Dry Partition Walls Variation and further explanation.
Date: xxx
Ref: xxx
Kind Attn :Mr. xxx
Project :2B + G + 14 + Lower Roof Hotel Building on Plot No. xxx at Al Barsha
1st, Dubai U.A.E.
Sub: Your letter reference AP/269/CC/249 Dt: 16-02-2017 for “Dry Partition Walls Variation” and further explanation.
Our design was submitted by GYPSEMNA based on authority request as per tender drawing (pg-2), project specification in minimum required dB (pg-5) as well as acoustic study provided (pg-6) by your office (letter reference no. AP/269/CC/114 – pg- 6-8) .
- From two pre -qualified companies, one is Gyproc and other is Gypsemna, we also received the proposal from Gyproc that was designed exactly as per tender drawing and required value of dB and there is margin for tolerance i,e. 7dB (international standard) .
Whereas Gypsemna proposed their system exactly as per our specifications with reference no. CC/AP/269/MAT/CIV/110 Dt: 17-09-2016 and you commented approved as noted i.e. within the authority requirement and tolerance value ( first approved submission pg no. 51, 52 with field test report carried out by Drywall Technical Consultants (pg-54,55). There is no authority requirement mentioned in any of our approved document( bldg. permit –pg 20 issued without any partition drawing).
- As per the specifications the partition design should be E90 and classification of rating E413 and field test should in E996 as per pg no.14 and as per ASTM E336 pg no 12 note no.03 the design value cannot be reached in field test due to presence of flanking ( pg-14).
- We submitted the shop drawings for mockup room on 2-11-2016 and toilet drawing on 05-11-2016, both are commented. The toilet drawing was commented as per meeting held on 10-12-2016 because in the intended document the toilet partition dB 55 cannot be achieved in specified wall thickness, so contractor being instructed to reduce the acoustic value for designed wall thickness(100 mm).
- Contractor submitted the revised drawing on 14-11-2016 (pg-62-64) based on the meeting held on 07-11-2016 along with a comparative sheet . This revision was the wet area acoustic rating reduced for 55 to 52 as per the meeting conclusion by adding the resilient channel with other wall area also to maintain wall thickness as per tender drawing.
The contractor also mentioned (pg no 65-67) “Detail of wall partition from specification/shop drawings proposal- 1 and revision plan”, which is self explanatory between project requirement, previous submission and last submission under heading new submission and changes instructed in last meeting and the new proposal by Gypsemna prepared on 30-11-2016 (pg 68-81)
Consultant commented on 20-11-2016 based on our letter ref CC/AP/179/16 Dt: 14.11.16 on our submittal to retain the toilet wall dB 55 instead of 39 (pg-82-95)
- Contractor intimated on 30-11-2016 (pg-96) to Arkiplan indicating the concern to finalize the partition issue which is being delayed due to various discussion/meetings and intimated in item no 7 that if partition drawing will not be finalized there would be further delay.
- In reply of our letter ref CC/AP/197/16 dt: 30-11-2016 Arkiplan reply to submit the details of shop drawing for the acceptance without highlighting the concerned and meantime in item no.03 consultant stated “However mock up partitions can be started without any further delay to avoid further effect on project completion”(pg 100).
- Even after the 03-12-2016 letter the multiple discussions were going on between client and acoustic consultant as well as Gypsemna Engineer , the meeting held in City Max Office on 14-12-2016, The Gypsemna was represented by Mr. Abeer Alkhirat for submission of the revised proposal( discussion for authority approval and acoustic consultant requirement)
- The contractor intimated on 20-12-2016 with letter ref CC/AP/216/16 and attachment of the minutes of meetings are self explanatory, updated the status (pg 102-104) and consultant returned the contractor submittal on 15-12-2016 by stating contractor letter ref:CC/AP/216/16 and stated Not Approved without any other comment (pg-105).
- The contractor attached the proposal of the Knauf and Gyproc for your reference regarding acoustic value where the Knauf designed very high than the project requirement with more wall thickness (pg-106-119) and Gyproc designed almost the same as per the project requirement. (pg-120-128) as well as the Gypsemna revised submittal prepared on 20-12-2016 (pg 134-136) to address the consultant comment on wall P08 & P08A (variation work).
- The consultant commented on our submittal CC/AP/217/16 on 02-01-2017 through letter AP/269CC/207 (pg-137-140) where consultant also explained for the partition variation at P-08A.
- Arkiplan forwarded contractor’s letter dt: 29-12-2016 by highlighting contractor letter the issues related to mock up room requirement including contractor intimated about drawing released by ID and incorporating changes in the mock up room shop drawing at partition wall (pg- 141-147) including document transmittal Dt 28-12-206 ref: AP/269CC/36.
- On 15-01-2017 the contractor intimated that the client has approved the final drawings and dB’s on 12-01-2017 (the meeting held at site 08-01-2017 with Mr.Girish of Arkiplan, Mr.John of Citymax, Mr.Ramlal for Chirag and Ms.Aveera from Gyproc. In that meeting decided that the contractor should submit 55dB for room partition and final drawing was submitted accordingly. The client given the approval to go ahead with 55 dB verbally to start and contractor attached the entire scenario including intimation of the variation).
In the same communication item no. 04 is self explanatory and contractor attached the document related variation and original scope of work after approval of our shop drawing with comment (pg-159) in the documents from pg-148 to 166 ( the same letter is reattached for clarity).
- Contractor intimated on 25-01-2017 under the heading “ Regarding our reply of minutes held at citymax office dated 05-01-2017and request for the extension of time till 31-08-2017 and approve the variation” as well as intimation of the further delay and the chronological major event attached (pg 167-169).
- On 13-02-2017 contractor re-intimated for partition wall variation for time and cost both by attaching the chronological events in summarized form under the heading ”ACCOUSTIC VALUE AND CONTRACTOR’S DOCUMENT FROM TENDER SPECIFICATION, DM AND ID” from serial no 01-15 (pg 178).
Contractor also attached “DETAILS OF COMMUNICATION IN CHRONOLOGICAL ORDER FOR ALL THE EVENTS FOR GYPSUM PARTITION WORK IN TYPICAL FLOOR” (pg 179-183) in item no. 01 -15 having explanation for the communication form 26-06-2016 to 15-01-2017.
Regards,
For xxx Contracting L.L.C.
xxx
Project Manager