17-1010 v3.0/The Living House/XPS Insulation for Rammed Earth Walls - A Follow Up


Since we were advised on our last question that we could not proceed with using XPS that contains HFRs in the rammed earth walls we have since found that DOW produces a XPS product called Xnergy that does not contain HFRs. We were therefore looking to use this XPS in the walls of the Living House project. 

However the importer of the Xnergy has since advised us that they only have 40mm XPS board in stock in NZ. The void between the rammed earth walls that we are trying to fill is 100mm, and we cannot make it any smaller or larger for structural engineering reasons, and it can also only be filled with rigid insulation otherwise the walls cannot be rammed properly. Apparently minimum order quantities apply as the product is shipped in from overseas, and our project does not require enough to meet a container load order. 

We have however been approached by another XPS importer who happens to have some 50mm XPS board (that is manufactured using the HFRs) in NZ at present that they cannot sell (as noone appears to want that particular size, 30mm and 40mm being the only sizes that are used normally in NZ). They were therefore going to bin this product.

Given that we would almost literally be salvaging this board from the rubbish bin would it be acceptable to use this particular XPS, even though it was made using HFRs, in place of the compliant XPS since the compliant XPS would have to be shipped into the country for us, while the non-compliant product is already in the country and is heading for the waste stream. 


Because the Red List material in this salvaged product is not a primary ingredient (not needed for this use, but incidental in the available source), this product is allowed.Technically the available material is not "salvaged" because it has not been used, but given the remote location, small quantity and specialized sizing, and that it is a direct diversion from the waste stream, it is acceptable in this case. See the Salvaged Materials clarification on page 12 of the May 2017 v3.1 Materials Petal Handbook for more information on salvaged materials and Red List compliance.

Post ID 6734

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