LBS Spritz and Bonding Mortar
Waterproof bonding coat and R3 repair mortar. The first coat of the LBS three-coat waterproof render system for basements, retaining walls and below-ground structures.
A pre-bagged cementitious mortar with WT waterproofing additives. Applied as a rough spritz coat, it forms a high-adhesion key that bonds the LBS system to concrete and masonry and holds under reverse water pressure. The same bag also serves as a Class R3 concrete repair mortar to EN 1504-3 and as a semi-fluid bedding mortar.
What the spritz coat does for the system
In a three-coat waterproof render the first coat has one job above all others: stay bonded to the substrate when water is pushing from behind it. LBS Spritz and Bonding Mortar is formulated for that condition.
Bonds under reverse water pressure
Adhesion is stable even when water is acting from the substrate side, which is the condition an internally applied tanking system faces in a basement or lift pit. Tested adhesive strength exceeds 1.5 MPa.
Waterproof in its own right
WT additives make the coat itself a barrier, not just a key. Capillary absorption is below 0.15 kg/m²·h½ against a standard limit of 0.5, and the hydrophobic surface film slows water uptake during curing.
Controlled shrinkage
Restrained shrinkage is held at or below 0.05 percent, six times tighter than the EN 1504 limit. This protects the coat from through-cracking, which in a waterproofing layer is the failure that matters.
Class R3 concrete repair
Classified R3 to EN 1504-3 with compressive strength above 30 MPa. Localised repairs to the substrate can be made with the same mortar before the system goes on, with no change of product.
Consistency set by water
Mixed at 21 to 22 percent water it sprays or throws as a spritz. At 17 to 19 percent it holds a thixotropic body for trowel repairs and bedding. One bag covers both uses.
Durable in exposed conditions
Retains adhesion above 1.5 MPa after freeze-thaw cycling in de-icing salts, thermal shock and dry cycling. Carbonation resistance meets the EN 1504-2 requirement, with chloride content below 0.003 percent.
A bonding coat built for tanking work
LBS Spritz and Bonding Mortar is a grey, pre-bagged cementitious mortar with a 3mm maximum grain size and WT waterproofing additives. It is applied in a single coarse layer of 10 to 30mm, by hand or by render pump, to form the first coat of the LBS three-coat waterproof render system.
Left rough, the spritz gives the LBS Render Mortar a mechanical key. Beneath a floor screed the sequence changes: two coats are applied, the second after 4 to 6 hours, to form the waterproofing layer before LBS Screed WT is laid.
With reduced water the mortar becomes a plastic repair and bedding mortar. It can be trowelled smooth or compacted 1.5 to 3 hours after mixing, and carries a Class R3 classification to EN 1504-3 for localised concrete repair.
Where it is used
- Waterproof bonding coat before render on walls, floors and soffits
- Localised concrete repair, Class R3 to EN 1504-3
- Semi-fluid bedding mortar
- Concrete and aerated concrete
- Brick, stone and terracotta
- Existing mortar and cementitious substrates
- Old floor substrates and floors subject to water erosion
- Waterproofing key coats and rough coats
Cementitious substrates must have moderate water absorption: neither excessive nor absent. For other substrate types, contact Licata technical support.
Product information
| Characteristic | LBS performance | Standard requirement |
|---|---|---|
| Compressive strength | >30 MPa | >25 MPa |
| Capillary absorption | <0.15 kg/m²·h½ | <0.5 kg/m²·h½ |
| Chloride ion content | <0.003% | <0.05% |
| Adhesive strength | >1.5 MPa | >1.5 MPa |
| Restrained expansion and shrinkage | ≤0.05% | ≤0.3% |
| Resistance to carbonation | dk ≤45 | dk ≤45 |
| Freeze-thaw with de-icing salt immersion | >1.5 MPa | >1.5 MPa |
| Storm cycles, thermal shock | >1.5 MPa | >1.5 MPa |
| Dry cycles | >1.5 MPa | >1.5 MPa |
Values from the LBS Spritz and Bonding Mortar technical data sheet, determined at 21°C and 65% RH. Higher temperatures shorten working and curing times; below 5°C hydration stops.
Before application
- Clean the substrateRemove anything loose or poorly bonded: old friable layers, dust, rubble. Remove oils, waxes, fats and detergents by thorough cleaning or light abrasion.
- Dampen to saturated surface dryWet the substrate until it is saturated but with no free water on the face. Do not apply onto standing water or where water is actively flowing.
- MixAdd three quarters of the mixing water (4.25 to 4.75 litres per 25kg bag) to a clean container, add the powder and mix for 3 minutes with a low-speed mixer. Add the remaining water gradually until the paste is homogeneous. Mix whole bags only.
Applying the coat
- Apply as a rough spritzThrow or pump the mortar onto the substrate in a single coarse layer of 10 to 30mm, covering the whole surface without excessive build-ups. Leave it rough. Do not trowel it smooth.
- Walls: one coatA single coat is sufficient as the key for LBS Render Mortar.
- Floors under Screed WT: two coatsWhere the spritz forms the waterproofing layer beneath LBS Screed WT, apply a second coat after roughly 4 to 6 hours.
- Repair or bedding useMix with 2 to 3 percent less water (17 to 19 percent) for a thixotropic consistency. Trowel smooth or compact 1.5 to 3 hours after mixing.
- Protect while curingShield from wind, direct sun and rain for 48 to 72 hours. Wash tools with water while the mortar is fresh.
Complete the system
Specifying LBS on a waterproofing project?
Licata technical support can advise on build-up, detailing and BS 8102 design. Stock is held at all six UK branches.