Waterproofing of terrace slab of overhead tank, lift head room of Laboratory Animal Facility and telephone exchange in service block of CRI at ACTREC

Amount

Surface Preparation: All loose and de-bonded concrete/ screed /APP membrane , loose particles, dirt & should be removed. Roof substrate must be pressure-washed with water with, a minimum working pressure of 1,400 psi is to be used to and/or remove all dirt, dust, chalking and waste products. Remove algae, mold by using bleach solution or biowash.

Crack Repair: All visible hairline cracks on concrete roof screed more than 0.50 mm and not giving hollow sound, should be cut and widen in V shape with mechanical cutter in the size (10mm W x 6mm D). Fill cracks with Dr. Fixit PU sealant / Hybrid Sealant with suitable gun and smoothed with a putty knife or trowel. Allow sealant to cure a minimum (72 Hrs.) 3 days.

Screed Repair: Remove loose and damaged concrete roof screed in pockets with mechanical cutter. Clean the concrete screed with high pressure water jet to remove dirt and loose particles. Brush apply a bond coat of Dr. Fixit Pidicrete URP mix in the ratio of 1:1 (URP 1: Cement 1) by volume to make it lump free slurry when applied on in the pre wet surface. Laid to fall roof screed in correct slope and gradient. Mix Dr. Fixit Pidicrete URP 10% by weight of cement in (M20) concrete in ratio of 1:1.5:3 i.e., one bag of 50kg cements: 1.5 times volume of sand: 3 times volume of aggregates: 25L water. Level the repair mortar and finish with trowel. Moist cure should be done for 7days. Air cure screed for 7days, before application of roof top coat coating system.

Rainwater outlets treatment: Hacking and chipping the surface around the rainwater drain outlet up to 25mm in depth. Apply bond coat of Dr. Fixit Pidicrete URP in the ratio of 1:1 (URP 1: Cement 1) by volume over the corners and pipe insert outlet gaps. Filling the gaps around drain mouth with (PMM) polymer modified mortar mixed with Dr. Fixit Pidicrete URP 10% by weight of cement in the ratio of 1:3. Providing & fixing 100 mm width 45gsm glass fiber mesh all around the periphery of drain mouth of rainwater outlet sandwiched with Dr. Fixit Roofseal Classic. Apply the second coat of Dr. Fixit Roofseal Classic with an interval if 5-6 hours all over the rainwater outlet.

Vertical upstand: Providing 100mm x 100 mm Square / rectangle upstand of M20 grade concrete or with PMM around mechanical equipment like HVAC, air-conditioning, solar panels. Etc. Apply a self-priming coat of Dr. Fixit Roofseal Classic and two coats reinforced with 45 Gsm glass fiber mesh without dilution in the interval of 4 -6 hrs. Apply Dr. Fixit PU Sealant at around the junction of fabricated stand inserted and wall mounting mechanical fixtures.

Waterproofing: Apply a coat of Dr. Fixit Roofseal Classic (diluted with water in the ratio 2:1) as Self Priming 9.0 – 10.0 Sq.mt / liter in the SSD condition. Allow coating to dry for 3-4 hours. Apply two coats of Dr. Fixit Roofseal Classic @ 2.0 - 2.2 Sq.mt / liter / coat, without water dilution, the rate of application being the same for both the coats. This would ensure correct consumption of material that will deliver a total DFT of 450– 500 microns. Allow the system to air cure for 5 days minimum. Check to see no void surface is left untreated / uncoated. The material having following technical Specification as per ASTM D 6083 M – Type II, Attains a Tensile Strength of 2.5 N/mm2 confirming to ASTM D 2370; Elongation at break ≥ 300% confirming ASTM D 2370, Adhesion to Concrete 2.0 N/mm2 confirming ASTM D 4541 and Crack bridging ability up to 2 mm, Air cure the coating for 7 days, before water pound test for 48 hrs. The system comes with 10 years waterproofing warranty from M/S Pidilite Industries. For vertical surfaces: Apply a 2 coat of Dr. Fixit Roofseal Classic with forced coverage of 3.3 - 3.7 Sq.mt / liter / Coat. The entire terrace should be coated with Roofseal Classic along with parapet walls needs to be enveloped with Roofseal Classic / Raincoat system. Note – Coating should be terminated below the drip mould on the vertical surface.

Surface preparation Break & remove the existing waterproofing layer and reach upto RCC slab level followed by cleaning and preparation of surface with the help of wire brush and hand grinder. Remove all loose concrete, dust with air blower. Undulation in RCC slab surface, honeycombs, pin hones, imperfections should be chiselled to the sound substrate and repair with Polymer Modified Mortar a dual shrinkage compensated Dr. Fixit Polymer Modified Mortar HB. Moisture cure for 5 days then allow drying out slowly. PVC pipes to be placed / inserted in the core cut areas, apply a coat of Dr. Fixit Pidicrete Epoxy bonding agent over this, sprinkling fine sand / quartz sand and fill the gap with Dr. Fixit Micro Concreate or with shrinkage compensating Dr. Fixit Polymer modified mortar HB.

Roughen and clean the junction of wall and floor with wire brush and air blower to remove the dust particles. Moisten the surface with water & apply a bond coat of Dr. Fixit Pidicrete URP and cement (1:1) by volume with brush. Providing & Laying angle fillet (gola) of size 50 x 50 mm in width over the bond coat when it’s in wet condition. Preparing PMM by taking 1 kg Dr. Fixit Pidicrete URP, 5 kg fresh cement, and 15 kg graded quartz sand. (i.e., in the ratio of 1:5:15) on RCC surface (slab and wall junction) finishing in smooth finish. Including moisture cure for 5 days then allow drying out slowly. etc complete.

Crack Repair: Cut and widen all cracks more than 1mm up to 8mm in width and depth in V shape with mechanical cutter. Clean the cracks with air blower. Apply a coat of Dr. Fixit Pidiprime A primer over prepared crack in the length, allow the surface to cure tack free upto 20 mins. Fill the crack with Dr. Fixit PU sealant with suitable gun and level the sealant with spatula / putty knife. Allow sealant to cure a minimum 72 hours. Providing and laying minimum 100mm width 60 GSM non-woven geo textile fleece over the length of shrinkage crack in sandwich layer of a bond coat of Dr. Fixit Cipoxy 16D epoxy primer and two topcoats of Dr. Fixit Flexi PU 270 (I). Apply the second coat after an interval of 12 hours.

Waterproof Coating: Provide and apply moisture insensitive Dr. Fixit Cipoxy 16D primer @ 0.20- 0.25 kg/ m2. Allow the primer to cure for 6 – 8 Hrs to tacky condition. Provide and apply 2 coats of Dr. Fixit Flexi PU 270 (I), a single component PU based cold applied seamless waterproofing membrane over the above PUF Layer, coverage at the rate 2.3 - 2.5 kg/m2 in 2-3 coats to achieve DFT of 1.5 mm. The PU membrane shall be terminated 300mm above FFL, self-curing for 5 days. The Waterproofing material shall have Solids > 85%, Tensile strength > 2 Mpa as per ASTM D 412, Elongation > 400% as per ASTM C 1305, crack bridging up to 2mm, Shore A Hardness > 70 as per ASTM D 2240, Adhesion to concrete > 2Mpa as per ASTM D 903, Water vapor permeability > 14gm / m2 / day as per ISO 9932:91, Puncture Resistance > 300 N as per, ASTM E154- 2013 Water Head Resistance 50M as per DIN 1048.

Separation Layer: Providing & Laying 200 GSM Geotextile (non-woven polyester) membrane with a min of 100mm wide overlap loosely laid over Dr. Fixit Flexi PU 270(I) membrane, etc., complete.

Horizontal Protection - Mortar screed for protection & Slope: Providing & laying of average 100 mm thick protective screed of M20 grade by keeping minimum 50mm thickness at drainage point with slope 1:100 containing 12 mm, 100% virgin polypropylene fibers @ 0.9 Kg/Cu.m with a broom finish, well compacted, curing for 7 days etc. complete. The screed shall be raised to the wall in the form of vatta to achieve a smooth corner. The screed shall be divided into panels of 4 mtr X 4 mtr with 6 mm wide x 10 mm deep construction joint and filling the same with Dr. Fixit PU sealant, confirms to ASTM C-920-S, NS, 25 & BS EN ISO—11600: 2003 Type F & G as per manufacturer specification, etc, complete.

Bombay Construction (BID ID -3192670)