house, lift slowly, and the results are disappointing. First, you hear the house protest with cracks as loud as rifle shots. Joists groan. Upstairs, plaster and drywall crack and crumble and fall. Yet below, there is little sign of elevation.
Moral of the story: if you plan to do any kind of raising and shoring of any portion of your house from beneath in a basement or crawl space, just keep in mind that you will not be able to influence more than a small portion.
Even then, you will probably accomplish nothing more than replacing rotten timbers with new timbers or girders and maintaining the same slant of the floors above.
2. Motivated Homeowner: It Can Be Done
In response to this article, I received an e-mail from a gentleman who-who recounts a story of how he was able to jack up a house by himself. I have cleaned up some of the text, corrected spelling errors, and edited for clarity:
...I have assisted my "professional" parents in building and renovating this original "built from the town dump by the caretaker"- style 1920 farmhouse into a 2,900 sf 5 bedroom/ 3 bathroom / 3 living room with 3 fireplaces lodge.
My professional parents were teachers and they read and worked on this house every summer here in New Hampshire. (-20) and the house has undergone some severe climate changes in 45 years since we've had it. Settling! Dropped 5" in some areas and I'm in the process of realigning and jacking now. Working by myself! ...And I've brought it up 3" since September but broke for winter, just needed to wait till the 7" of ice in the basement melted to start my forms.
...Read, watch, ask, do, and you'll know what to do.
...And that, my friend...is how lifting and supporting a house is done.
3. Contractor: Do Not Do This Under Any Circumstances
I've said elsewhere on this site that when you have foundation problems, you need to look for a contractor that specializes in the foundation, crawlspace, and basement areas. In other words, that whole below grade world. General contractors can work on that area, of course. But why not find someone who deals with this every single day?
Harold Jones of Midlothian, Virginia's All Crawl Contractors weighed in on the matter. He's so comfortable living underground that he even began his message on his phone while in a crawlspace. On his stomach. Now, that's dedication. Harold says:
While anything is possible for a homeowner. In truth, some home repairs are best left to professionals. These include certain things that require extensive training and testing, such as 220 volt electrical, running gas lines, elevators, and HVAC unit repair.
There is also a gray area where additional testing or licensing may not be required, but experience and expertise would be heavily recommended. These include foundation repair, structural repair, moisture control, chimney cleaning, framing, and retaining walls. In most states, a homeowner can do just about all repair work themselves so long as it is not used a rental property. Getting to the matter at hand, structural repair (i.e., joists, floor leveling, beam replacement, pier work) can be dangerous repairs to attempt without the proper tools, let alone knowledge.
I remember when I was on my second or third beam job back in 2005, I set up my cribbing and jacks in what I thought was the correct pattern. When my one jack failed, I found myself under a house on the wrong side of my cribbing, watching the house settle. Lucky for me, I have always stressed safety with my employees and had a backup jack near me and was able to get everything shored up without much worry.
It's not the work that's difficult. It's a matter of understanding home construction, weight distribution, and having more than enough equipment on hand for contingencies. Without these things, you could end up trapped under a collapsed house or worse yet dead.
If you want to put a temporary jack under your house, have at it. If you want the risk of doing a repair incorrectly and having it come back on home inspection, that’s your call. But if you want to risk life and limb to save $800 by replacing a section of beam yourself, make sure your life and health insurance are paid up.