# Forum Home Renovation Demolition  Acrow Props + Knocking out a structural wall

## deltoid

I'm knocking out a structural wall under my house and wondering about the placement of acrow props. (I will be getting a restumping company in to install stumps in place of the wall however they suggested I remove the wall myself and save some money). 
In the attached image the red dots/lines indicate where the new stumps will go. I know the image looks a bit wonky but that is because I merged 2 photos together.  
The blue dots indicate where I plan on using the Acrow Props. The blue cross is where I plan on putting an Acrow prop once I have removed that section of the wall (if I can physically put the prop there as I may not be able to get a level base for it). 
My questions are:
1) Are the positions I suggested for the props correct or overkill? 
2) How do I use the props (I know they extend and lock in place but I mean should I be putting a solid piece of timber under them to disperse the weight? Should they be secured to the beams I am supporting somehow?)
3) Do you have any other advice for me?

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## Haveago1

When you say its a structural wall, is that because it is supporting the beams under which you are placing the acrow props or is there load on the masonary wall between where the props are intended to go?  
If there is a load on the wall between the props, how is that to be supported as I cannot see you have provided for that.....the only load being supported by the props is that currently being carried by the two beams, nothing else.

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## kombiman

Hey Deltoid, 
It looks like the block pillar on the left is holding that bearer and the wall is following it along the wall. 
Dependant on how the joins on the bearers coming in from the foreground in the photos I would put one prop just to the side of the block pillar, knock it out and work along and put one on the other side. Then keep  knocking out until the next one coming in from foreground and repeat.  4 props.  Leaves room to put the stump in as how you have it the props are where the stumps are. 
Out of interest how much for the two stumps? 
kombiman  :2thumbsup:  
check out the pics to know what I mean  http://www.renovateforum.com/showthread.php?t=73559

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## Bloss

I am a little confused. Why wouldn't you simply place new posts (steel or timber) with suitable bracket at the top and flange at the bottom, fix it to the beams with at east two M10 through bolts at the top and into the concrete using say 4 x 10 x 100mm ankascrews for each post into the slab? Hard to tell from a single picture and you should not simply take my suggestion without a professional onsite inspection, but it seem unnecessary to do a two stage process when one should do it. Once the two new posts are in place (I wouldn't call them stumps!) then you can remove the wall. 
Another concern I have would be that bearer/beam/ joist that is sitting on top of the wall and how well and in what way it is attached to the ends of the beams you are putting new supports under. You would want to make sure that it cannot drop or move out as you start demolishing the wall - and it could fail catastrophically with dangerous results at worst and costly ones at best (or might be well fixed and not an issue - can't tell from the photo). 
And am I missing something or do the joist meet at a mitre with no support under the joints? If that is so it is bizarre construction. But I have had a long day so maybe I am having an old-timer's moment!

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## deltoid

Well I've discussed it with my finacee and we decided to just let the restumpers remove the wall. They are charging $220 to do it so after taking into account the cost of hiring the jacks I'd only be saving around $180 doing it myself however if I screw it up and damage the house I'm not insured. 
kombiman, it is costing me $440 per stump and $220 to knock out the wall. These guys weren't the cheapest to quote me but they were the best when it came to returning phone calls, turning up on time, and keeping me informed. 
 I'm also replacing 2 concrete stumps on the other side of the house that have blown out and replacing 2 wooden stumps with steel posts under the house (currently have half of the plasterboard off in the inside house so thought it was the best time to fix the stumps to minimise damage to the internals).

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## Bloss

yep - sounds like the best is to get others to do it. Good luck with it all.

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## kombiman

For $220 I would happily pour them a beer after they did it.  :Biggrin:

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