Browse Forums Paving & Concreting Re: Voids under house foundation - how to address? 3Feb 13, 2023 9:25 am Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Voids under house foundation - how to address? 5Feb 13, 2023 10:17 am Quickly Re1. You will need to determine the footing type, depth width, reinforcement Size.. might wish to consider a scan? Re3. The newer slabs are Polystyrene/voids designed to float and flex? Older rafts have grid thickenings, they should try to line them up with masonry walls Re.4 Contour/slope causes water to flow down. do you have drain channels, swales diverting the runoff stormwater away? Re5 the crack show the consequences not the cause, you'll need to address the cause first, search underpinning, just a thought the perimeter footings may need to go deeper, remedy might take a while Also start mapping the data, otherwise you'll never know if things are improving? Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Voids under house foundation - how to address? 6Feb 13, 2023 10:28 am StructuralBIMGuy Quickly Re1. You will need to determine the footing type, depth width, reinforcement Size.. might wish to consider a scan? Re3. The newer slabs are Polystyrene/voids designed to float and flex? Older rafts have grid thickenings, they should try to line them up with masonry walls Re.4 Contour/slope causes water to flow down. do you have drain channels, swales diverting the runoff stormwater away? Re5 the crack show the consequences not the cause, you'll need to adress them first, search underpinning, just a thought the perimeter footings may need to go deeper Appreciate your effort as i'm sure you're busy. RE 1. Yes, this is getting beyond the info I can rattle off with accuracy As mentioned it's ~1982 built. I know it has steel reo grids in it, can see a very small part of this in sections - and also hit this a bunch of times when drilling the holes for the sub-slab termite treatment. Width and length is easy enough, thickness is harder to say. RE3. Understood - highly doubt it's the former, defintely the older style - which I suspect was a poor choice given the highly reactive clay soil here but assume thats just how things were done then. RE4. On atleast 2 sides the water runs away naturally to some degree - my focus had been limiting the water getting there in the first place - hence focus on the gutters which were major issue. Re5. Understood and agree.Am aware of underpinning and will look into again but think this is a tad beyond the anticipated scale of the issue. Atleast I'd certainly hopeso as limited info on that indicates its very expensive - that aside what is needed, is needed. Apreciate your replies and info. Re: Voids under house foundation - how to address? 7Feb 13, 2023 11:17 am RE1 You can't keep drilling the slab unless you have engineering drawings. That's why scanning has become popular get an engineer not an inspector with a new tool? (humour) RE3 deep edge raft beam with grid thickenings is far superior. I've inspected many houses 50year and older hardly any cracking. RE4 It could be gutters, below ground cracks, etc a case of elimination and monitoring RE5 You'll need to check as how far down you need to go.. unfortunately no silver bullet fix If you need to go deeper, maybe beam , offset piles. Make sure the advice giver is a qualified engineer Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Yeah my reasoning is just that those house posts are designed for vertical load not lateral. I just didnt want to risk interfering with the existing house… 4 11728 you need to make an application to your local council for this as they are the approval authority for driveways cheers Simeon 1 7247 Interesting. You have great clearance to damp proof course all the way around which is rare with so many cowboy landscapers and concreters. Is there sufficient fall… 2 2996 |