Clarification Answers.doc

Q 137. Past reports of the lightweight substrate indicate that “the entire roof was wet” and the “top layer of fill was wet as well as the lower section of fill.” In essence, the suitability of the existing lightweight concrete to receive a new membrane system and the manufacturer’s warranty can not be determined until the roof membrane is removed, the light weight concrete exposed, and fastener pull out testing is performed. Prior to the removal of the roof membrane and pullout testing, the condition of the lightweight concrete is unknown and “unforeseen.” If removal and replacement of the light weight concrete is required, how is this additional work to be compensated?

R 137. Past reports mentioned in the question pre-date the installation of one way vents which were installed to dry out the substrate and thus despite the amendment for full roof replacement, GSA does not anticipate a significantly wet substrate, nor has GSA indicated this in the amendment scope. A dry substrate is, however, required for the final IRMA installation. GSA does not dictate means and methods of how to do business to the contracting community; therefore GSA cannot comment on specific methods to achieving an end result of what is specified in the Solicitation document. Proposals shall be submitted to include pricing for all aspects of the Solicitation and information posted on the Federal Business Opportunities website.

***Clarification: All bidders should propose based on the lightweight substrate being dry as prescribed in the RFP documents.

Q 139. After preliminary examination of code requirements for wind uplift that is to be considered in roof design for the IRMA vegetative roof, it has been determined that the amount of weight of soils or ballast (to counteract this uplift) to weigh down the IRMA insulation will exceed the allowable loading of the existing roof. A thorough and lengthy evaluation of the roof structure would be required to determine the extent of the required roof reinforcement. This strengthening will require removal of ceilings, utilities above the ceilings and cause considerable disturbance to the office space below. Since the extent of the reinforcement can not be determined without a complete structural analysis, how is this matter to be addressed?

R139. Section 4.1.1 of the IRMA roof amendment indicates that a full roof survey including full structural loading analysis be performed by the design/builder after award. Information shall be developed at this stage to confirm the loading capacity and shall be addressed in the design.

***Clarification: All bidders should propose based on the roof being able to hold both the IRMA roof and vegetative roof as prescribed in the RFP documents.