Design Navigator Message Board

Hi Dom, Thanks for the great feedback. Really appreciate it. If I understand your question correctly you are asking if you place say R-1.39 EPS under any type/size of slab, whether you could simply say that your total slab R-value is R-1.3 (the minimum value from the replacement table) + R-1.39 (you...

Hi, Thanks a lot for letting me know. Thanks also for the detailed description of the problem. That will help a lot to fix the problems. It seems these are issues in Internet Explorer. It all works fine in Firefox. I have now reverted back to the previous version and things should be back to normal....

Hi Corey, Sorry, it took it bit longer to get these into the system. I've added all the three 200DHS beams. I hope that covers your case now. If something is still missing, please just let me know. Is 1200mm the most common distance? If so, I could also add the other DHS options. Best regards Albrecht

Hi horay1, The suspended ceiling scenario is simple. The steel rafters don't add any significant R-value, but they also don't bridge the insultion. So they don't reduce the insulation R-value. You can simply use the DesNav calculator as shown below. http://design-navigator.co.nz/phpBB3/D...

Hi Genesis, That's a very good question. 1. Most of the heat loss from a slab floor goes through the slab edges. The smaller the slab area, the more edges there are in relation to the slab area. Therefore the R-value of small slab floors can be quite low. You could have a look at http://www....

No need to comply with the BPI if the design complies with the Schedule or Calculation Method. Both of these are "Acceptable Solutions" meaning that the BCA has to accept either of them. Garages are usually excluded from the thermal envelope (in any of the compliance methods). So they can ...

Hi Alex, Yes, you are right. Gaps are simply still air gaps. Like you say cases where the insulation does not fill the whole cavity. Reflective gaps are gaps where one or both sides are reflective. In practice that is usually the aluminium backed paper. In NZ it is un-usual to put that into walls, b...

Hi guzzihead, I don't have personal experience with this but believe it is a very good concept. Very good insulation and good thermal mass. No infiltration, no obvious moisture issues. I think there is a Christchurch or Dunedin company doing a similar thing here in NZ, but I had a look on the web an...

Hi Paul, I think your calculations look about right. That's the sort of R-values I would expect. But - and that's a big BUT!!! - I would feel quite uncomfortable to have rigid insulation hard up against framing or sheathing. The red weathertightness fags go up in front of my eyes. If any water would...

Hi guzzihead, Seems you are doing everything right. Very good insulation, good window type and size, good orientation. So you are certainly on the right track. Now to answer your questions: I don't think there will be too much thermal mass if you have concrete in the main floor. I say this because y...