Bathroom Tanking & Waterproofing: What You Actually Need

Tiles and grout are not waterproof. Read that again. Every year Irish homeowners rip out mouldy plasterboard and rotten floors because a shower was tiled straight onto bare board. Tanking - a continuous waterproof membrane under the tiles - is what keeps water where it belongs.

Where tanking is essential

• Shower enclosures: full height, plus 300mm beyond the enclosure
• Wet rooms: entire floor and walls to at least 1m
• Around baths with showers: splash zones full height
• Utility rooms and floors over timber - anywhere leaks would be catastrophic

The system

1. Prime

Dust and absorbent surfaces kill adhesion. Prime plasterboard, screed or plaster and let it dry fully.

2. Seal the details first

Corners, wall-floor junctions and pipe penetrations fail first. Bed sealing tape into the wet tanking compound at every junction before coating the flat areas.

3. Tank the surfaces

Apply two coats of tanking compound. The SOPRO tanking system 5kg covers a typical shower enclosure; for a full wet room go for the 20kg kit. Two coats, applied in opposite directions, no missed spots - this is not the place to economise.

4. Tile with a flexible adhesive

Tanked surfaces move slightly, so use a flexible C2-class adhesive. SOPRO highly elastic tile adhesive bonds to the membrane and handles underfloor heating. Use white under light stone or glass mosaics.

How much do I need?

Area	Tanking	Sealing tape	Adhesive
Shower enclosure (~6 m²)	5kg kit	10 lm	2 bags
Standard bathroom (~12 m²)	5kg + details	15 lm	3-4 bags
Wet room (~20 m²)	20kg kit	25 lm	6 bags

The golden rules

• Tanking is cheap; ripping out a mouldy bathroom is not
• Two thin coats always beat one thick one
• Never pierce the membrane - plan fixings before you tank
• Let each coat dry per the datasheet before the next step

Everything above ships from our waterproofing range - in stock in Ballincollig, delivered nationwide in up to 7 working days. Not sure what your job needs? WhatsApp us a photo and we will spec it for you: 021 487 6963.