Large beam lifting for self build

[leesrubberroom]

We're doing a self build which is actually a conversion of a current industrial building. It has a large flat roof which is supported by 3 x 11m long i-beams, approx 450mm x 300mm section, and they need to be raised by a few feet up to a height of around 7.5m. My question is, for a beam this size (i'm still trying to confirm the weight, but i know it's substantial, is a crane out only option, or is there some other solution using a Genie type lift?

 

[bernardgreen]

Depending on the situation it might be possible to raise it a few inches at a time using a jack and blocks at each end. It is not a risk free method but with care it can be sucessful

Use the jack on a temporary patform to lift the beam, then place blocks of timber under the beam. Do the same at the other end of the beam. Lower the jacks so the beam rests on the timber blocks, put blocks under the jacks and raise the beam further, put more blocks under the beam and lower the jacks. Repeat until the beam is at the required height.

It is essential that the beam is securely held at all times to prevent it moving sideways and thus toppling the pile of blocks supporting it. An Acrow supporting the centre of the beam as it is lifted would reduce the risk of it falling off the blocks

The solid secure support is a temporary structure next to what ever the beam is resting on now.

 

[freddiemercurystwin]

Got a photo of where they're to be installed to see access? The weight will be written in your SE's calcs, the beam size will say something like '457x191x89' where 89 is the weight of the beam in kg per metre length.

 

[leesrubberroom]

Thanks for the input. It's a good idea, and we had thought about a similar idea, but the amount we need to go up, is substantial (about 1.6m on one beam, and the temporary support would need to be so sufficient, it's probably cost as much to construct as it would be to hire a crane. If we had a temporary support in line we could use i'd jump at that.

 

[leesrubberroom]

I don't have any calls for these. Because it's existing for supporting the existing roof, no one has asked for the calls for them. I am getting the beams measured this morning though, so once i know the flange thickness the weight should be easy to calculate.

 

[freddiemercurystwin]

No calcs? Who sized the beams then? Is this being done to Building control approval?

 

[leesrubberroom]

Yes, through a 3rd party, not through LABC. To be honest, we're still in the early stages though. Calcs will probably be needed soon, but we're doing several things simultaneously because of the project timeline. We're confident the beams are suitable, so we're trying to plan the best construction method now, whilst building reg drawings and calls are being done by the SE and architect.

 

[freddiemercurystwin]

Then ask the fabricator the serial size he is providing.

 

[wessex101]

I read it as these are existing beams that are just being raised slightly.

You can use multiple genie lifts to take the weight but not sure they will go as high as 7.5m. No doubt other hoists are available. Failing that crane hire might not be all that expensive. Its been a while since I've used one but for half day to lift some very large steel beams it was a lot cheaper than I was expecting.

 

[leesrubberroom]

Sorry, i probably didn't make it clear in my original post. This is a conversion (from a small storage unit to a residential building), so we're using the existing steel i-beams that support the current roof. The issue is the roof needs to be raised by about 1.6m so we need to take the original beams down, build the walls higher, then raise them back up to the new height. Hope this explains it now.

 

[leesrubberroom]

I read it as these are existing beams that are just being raised slightly.

You can use multiple genie lifts to take the weight but not sure they will go as high as 7.5m. No doubt other hoists are available. Failing that crane hire might not be all that expensive. Its been a while since I've used one but for half day to lift some very large steel beams it was a lot cheaper than I was expecting.

Thanks for that. I'm quoting them now, and you're probably right. I thought it was worth a shot though. If we decide to use SIP panels for the roof construction, we may need a crane anyway, as i'm looking at some large panels which are over 100kg a piece, too heavy to be hauling up on to the roof!

 

[leesrubberroom]

Ok, so i've got some the measurements for the beam, it's a lot smaller than we thought. I'm pretty sure it's a JIS spec beam, 350x175x7 x11, which is 63kg per meter, so the each one weighs 725kg. I'll have to shop around but we might be able to get away with 2 or 3 Genie lifts just about if they go that high. If not i have my crane quotes coming in. Thanks for the help everyone.

 

[catlad]

Genie lifts and 11m =700kg steel beams at 7.5m heigh sounds
like a recipe for death use a crane.