SPL REPAIR TO BLDG NO P-50 OF OTM ACCN OF 5 RAJPUT UNDER GE (SOUTH) DELHI CANTT-10

M&L for complete removal of existing treatment on wall/roof projections including facia, cornices etc by scrapping with mechancical sander(having mechanical vacuum mechanism) having RPM not less than 1500, sanding pad of 80 grit having dia of 7"/9" to make free from dust, loose paint etc by skilled labour complete all as specified and directed.

M&L for water proof cement based putty @1kg (undiluted) per sqm of average thickness 2mm over the plastered /old prepared painted surface of wall and sanding of the putty surface with mechanical wall sander (having mechanical vacuum mecghanism) having RPM not less than 1500, sanding pad of 240 grit or above to make the surface . Step 1: Mix the putty powder by adding water as manufacturer's instruction and mix it with putty mixer with the mixing capacity of min 2.5 kg putty per minute. Step 2: Apply the first coat of the prepared mixer with the help of fully automatic airless spray machine/manully of putty application finishing the surface even and smooth in level without any undulations. Step 3: Allow 6-8 hrs time to dry the putty surface.

M&L for one coat of acrylic water based exterior grade primer @ 0.9litre(undiluted)/ 10 sqm diluted with water in 1:1 ratio to be applied with fully automatic airless spray machine and allow 6-8 hours to dry the surface for painting of subsequent coats complete all as specified and directed.

(i) Preparation of concrete surfaces by wire brush and cleaned top surfaces of cement concrete.

(ii) PCC type B-0, 1:2:4 (12.5mm gradded aggregate) to maintain slop as in roof padding alongwith liquid water proffing compound.

(iii) Rendering 15mm thick in CM 1:3 on concrete surfaces on roof, Chajja, parapet, shunkan, etc.

(iv) Supply only liquid water proofing compound, complete all as specified and directed by engineer-in-charge.

(v) M & L single component solvent based moisture cured polyurethane resin based low viscous highly penetrative primer to be mixed properly with electric mixture and to be applied by brush/roller over the entire surface. The deposition of primer should be minimum 200 ml/sqm, however the same can be varied based upon surface porosity.

(vi) M & L two coats of single component non-UV resistant based polyurethane to be applied over the primed surface in an interval of 4–6 hrs. The topcoats should be applied with brush/roller. No dilution is required for these two coats. A non-woven geotextile sheet of 60 GSM to be sandwiched between the layers. The deposition of PU should be 1.80 kg/Sqm providing avg thickness of 1.20 mm. The tensile strength of the product should be minimum 1.80 N/mm². The elongation of the free film should be minimum 650% as per ASTM D412, shore A hardness should be minimum 45 as per ASTM D-2240, Crack Bridging @ -9°C minimum 1.50 as per ASTM C 836 / C-836, Solid Content should not be less than 90%. Moreover, the material should confirm to ASTM C-836, ASTM C-898.