Re – Compliance to Design Guardian Issued NCR No. xxx-001 & 002
Our Ref: xxx
Date: xxx
To
xxx Contracting Company LLC
P. O. Box xxx, Dubai, U.A.E.
Attention : Mr. xxx, Senior Project Manager
Project : xxx Tower, Dubai – U.A.E.
Subject : Re – Compliance to Design Guardian Issued NCR No. DG-AR-NCR-001 & 002
References : a) xxx dated 15 December xxx
b) xxx dated 14 January xxx
c) xxx dated 14 January xxx
Dear Sir,
We are writing in response to your letter ref: xxx dated 07 April xxx concerning two NCRs issued from Design Guardian and we would like to respond as follows:
- xxx: Bathroom Pods – all floors – uneven floor tiles and tile edge lipping. Irregular grout color to floor and wall tiles.
M/s xxx (Contractor Name) response – Uneven floor tiles & tile edge lipping.
We again reiterate that the lipping is a direct consequence of cupping/bending in the tiles procured and supplied by the Main Contractor.
Tiles are a Free Issue Material selected, procured and delivered to M/s xxx (Contractor Name) by the Main Contractor.
The concerns over the quality of the tiles received by M/s xxx (Contractor Name) especially in terms of flatness and dimensional tolerance & color variations were raised to the Main Contractor in multiple quality reports (appendix A).
We have also already notified the Main Contractor that the varying differences in bends and undulations can even be observed in these tiles when selected from a same box.
We further remind the Main Contractor that his own tile supplier has executed a mockup wall at the start of the project which has demonstrated very clearly for all parties that lipping is unavoidable using the available tile tolerances and the staggered design of floor tiles is highlighting more the undulations and lippage.
M/s xxx (Contractor Name) is delivering the best product quality possible based on the quality of tile materials delivered by the Main Contractor and no amount of workmanship can rectify bends and dimensional variances in the tiles.
M/s xxx (Contractor Name) took all possible measures to ensure that tile lipping remains as close as possible to the tolerance allowed by the project specification and international standards.
However, we will not accept under any circumstance to be made responsible for any consequence resulting from the Main Contractor’s selection of tiles.
M/s xxx (Contractor Name) response – Irregular grout color
We refer to our letter ref (k) and we reiterate again that the grout color is only occurring when in contact with the tiles type TL-202.
The light grey grout was tested on various types of tiles including the feature wall tile and tiles used in different projects and it was observed that no variation when in contact with feature wall tiles or other tiles except TL-202.
Test boards were also provided to the Main Contractor proving the same (appendix B).
Also the manufacturer M/s Master Builder Solution has visited the site on several occasions and M/s xxx (Contractor Name) factory and checked all the possible conditions & reasons leading for such color change. The manufacturer has involved a laboratory who has concluded that the major cause of grout color variation is the irregular levels of applied tiles generating different light reflection and creating a visual illusion of color difference (appendix C).
In the end, the root cause of lipping and grout color variation is without any doubt the irregularity and dimensional tolerances of the Free Issue Tiles TL-202 selected, procured and supplied to M/s xxx (Contractor Name) by the Main Contractor and have no relation with M/s xxx (Contractor Name) workmanship, materials or application.
Therefore, the closure of this NCR is the liability of the Main Contractor and If you need our support to close the NCR in any discussion with the Engineer or the Employer, we will be glad to assist, but besides that, no arrangement, action or coordination for this matter is required from M/s xxx (Contractor Name).
Also as we stated during the meeting on 07 April xxx, during final snagging works, if specific locations are found to have extreme lippage from tile pieces, M/s xxx (Contractor Name) will replace these specific tiles to reduce the impact of this observation, provided that the Main Contractor supplies suitable replacement tiles and selects the replacement tile piece to be used.
Furthermore, we have applied a grout solution in Level 1 pods that darkened the shade of grout and hidden the color reflection and irregular absorption caused by the tiles defects. If such solution is found acceptable, then the same can be applied on all the remaining pods after approving its associated costs by the Main Contractor.
- DG-AR-NCR-002 (Bathroom Pods – Inconsistent Vanity and Cistern counter pencil edge finish – all floors)
All the sets in all levels were produced with pencil edge 1 mm consistent as per the approved drawings. However, following the Engineer’s change instructions as comments on WIRs to have a washbasin and cistern chamfer edge, we have made the relevant alterations in the pods in levels 1, 2, 3, 19 & 20 and changed the edge from pencil to chamfer consistent in each pod.
Once level 1 pods marble chamfering is approved, we will continue with the same touchup for the rest of pods in upper floors.
Conclusion
M/s xxx (Contractor Name) are under no circumstances responsible for any consequences arising from quality of free issue materials.
Additionally we request your quality engineer to inspect all the remaining pods in our factory and approve prior delivering to site.
We also remind you that M/s xxx (Contractor Name) is an off‐site manufacturer which produces pods in factory, delivers completed units to site, then raises and secures approval for each pod upon delivery of pods to site and prior to installation.
While M/s xxx (Contractor Name) will address any snags which are raised at final stage and during handing over in accordance with the terms of our Subcontract, we will not accept any rejection especially when such rejection relates to tiles, or any other Free Issue Material supplied by the Main Contractor or to damages on site for pods due to MEP or your other subcontractors work inside and around the pods.
M/s xxx (Contractor Name) will not be responsible for any delay in the completion of deliveries of pods or any consequences resulting from lack of availability of approved Free Issue tile material from the Main Contractor.
We further reserve our right to claim for an extension of time equal to the same number of days by which the delivery of the Main Contractor’s material is delayed.
Yours faithfully,
On behalf of M/s xxx (Contractor Name) LLC
xxx
Projects Manager