Popular: Sikaflex · waterproofing · grout · data sheets
For new basements, or where the soil can be dug away, stop water on the face that the soil and groundwater press against. Build watertight concrete, seal every joint, coat or sheet the outside face, then backfill carefully.
General guidance based on the manufacturer data sheets. Site conditions differ: confirm the system with MCT before you start. Where we do not name a product, ask us and we will confirm the right one.
Confirm the groundwater level, soil report, drainage and joint layout with the structural engineer. Decide where the construction joints and expansion joints go before any concrete is poured.
Add a crystalline waterproofing admixture, about 1000 g per 100 kg of cement (SikaControl-760 p.1, p.2), or a liquid waterproofing admixture (Sika-1 PK p.1). Cure properly, especially in hot, windy weather (SikaControl-760 p.2).
SikaControl®-760 should be used in all structural concrete that is constantly or intermittently in contact with water such as sea walls, tunnels, basements, structural and precast concrete. SikaControl®-760 can also be used as crystalline waterproofing admixture for cement mortars and plasters. T… (TDS p.1)
Sika®-1 PK is used for waterproofing of mortars and concrete, in particular for: Renders, masonry mortars and screeds, Reinforced and unreinforced concrete, Brick, concrete and stone substrates, Indoor and outdoor applications, such as basements, swimming pools, tunnels, water tanks, manholes, cu… (TDS p.1)
Cast a PVC waterbar into the centre of construction joints (Sika Waterbar V-20 L SH p.1, p.2). Alternatively, use a swelling sealant or profile at the centre of the wall with at least 8 cm cover in reinforced concrete (SikaSwell S-2 p.2) or a swelling profile for water pressure up to 2 bar (SikaSwell P Profiles p.3). Fit the same around pipe sleeves.
Sika Waterbar® V-20 L SH is used to waterproof construction joints in concrete structures such as those in water retaining structures, including reservoirs, canals, sewage plants, dams, swimming pools etc. (TDS p.1)
Joint sealing: Construction joints, Pipe and steel work penetrations through walls and floor slabs, Around all types of penetrations and construction joints, Construction joints in cable ducts, etc. Fixing / Adhering swellable profiles:, SikaSwell® A Profiles, SikaSwell® P Profiles. (TDS p.1)
To seal: Construction joints, Pipe and steel work penetrations through walls and floor slabs, Construction joints in precast concrete, Construction joints in tunnel segments, Construction joints in cable ducts, etc, Around all types of penetrations through concrete. (TDS p.1)
Cast an expansion-joint waterbar into the centre of the section (Sika Waterbar O-20 SH p.1, p.2). For joints with settlement or remedial sealing, use the bonded tape system laid in epoxy adhesive (Sikadur-Combiflex SG-20 P p.1, p.3), which is for experienced professionals (Sikadur-31 DW p.1).
Sika Waterbar® O-20 SH are used to waterproof expansion joints in concrete structures such as those in water retaining structures, including reservoirs, canals, sewage plants, dams, swimming pools etc. (TDS p.1)
Sikadur-Combiflex® SG-20 P is used for sealing: Movement joints, Construction joints, Pipe penetrations, Cracks, Building components where differential settlement is expected Sikadur-Combiflex® SG-20 P is used for the following areas:, Tunnels. (TDS p.1)
Structural adhesive for bonding: Concrete elements, Hard natural stone, Ceramics, fibre cement, Mortar, Bricks, Masonry, Steel, Iron, Aluminium, Wood. (TDS p.1)
Fill tie holes and blowholes, and remove laitance. Then apply a rubberised bitumen tanking membrane in 2–3 coats on a damp but not waterlogged face (Sika Igasol Emulsion BA-10 p.1, p.2), or a cement-based slurry in at least 2 coats (SikaTop-107 Seal PK p.1, p.2). Where the soil is aggressive, add a solvent-based bitumen coat (Sika Bitumen p.1).
Sika® Igasol® Emulsion BA-10 is used for: Tanking and waterproofing of substructures to provide an impervious membrane, Vapour barrier of cladded walls, Maintenance of many roof types including asphaltfelt roofs, concrete, cement, lightweight screeds, timber etc, As an adhesive for bonding insula… (TDS p.1)
For external and internal waterproofing, on concrete, mortar, brickwork, and steel in: Basements, Swimming pools, Water tanks, Flat roofs, Balconies, terraces, Bridges. (TDS p.1)
To protect concrete surfaces against attack of aggressive soils & subsequent backfills; such as : Retaining walls, Basements, Columns, Foundations. (TDS p.1)
For large basements, a glass-fibre reinforced sheet membrane against groundwater can be used (Sikaplan WT 1200-16 C p.1). It must be installed by Sika-trained contractors only (Sikaplan WT 1200-16 C p.3).
Waterproofing of basements and cut-and-cover structures against groundwater (TDS p.1)
Let the coating dry fully before backfilling. Backfill in layers so stones do not tear the coating. Ask us about protection boards.
A starting point for a site proposal. Quantities, prices and the final specification follow a site visit or photos.
| Step | Product | Pack | Source |
|---|---|---|---|
| 2. Make the concrete watertight | SikaControl-760 | SikaControl®-760 is available in 5 Kg & 25 kg pack. | TDS p.1 · March 2025, Version 04.01 |
| 2. Make the concrete watertight | Sika-1 PK | 05 ltr jerry can 20 ltr plastic can 200 ltr drum 1000 ltr IBC Bulk supply in tanker is… | TDS p.1 · August 2026, Version 02.02 |
| 3. Seal construction joints and penetrations | Sika Waterbar V-20 L SH | — | TDS p.1 · May 2021, Version 01.01 |
| 3. Seal construction joints and penetrations | SikaSwell S-2 | 600 ml unipacs | TDS p.1 · May 2021, Version 02.01 |
| 3. Seal construction joints and penetrations | SikaSwell P Profiles | — | TDS p.1 · May 2021, Version 01.01 |
| 4. Seal expansion joints | Sika Waterbar O-20 SH | 15 m rolls | TDS p.1 · May 2021, Version 02.01 |
| 4. Seal expansion joints | Sikadur-Combiflex SG-20 P | — | TDS p.1 · May 2025, Version 04.01 |
| 4. Seal expansion joints | Sikadur-31 DW (professionals) | — | TDS p.1 · May 2021, Version 03.01 |
| 5. Coat the outside face | Sika Igasol Emulsion BA-10 | — | TDS p.1 · May 2021, Version 01.01 |
| 5. Coat the outside face | SikaTop-107 Seal PK | — | TDS p.1 · May 2026, Version 03.02 |
| 5. Coat the outside face | Sika Bitumen | 14 Kg pails | TDS p.1 · May 2021, Version 01.01 |
| 6. Sheet membrane for larger projects | Sikaplan WT 1200-16 C | — | TDS p.1 · May 2021, Version 02.01 |
It makes the concrete itself highly resistant to water (SikaControl-760 p.1), but joints and penetrations still need waterbars or swelling seals (Sika Waterbar V-20 L SH p.1; SikaSwell S-2 p.1).
Both are listed for basements. The rubberised bitumen goes on damp surfaces and resists aggressive soils and contaminated groundwater (Sika Igasol Emulsion BA-10 p.1, p.2). The cement slurry bonds well to sound concrete and is also used for retaining walls (SikaTop-107 Seal PK p.1). The choice depends on site conditions: ask us.
No. SikaSwell S-2 and SikaSwell P Profiles are not for movement joints (SikaSwell S-2 p.2; SikaSwell P Profiles p.3). Use an expansion-joint waterbar (Sika Waterbar O-20 SH p.1).
Ask us: it depends on site conditions. Sheet systems on file must be installed by Sika-trained contractors (Sikaplan WT 1200-16 C p.3), and SikaProof A-08 is not for hot climates (SikaProof A-08 p.3).
Steps and product facts are taken from the manufacturer data sheets (page cited). Products are named only where the data sheet confirms the use; quantities follow a site visit or photos. General guidance: check the data sheet or ask us before you start.