This is an inspection of a waffle slab that Cornell Engineers completed some time ago and the original video has been on Youtube for quite a while except I’ve done a voice over with a description of some of the things we were looking at during the inspection.
Don’t forget, this was not the inspection required for a Form 16 inspection certificate and we weren’t checking the slab against the drawings – that inspection had already been done by the design engineer’s inspector.
This was an inspection of the waffle slab for the owner’s peace of mind and we were just checking against good practice in the assembly and make up of the waffle slab before it was poured.
So during the inspection we talk about the pods themselves, the ribs that are formed between the waffle pod void formers, the edge beams of the waffle slab, the slab reinforcement, the beam reinforcement, penetrations, cover, (which is the amount of concrete around the reinforcement once it has been poured) and edge reinforcement.
if you’re building with a volume builder and you get a chance to take a video of your slab before it is poured I strongly recommend doing it. A video is better than 1000 pictures and a video like this can help rule out problems with the slab if problems ever arise.
I guess this video will help you know what to take a video of!
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What is the trimmer bar doing structurally under slab mesh?
Is it possible to use waffle to have a slab for a shed raised 1.3m off ground level?
Is it possible to build a two storey home on this kind of waffle pod system? And is it possible to use a cut and fill method on slope sites with a waffle pod system?
These are not great on highly reactive clay are they? Would you have any clue why builders are still using this kind of slab when it's not recommended to build on specific types of land?
Great video. Thank you for explaining this in detail. Just wanted to know more about piers and edge beams. Do these increase waffle pod strengths? What about Concrete strength? Looks like most builders these days use the minimum recommended strength of 20mPa. Do you reckon that a 25 or even a 35 mPa concrete will make a waffle pod function better? What function does the re-entry mesh serve? How about waterproofing and sanding the surface before laying out the pods? What about vapour barriers and damp proofing? Sorry to ask so many questions but with builders cutting corners for maximum profits, I think home owner's only remaining hope is an honest engineer 🙂
Do the water pipes get tested before the pour?
Thanks – I needed an explanation. It appears to be what the builders are using behind us on our friend's sloping clay block. I had my doubts about the strength. Building inspections down here are a thing of the past. Future house prices will be reduced by the lack of quality.
nice video, thanks mate
Great video!