RFI.docx

RFI #2 Columbia Basin Roof

1. Looking at the specifications, they call for R-12 for 2". That is no longer correct. There are new testing methods for Polyiso that are now less than before. 2" iso only receives an LTTR value of 11.4 not the 12 they call in the spec.The drawings call for one layer of 4" and one layer of 2" for a total R37.Based on the new Rvalues this would only achieve R35. In addition 4" insulation is not stable and not recommend. This also conflicts with the specifications that calls out any layer greater than 2.7" should be multiple layers AGREED. CORRECTIONS HAVE BEEN MADE TO DWGS AND SPECS - SEE REV1 DOCUMENTS

2. The specifications call to fully adhered the insulation and then the next paragraph indicates to mechanically attach. Section 3.3 D&E. Insulation should be mechanically fastened. See Rev1 specs.

3. Cover board Section G 1& 2. One says to mechanically fasten and the other says adhere? Cover board should be mechanically fastened. See REv1 specs.

4. Is the roof deck concrete or metal? The south end of the roof has a steel deck and the north end of the roof has a wood deck.

5. Section 3.4 C indicates to loose lay sheathing paper.? This cannot be done unless laid under the insulation and only if the insulation is mechanically attached? They are calling for it over the cover board. The requirement for sheathing paper has been removed from the requirements. See Rev1 Specs