BioDry ProSil – Multi-Functional Siloxane Damp Proof Course Fluid (5L & 25L)

The BioDry ProSil is a professional-grade concentrated siloxane injection fluid designed for the installation of chemical damp proof courses (DPCs) in masonry walls affected by rising damp. When diluted with water, it forms a high-performance aqueous solution that delivers the penetration and effectiveness typically associated with solvent-based systems while maintaining the advantages of a water-based formulation.

Using advanced multi-functional siloxane technology, BioDry ProSil cross-links within the masonry after application, lining pores and capillaries to create a highly effective barrier against rising damp. Its true solution in water allows for deep penetration into masonry substrates, ensuring long-lasting damp-proofing performance.

Key Features & Benefits

• Water-based with solvent-level performance – combines safety with deep penetration
• Advanced siloxane technology – forms a durable waterproof barrier
• Deep masonry penetration – true solution in water for maximum effectiveness
• Fast curing formula – prevents dissipation within masonry
• Low alkalinity – safer handling and improved working conditions
• Non-corrosive to equipment – suitable for professional injection pumps
• Odourless and non-flammable – safer for indoor use
• Non-staining and non-salting – clean and reliable application
• Diluted solution stable for 6 months – ideal for larger treatment projects
• Outperforms siliconates and micro-emulsions – professional-grade damp proofing performance

Typical Applications

• Chemical damp proof course installation
• Rising damp treatment in masonry walls
• Pressure injection DPC systems
• Residential damp-proofing projects
• Commercial remedial damp treatments
• Solid and cavity wall masonry systems

How It Works

BioDry ProSil penetrates deeply into masonry through drilled injection holes, where the siloxane technology chemically bonds within the pore structure of the substrate.

This creates a water-repellent barrier inside the masonry capillaries, preventing moisture from rising while still allowing the wall to breathe naturally.

Preparation Before Treatment

External Preparation

• Remove damaged or porous external plinths
• Cut back render above the proposed DPC line
• Lower external ground levels where possible
• Protect paths, plants, and glazing from spills

Internal Preparation

• Remove skirting boards and timber fixing grounds
• Strip plaster to at least 1 metre high or 300mm above visible damp/salt contamination
• Rake out mortar joints to 10–15mm depth
• Brush away dust to improve replastering adhesion

Application Instructions

Drilling Pattern

• Drill holes 10–14mm diameter at slight downward angles
• Hole spacing should not exceed 170mm centres
• Injection line should be minimum 150mm above external ground level
• Drill to approximately two-thirds wall depth
• Treat cavity wall leaves separately

Injection Process

• Inject using low pressure between 5–50 psi
• Continue injection until fluid becomes visible in mortar beds
• In heavily saturated walls, consider drilling two rows of holes
• Seal holes after treatment using strong cement mortar or plastic plugs

Mixing Instructions

Always add BioDry ProSil to water, never water to product.

• Dilute 1 part BioDry ProSil with 4 parts clean water
• 5 litres of concentrate produces 25 litres of ready-to-use solution
• Clean injection equipment thoroughly before and after use

Coverage Guide

Coverage will vary depending on masonry type and thickness; however, a useful guide is:

• Approx. 2.5 litres of fluid per linear metre of 230mm (9") wall thickness

Post-Treatment Replastering & Drying

All replastering should be carried out in accordance with the Biokil Crown replastering specification.

Decorations should be considered temporary for 9–12 months following treatment. During this period, use breathable non-vinyl emulsion paints only. Avoid vinyl paints and woodchip wallpaper until walls are fully dried.

Good airflow and ventilation should be maintained around treated walls throughout the drying period.

Technical Information

Feature	Specification
Product Type	Multi-Functional Siloxane DPC Fluid
Appearance	Clear to Yellow Liquid
Specific Gravity	1.01
Flash Point	>67°C
Solubility	Soluble in Water
Vapour Pressure	<0.70kPa
Volatiles	<1%
Dilution Ratio	1:4 with clean water
Available Sizes	5L & 25L
Shelf Life (Undiluted)	Up to 2 Years
Shelf Life (Diluted)	Up to 6 Months

Storage & Safety

Store in dry conditions in original unopened containers. Keep out of reach of children.

The concentrate may cause serious eye irritation. Wear suitable eye and face protection when diluting and applying the product. Clean equipment immediately after use using detergent and water.

Why Choose BioDry ProSil?

BioDry ProSil delivers professional-grade damp proofing performance using advanced siloxane technology while retaining the ease of use and safety advantages of a water-based system.

Its deep penetration, fast curing properties, and long-lasting waterproofing performance make it an ideal solution for treating rising damp in residential and commercial masonry structures.