porta cabin jacking up structure and sub framing it

[gaz1]

ive been asked if a porta cabin can be jacked up and sub framed under it
to restraighten the structure and also level the building out as well



the structure is something like this and the jacking legs are at full height but still leans and has sagged about 1,1/2" for what i can see it has 2 i beams running the full length of the porta cabin

with the structure holding on the legs only im thinking that the structure can sit on a built subframe underneath it built level then lowered onto the subframe to relevel the whole portacabin

im asking as my idea could be so crap and im not sure if it could be done or not

but thinking in the lines of 2 posts on either side of it with an I beam welded to the top of posts i presume with angles due to load

the i beams would sit on top of the other I beams of the subframe

5/6 posts of the length with tie ins between each post

 

[Welderpaul]

Is it a job worth bothering about? I'd run away, could be a right bag of ballcocks.

 

[gaz1]

oh id agree thats why i said id ask on the forums first if it could be done or not

using something like this as the subframe below the portacabin



they are trying to put a car trailer under the porta cabin but its already off level and they have lifted it using jacks already

the red lines are the subframe struts im thinking of it spreading the weight there suggestion was using 2 long I beams on either side of the portacabin but even i wouldnt suggest that one

 

[roofman]

i did one once after the legs settled into the ground for years..spent nearly a week and the end result was doors and windows that did,nt open properly again,the whole frame had twisted and everything else had followed. goodluck

 

[Welderpaul]

My experience with them is as long as the 4 legs sit on something level the building will be pretty square and true. As soon as a leg is out of kilter they are so flexible it throws everything out. That might be the first job?

 

[mike os]

as above, get the legs on something solid and you can pretty much level and straighten with them, they are made to sit on the legs, put substantial spacers under the legs if you need more adjustment

 

[pedrobedro]

When I was fork truck driving years ago I lifted a few off the back of lorries delivering them and they were pretty solid. I used to get a decent tip off the drivers as it saved them a lot of jacking a corner at a time to get them down to ground level

 

[bigegg]

I'd run a beam across the end, jack it up a couple of inches.
Lift the legs and pour a concrete pad + brick pillar for the legs to stand on.
Then do the same at the other end.
Borrow a hiab lorry for an hour to lift it, and use postCrete into a sonotube or bottomless bucket might be a faster way?

 

[evobilly666]

The legs are usually 1/4 way in from each end on the average cabin and they use a cantilever to retain strength. There is no real structure to the floor, often just two timber beams. The older the cabin gets the less strength they have and the less they respond to movement. They will flex a lot when moved so usually best to position them, then jack each end till the floor is level, pack them with 100 x 100 shs legs onto concrete pads

 

[gaz1]

thankyou everyone

what i do know the rear left leg has given and is holding nothing been supported by concrete blocks the other 3 are fine however the pins could do with replacing in my eyes but they are holding

so leg holding to the left is not apropiate the right can be done

i used to watch house movers hence the idea in the first place

hence why im thinking of the struts under tha cabin but the I beam underneath taking a good amount of weight and the legs as extra weight takers as the underneath ones are already in the air about 2ft one side and more on the right side

been asked if it could be done but my suggestion is like those house movers way above with i beams underneath could go onto another I beam like that house reference

i can get photos of it tomorrow and whats underneath if that will help matters if it can be done or not im aware already they used jacks under the floor as the leg gave when moving it the second time as im told so put on concrete blocks 3 years ago weve been near the place for last 2.5 years next month

 

[gaz1]

ive had a look at this and its a wood built unit this is how it looks in situe

 

[gaz1]

if i am dealing with this which its a maybe for the moment

it would be 8 concrete pillars built up to get the desired height from here they would be eye beams running under the cabin and another running the full length of the cabin front to back

due to the customer wanting to store a trailer underneath it and the weight of the portacabins extras

something like this

 

[dobbslc]

I'd also price in some extra to account for getting covered in dog sh#t from the hound that's lives in that kennel......

 

[octo0072000]

the whole bit with store car trailer underneath could present problems
if you are pushing under by hand ok, but driving under could be a can of worms
oopps sorry i just knocked the posts and the cabin fell off onto the trailer

 

[gaz1]

its already been mentioned however if thats what the customer is wanting up to them

the red ones are I beams i believe 2 x 4" or 5"for the full length ones to hold portacabin up in blue

below this myself id be considering a little bit more than that personally id be looking at 4 x 12" I beams that would be resting on concrete blocks

the gap before the I beam is for space for such as trailer being off side and gives added room but not by much the drawing below is whats needed for the build

@bigegg whats under yours if you mind me asking?

 

[bigegg]

The new one is on concrete pads under the long rails
My old ones didnt have legs. They were just dropped straight on a 30ft x 30ft x 12in concrete slab which id poured with the intention of building a double garage - before i dropped lucky on the pair of linkunit cabins.

 

[gaz1]

does your rails look like the drawing above with the rails or not bigegg as i have mentioned yours to him depends on what they want to do in my eyes

 

[bigegg]

Yes.
Rails are like that - mine are badly rotted though. Id check what yours are like before putting any weight on them