Davco K10 Plus is routinely ordered as if it were a cement-based slurry. Here is what the published data sheet actually specifies, and how to check it was applied to it.
Sika publishes the Davco K10 Plus data sheet — the Davco range sits under Sika — and the description it carries is worth reading word by word: a flexible, premixed, ready to use, water based polyurethane Class III waterproofing membrane, designed for use under tile and stone and other resilient finishes. Every clause in that sentence changes how the material is handled on site.
It is supplied in 4 litre and 20 litre pails, in green or grey, and it is applied by thick brush or medium-nap roller. If you arrived here from cementitious waterproofing, this is a different chemistry from the products on that page, and the rest of this guide is mostly about what changes as a result.
The confusion is structural rather than careless. In a Malaysian wet-area quotation the word “waterproofing” usually implies a grey powder mixed on site, because that is what most homeowners have watched a contractor do. So a product with a code, a pail and a wet-area use gets filed mentally under the same heading, and the differences only surface when something on site does not match — there is nothing to mix, the colour is wrong, or the tiler is told to wait a different length of time.
| Cementitious slurry systems | Davco K10 Plus, per the data sheet | |
|---|---|---|
| What arrives | Powder, or a powder plus a liquid polymer to be mixed in a stated ratio | A premixed, ready-to-use liquid in a 4 L or 20 L pail |
| Chemistry | Cement-based, often polymer modified | Water-based polyurethane |
| Mixing on site | Ratio and pot life both matter, and both get abused | None — which removes one failure mode entirely |
| Consumption stated as | Kilograms per square metre per coat | Square metres covered per pail over two coats |
| What is measured | Material consumed per area | Dry film thickness, with a wet film thickness per coat |
| Substrate tolerance | Bonds to sound concrete, render and screed | Data sheet calls for specific primers on lightweight blocks, metal and building boards |
| Waiting before tiling | Depends on the product’s own data sheet | Data sheet states 6 to 8 hours before tiling, and 3 days before flood testing |
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💬 Get Your Instant QuoteNone of that makes one family better than the other — they are specified for overlapping situations and a competent contractor uses both. It does mean that a quotation which names this product but describes a cementitious method has not been thought through, and it is worth one question before anyone starts.
The figures below come from Sika’s published Davco K10 Plus data sheet and product page. That documentation is published for the Australian market, which is where Sika publishes the Davco technical sheets; treat the numbers as the manufacturer’s stated values and ask your supplier for the data sheet edition that applies to the pack actually being delivered to you before you hold anyone to them. Editions are revised, and a figure copied out of a guide is not a specification.
| Item | What the data sheet states | What it means on your job |
|---|---|---|
| Format | Flexible, premixed, ready to use, water based polyurethane membrane | Nothing to mix; nothing to dilute |
| Classification | Class III, described as highly flexible with elongation greater than 500 per cent | Ask which standard that class is measured against for your pack |
| Packs and colour | 4 litre and 20 litre pails; green, or green and grey in the 20 litre | Different-coloured coats make coat count checkable |
| Coverage | About 13.3 m² from a 20 litre pail and about 2.75 m² from a 4 litre pail, at two coats | Turn this into a pail count for your measured area before work starts |
| Coats | Minimum two coats, applied at right angles to each other; further coats if required | Two is the floor, not the target |
| Film thickness | Minimum 1.0 mm total dry film thickness, from a minimum 0.75 mm wet film per coat | The number a stretched job actually fails on |
| Between coats | 1 to 2 hours | Fast, but humidity extends it — it is a minimum, not a schedule |
| Before tiling | 6 to 8 hours | Do not let a tiler start on the same morning as the second coat |
| Before flood testing | 3 days | A flood test on day one proves nothing and can damage the film |
Sika lists the product as suitable for interior and exterior application on commercial and domestic walls and floors, including wet areas such as showers, bathrooms, terraces, balconies, roofs and walkways, prior to tiling. It also notes that being water based and solvent free makes it suitable for confined areas — a genuinely useful property in a small internal bathroom with no ventilation, where a solvent-borne product is unpleasant and sometimes unworkable.
The phrase that does the limiting work is prior to tiling. This is specified as a concealed membrane under a tile or stone finish, not as an exposed wearing surface. If the intention is to leave a liquid membrane visible and walked on, that is a different specification and a different product class — the trafficable-coating conversation is covered in liquid waterproofing membranes. And as with any membrane, the data sheet describes what the product does; it does not describe your substrate. Falls to the trap, sound screed, a working floor trap and a sensible upstand height are all outside the pail and all decide whether the bathroom leaks. Those are set out in bathroom waterproofing and shower floor leak repair.
The data sheet describes the product as Class III and as highly flexible, with elongation greater than 500 per cent. Both are meaningful, and both are worth one clarifying question rather than being taken as self-explanatory.
A membrane class is a rating against a standard, and which standard applies depends on the market the data sheet was written for. So the question to put to a supplier is: “which standard is that class measured against, and does the pack you are supplying carry the same classification?” That is not pedantry — it is the difference between a specification you can hold someone to and a marketing phrase. If a specification for your project calls for a particular class, the classification has to be evidenced for the actual product supplied, not inferred from a family name.
The elongation figure is similar. High elongation is why a flexible membrane can accommodate movement that a rigid coat would crack over, but elongation is measured on a film at its stated thickness, which is another reason the dry film thickness below is the number that matters most. A membrane applied at half its specified thickness does not deliver half the performance; it delivers a film that fails where it is thinnest, which is always at the detail you cannot see.
This is where a PU membrane parts company most sharply from a cementitious slurry, and it is the step most often skipped because it is invisible and adds a visit. Sika’s data sheet calls for priming on specific substrates: two coats of a porous primer on lightweight blocks, an etching primer on metal surfaces, and a suitable Sika-branded primer on building boards.
Those three cases cover a lot of real Malaysian bathrooms and balconies — lightweight block partition walls, metal upstands and trims, and fibre-cement or building board on a stud wall behind a shower. If your job includes any of them and the quotation has no primer line, ask about it before the pails arrive, because a membrane that has not bonded is a sheet of plastic sitting under your tiles rather than a waterproof layer. Priming also has a second effect on a porous substrate: it reduces how much of the first coat gets sucked in, which is part of why the stated coverage assumes the substrate was prepared as specified.
Whatever the substrate, the underlying condition is the same as for any membrane: sound, clean, dry and free of anything that is already letting go. The wider pattern of what preparation failure looks like a year later is in why waterproofing fails.
The data sheet calls for a 50 mm wide polyethylene or polypropylene tape over cracks and joints subject to movement, and at building board and sheeting joints. That tape is a bond breaker, and understanding what it does is the difference between a detail that survives and one that tears.
A membrane bonded tightly to the substrate on both sides of a moving crack has to absorb all of that movement across the width of the crack itself — effectively zero width, so any movement at all is a very large local strain, and the film tears no matter how elastic it is. Lay a strip of tape over the crack first and the membrane is now unbonded across 50 mm, so the same movement is spread across 50 mm of film instead of across a hairline. That is the entire mechanism, and it is why “we just put an extra coat over the crack” is not the same thing and does not work.
The joints that need it in a normal bathroom are the ones people forget: the junction between a lightweight block wall and the slab, the joints between sheets of building board behind a shower, and any construction joint in the floor. The wall-floor angle itself normally needs a detail too. If a quotation has no line for reinforcement or bond-breaker tape at junctions, it has priced a field coat and left out the places leaks actually start.
The data sheet specifies a minimum of two coats applied at right angles to each other, with further coats if required, using a thick brush or a medium-nap roller. The right-angle rule is not a stylistic preference. Any roller or brush pass leaves a film that is thicker in some lines and thinner in others; laying the second pass across the first means the thin lines of one coat sit under the thick lines of the other, and the combined film is far more even than two passes in the same direction would be. In a membrane whose performance is defined by its thinnest point, evenness is the whole game.
The colour choice helps here. Where the pails come in two colours, applying the two coats in different colours makes the coat count and the coverage visible — any patch where the first colour still shows through is a place the second coat missed. Ask for that if it is available, and ask for photographs of each coat before the next one goes on.
“Minimum two” also deserves emphasis. Two is the floor set by the data sheet, and the sheet allows further coats if required. On a rough or porous substrate, or where the wet film thickness per coat is not being achieved, more coats are how the specified thickness is reached — not fewer, thicker ones.
Sika’s stated figures are a minimum 1.0 mm total dry film thickness, built from a minimum 0.75 mm wet film thickness per coat. Those two numbers together are the most useful thing on the data sheet, because they let you check the work with arithmetic rather than faith.
Start from the coverage: about 13.3 square metres from a 20 litre pail at two coats, and about 2.75 square metres from a 4 litre pail. Measure your area, including the wall upstands, and divide. A shower and floor area that works out at two pails and gets one has not received the specified membrane, whatever the surface looks like when it is dry. Write the pail count into the quotation, and count the empty pails at the end — that single habit catches more thin applications than any inspection.
A wet film thickness gauge is a cheap comb-shaped tool that an applicator dips into the wet coat to read its depth directly, and asking whether one will be used tells you a great deal about how the job will be run. It is standard practice on commercial membrane work and unusual on domestic work, which is precisely why domestic membranes are so often thin.
Three intervals appear on the data sheet, and each is broken for a different reason.
The knock-on effect is scheduling: a membrane installed properly puts three days between the waterproofer and the tiler, and a renovation programme that has not allowed for that will apply pressure at exactly the wrong moment. Agree the sequence before the job starts rather than arguing about it on the day.
| Fault | What happens | What the data sheet asks for |
|---|---|---|
| No primer on lightweight block, metal or building board | The membrane never bonds; it lifts as a sheet under the tiles | Two coats of porous primer on lightweight blocks, etching primer on metal, a suitable primer on building boards |
| Watering down the pail to stretch it | Film too thin to reach 1.0 mm dry, failing first at the details | Premixed and ready to use — there is nothing to dilute |
| Both coats rolled in the same direction | Uneven film with thin lines running through it | Second coat at right angles to the first |
| No bond-breaker tape at moving joints | The membrane tears along the crack it was meant to cover | 50 mm polyethylene or polypropylene tape over cracks and joints subject to movement |
| Tiling the same morning | Membrane damaged under the adhesive where it cannot be inspected | 6 to 8 hours before tiling |
| Flood testing immediately | An unfair test on an immature film, and possible damage to it | 3 days before flood testing |
| Upstands stopped at skirting height | Water tracks behind the membrane at the wall, and the leak looks like a floor failure | Upstands specified as a dimension on the quotation, not “as required” |
Two further guides make comparing quotations easier: how to read a waterproofing quotation and questions to ask a waterproofing contractor.
A concealed membrane is checkable for about a day and invisible for the next twenty years, so every check has to be booked in advance. Ask for a photograph of the prepared and primed substrate before the first coat. Ask for a photograph of the full area after each coat, including the upstands, the floor trap surround, the pipe penetrations and the corner behind the door — the four places leaks actually begin. Count the empty pails against the calculated number and photograph them.
Then insist on the flood test, three days after the last coat, with you present when it is filled and when it is read. Mark the water level, leave it for the agreed period, and read it against the mark rather than against a memory. Check the ceiling below at the same time if there is one. And do not let tiling start before the test simply because the tiler is available — once the tiles are down, a failed membrane costs the tiles as well as the membrane, and that is the whole argument for testing first. The general case is set out in toilet waterproofing without hacking and upstairs bathroom leaks.
The bands below are for the installed system — supply, preparation and application by a contractor — not for a pail on a shelf. Product retail prices move with pack size and dealer and are not quoted here; ask your supplier for the current price of the exact pack (market estimate 2026, indicative Klang Valley):
| Installed system | Market range (2026, Klang Valley) | Notes |
|---|---|---|
| Flexible two-part membrane | RM8 – RM14 per sq ft | flexible membrane systems under tile in a wet area |
| Liquid PU membrane | RM10 – RM18 per sq ft | the liquid-applied polyurethane family this product belongs to |
For a bathroom, the figure most people actually want is the job price. ClickBina re-waterproofs a bathroom at RM1,500 – RM3,500 per bathroom without hacking, or RM4,500 – RM9,000 per bathroom with the tiles off and a new membrane laid — those are our prices, not a market range. Where water is already showing on the ceiling below and the path is unclear, leak detection and assessment is RM300 – RM800 per visit, waived if you proceed with the repair. The breakdown of what drives a bathroom figure up or down is in bathroom waterproofing cost, and the per-square-foot view is in waterproofing cost per square foot.
ClickBina waterproofs bathrooms, balconies and wet areas across Kuala Lumpur and Selangor, and on a membrane job the thing worth paying for is not a brand preference — it is a specification you can check. That means the exact product and pack named on the quotation with its data sheet attached, the primer for each substrate priced as its own line, bond-breaker and reinforcement detailing at the junctions rather than an extra coat over them, upstand heights given as dimensions, photographs of the primed substrate and of every coat, and a flood test after the data sheet’s waiting period with you present when it is read. Where the leak path is unclear we do a paid detection visit at RM300 – RM800 per visit and waive it if you proceed. Browse all of our waterproofing and leak repair services, or send photographs of the bathroom and of any product already bought on WhatsApp for a fixed quote.
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