Browse Forums General Discussion Re: Advice on holes under slab, cracks etc. Please! 22Jan 12, 2011 12:37 pm Melly This problem is a reflection on poor site compaction and one of the problems with waffle pod slabs. A: You home is on fill, of part of it. So this is a question mark, I would not build on fill or a slopping block. B: Check to see if the holes (voids) are in the areas of plumbing pipes. As you said it was sinking around the house, my bet this is the storm water pipe are, not compacted after it was layed, so a bit of rain and it sinks down a bit. so do the pipes under the slab. Localized subsidance. C: The grade around the slab should deflect water from going under the slab. D: You must fill these holes (voids) to support the footings and stop more water from going under the slab. E: This is common with waffle pods, people just dont see it. F: Inspection. If you want it inspected get a structual engineer, not cheap charlie. You may spend 1000. G: Is it a problem? A defect is only a defect when it becomes one, not if it has the potential to be one.( looking at it from a legal angle.) Well, Yes and no. The slab should show some cracking in the areas of the voids, but, this may take years. If you notice cracking in your floor tiles you have a problem. Some movment of the house is normal at 8 months (more so on cheaper sorry to say it but poor built homes) but it may not be related to the slab. If the brick work shows cracks, as they are over the footing you know you have slab movment. H: Was it a spec home, why did they sell it at only 8 months old. I: What to do if it is not as per the engineers plan. Sorry, You will have a long road all up hill to get them to fix it. J: What I would do. If its bugging you, get it inspected dont forget theres a grand to start with. Did out the areas around the voids and get as much concrette as you can under the footings (remember acting on you own accord may let them off the hook if it goes bad latter). Make sure that water can run away from the slab. Thats all that you can do with this problem. I did not look at your photos as connection is to slow. Yours are only small holes in comparison to what I have seen. K: Mell it is very unlikly that your home will fall into a big hole, so dont worry to much. Cracks can be filled in plaster and from what Ive see over the past 3 years I have not seen a house that is 100% perfect but they still seem to remain standing. Some say most slabs are over engineered anyway ( I dont really agree) but its all down to cost. Doing a proper job takes more time and therefor money. I hope this has been a help to you, as I know what you are expirencing. Get it looked at, get it repaired and enjoy your home and dont worry about what may happen in 5 years time. All the best to you and let us all know what the out come was. Cheers KW............... “It's just as unpleasant to get more than you bargain for as to get less” George Bernard Shaw. The CSIRO BTF18 explains differnt types of cracks and what "normal" is Google this and the top result is actually the latest version. You normally have to buy this from… 9 9319 it depends on the natural ground level, if they excavated their boundary wall needed to be built as a retaining wall. If you filled, which sounds like the case then you… 1 7084 I know foam has been around since the 90's and CSR started manufacturing Hebel in 1989, so it's definitely possible 5 5437 |