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gavztheouch's Achievements

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  1. My engineer has specified I give 40mm cover to the rebar top, bottom and sides I noticed my 105mm high chairs are more like 110mm. My isoquick is not 100% flat. I cannot buy high chairs the exact size need to give me the correct cover top and bottom. Some of the mesh is bent which will creat high and low spots. These are just a few reasons why it is practically difficult to achieve 40mm cover without a massive tolerance of say ~20mm I have called and emailed my engineer but I’m worried he is away on holiday as I have had no response. I can’t afford to wait around so I’m thinking about dropping my bottom cover to 30mm as this will be easier to achieve. Top cover will be aiming for 40mm but I know there are some high spots of at least 8mm so that will bring that area down to 30mm before we start thinking about bent rebar and other things. What are the downsides of reducing cover? I can think that at some point it will weaken the bond between the rebar and the concrete if it get too close to the surface. Also water ingress rusting rebar may be more likely but the concrete sits on isoquick which is 200mm above ground level.
  2. @JohnMo how would I calculate how much extra heat loss I would have if I tied my UFH to the lower layers of mesh rather than the upper? i have 250mm eps and 250mm concrete the lower layer will be at 70mm from the bottom and the upper layer will be 170mm from the bottom.
  3. Why does it not matter if sheets or rods are placed next to each other in such a way that the concrete cannot completely encase each rod. Is it because the yield strength of the rod is below the amount of grip the rod has inside the concrete, even if it is not complete encased. The rod will stretch before the concrete loses grip?
  4. @Tom How thick is your slab? Do have any concerns by attaching the UFH to the lower mesh. If the concrete slab is nice and conductive to the heat I guess most of it will move up the way. thanks
  5. rebar mesh is horrible stuff to work with. Did you tie your UFH to the lower layers or did you raise them up and attach to the underside of the upper layers after?
  6. Yes I have flying ends Tom, do you have any pics of your rebar mesh going in?
  7. Yeah I’m worried about the mesh creeping up a bit due to bent sections not nesting nice or the isoquick not being exactly 250mm in places. It’s all the compounding errors that made me decide to put the heating pipes under the top two layers of mesh.
  8. Hi I have 4 layers of rebar in my foundation. Two on bottom with 40 mm cover and two on top with 40mm cover. I searched the internet but cannot find any information as to wether the sheets that sit on top pf each other need to be staggered so the longitudinal and lateral bar are not sitting g directly next to or on top of each other. The reason in my mind is the concrete cannot flow right round the bars if they are right next to each other. The downside of offsetting the sheets is it will make it harder to get both sheets up to the edge of the foundation with the same cover of 40mm.
  9. Isoquick laid, feels like a bit of a milestone. Next is dpm and rebar
  10. Why is one corner so low? Are you going to build it up or cut the rest down?
  11. Mistakingly I have lay down about 100mm of type 3 in areas I can not get with vibrating roller. This is areas with drains etc. If I’m doing this by the book my plate compactor does not go deep enough as it only has say roughly 300kg/m2 I need over 1200kg/m2 to get down 100mm. I found this belle product you can rent which has a small foot print attached to the underside of a normal plate compactor which apparently generates over 1600kg/m2. If this is correct then this would work and would be piece of mind for the £50 or so rental fee. Anyone heard about this belle product https://www.altrad-belle.com/index.php?route=product/product&product_id=5575 some more info on the compactor https://static-content.cromwell.co.uk/pdfs/s/medusa_attachments/bel/bel-262-3610m dual force booklet.pdf
  12. Yes raising the surrounding ground by something like 300mm. It’s going to give some more protection against flooding as well sitting a bit higher. We’ll need to work hard to blend the extra height into the surrounding garden.
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