Can the building stay in use while you work?

Yes. We work in sections, and each section is finished the day it is started.

What happens to low spots that pond?

They are topped up with CHEMGROUT 215 non-shrink grout and sand before the membrane goes on.

Is the new membrane left exposed?

No. It is covered with the SEALOPOL 3P protection sheet, and DURACOTE HB goes on where the roof stays exposed.

How is the finished roof tested?

It is flooded and held for 24 hours.

All systems, by building zone

Re-waterproofing.

Roofs that have failed, on buildings that cannot stop. Most of our repair work is this: overlaying a live roof without stripping it, in sections, between the rain. This page sets out the layers, the order of work and the test we carry out before we leave.

2Coats of MONOLITHIC MEMBRANE 6130K, applied hot, with FLEX FLASH F fabric between them.

300 mmThe least the system turns up every wall and upstand.

24Hours the roof stays flooded for the pond test.

The build-up.

Four layers, starting with the roof that is already there.

As numbered on the drawing

Existing waterproofingSurveyed, blisters cut out, surface conditioned. Low spots that pond are topped up with CHEMGROUT 215 and sand.
MONOLITHIC MEMBRANE 6130KHot-applied rubberised asphalt, seamless over the old system. Two coats, with FLEX FLASH F fabric between them.
SEALOPOL 3P protection sheetMineral-surfaced bituminous membrane, torch-sealed at the edges.
DURACOTE HB, two coatsPolyurethane coating where the roof stays exposed.

The re-waterproofing build-up drawn exploded: the existing slab and old membrane, then the new hot-applied membrane, SEALOPOL 3P and the DURACOTE coating

How the job runs.

We survey the roofThe existing waterproofing is checked and blisters are cut out. Anything that needs correcting is reported before work starts.
Ponding areas are levelledLow spots are topped up with a mix of CHEMGROUT 215 non-shrink grout and sand.
Surface conditionerCHEMCOAT SB over the roof, 300 mm up the walls and 50 mm into every pipe sleeve. It must dry fully, usually in 30 to 60 minutes, before any membrane goes on.
The roof is marked into sectionsEach day's area is set out as a grid, so every section is finished the day it is started.
MONOLITHIC MEMBRANE 6130K, with fabricThe first coat is spread hot with a squeegee. FLEX FLASH F fabric is broomed into it while it is warm, and the second coat goes over the fabric the same day.
SEALOPOL 3PLaid over the membrane on the flat and 300 mm up the walls.
Then we pond testThe roof is flooded and held for 24 hours.
DURACOTE HBTwo coats, where the roof stays exposed.

Walls, pipes and the melter.

Walls and upstands
The membrane and the protection sheet turn up 300 mm on every vertical surface.
Pipes
The surface conditioner is taken 50 mm into every pipe sleeve.
Fabric laps
FLEX FLASH F is lapped 50 to 75 mm, and every lap is set in membrane.
Thin areas
Where the membrane is found thin, more is applied hot over it and the two fuse into one coating.
The melter
The membrane is heated on site in a double-jacketed melter. Where it has to stand on the roof, we agree its position with the main contractor first, because of its weight.

Materials.

MONOLITHIC MEMBRANE 6130K
Hot-applied rubberised asphalt membrane, laid as one seamless coating. It is always covered, never left exposed or trafficked.
CHEMCOAT SB
Quick-drying solvent-based bitumen primer, the surface conditioner.
FLEX FLASH F
Spun-bonded polyester reinforcement fabric.
SEALOPOL 3P
Polymer-modified bituminous sheet membrane, surfaced with mineral slates.
CHEMGROUT 215
Cementitious non-shrink grout, mixed with sand to level ponding areas.
DURACOTE HB
Polyurethane coating, in two coats.

These products are made by CHEMIND. Where a project specifies another manufacturer's system, we apply that instead.

Repairs in our register.

Thirteen entries in our job register name a repair, a rectification, a re-roofing or a re-waterproofing in the title, from 1987 to 2022. Five of them:

1987
Re-roofing of the existing roofs at levels 5 to 9, Komtar, Penang
1989
Re-roofing of the INTAN building, Jalan Ilmu, Petaling Jaya
2008
Leak repairs, Prime Minister's Office, Putrajaya
2010
Re-waterproofing of the administration building roof, Measat Global, Cyberjaya
2014
Re-waterproofing at Taman Abadi Indah, Kuala Lumpur

Most entries record the job as a waterproofing package without naming the zone. See the full register.

Questions we are asked.

Can the building stay in use while you work?: Yes. We work in sections, and each section is finished the day it is started.
What happens to low spots that pond?: They are topped up with CHEMGROUT 215 non-shrink grout and sand before the membrane goes on.
Is the new membrane left exposed?: No. It is covered with the SEALOPOL 3P protection sheet, and DURACOTE HB goes on where the roof stays exposed.
How is the finished roof tested?: It is flooded and held for 24 hours.

Talk to us about a leaking roof.

Phone and WhatsApp016-332 7534

Emailinfo@hydrocon.com.my