Finishing primer I.M

coatingsprayliquid

Why choose Primer IM?

• Pre-treatment assurance

Used as a pre-treatment before applying Passive Purple®, Airtight White® and Passive Purple® External, Primer IM consolidates and seals difficult dense substrates such as concrete bricks, calcium silicate stone and old lime renders. Its small-molecule microemulsion penetrates deeply into the substrate and, once absorbed, consolidates the surface acting as a primer. Water‑based dispersion coatings can then be applied.

Difference with Lime Prime
Primer IM has a much smaller molecular structure and is formulated as a microemulsion to be effective on dense substrates. Its small molecules penetrate deeply, providing consolidation and a priming function on dense materials (concrete, old lime). For bare, dusty, highly porous or lime-rich substrates, use Lime Prime instead.

Compatibility and behavior
Works in synergy with air and vapour control membranes from Intelligent Membranes due to its high vapour permeability. The primer accommodates subtle movements without cracking and follows the movements of older buildings, matching the high elongation characteristics of modern air/vapour membranes. Suitable for renovation projects where substrates may move.

Primer IM for refurbishment
Renovated walls are often dense, airtight or already painted. Primer IM consolidates the surface, improves adhesion and creates a sound substrate for Passive Purple®, Airtight White® and Passive Purple® External. Its flexibility and vapour permeability enable a durable airtight layer suitable for refurbishment standards such as those referenced by the BBA.

Uses / Application

• Application: apply at low pressure or with airless spray equipment in a single coat of approximately 100 g/m² (depending on porosity).
• Application methods: low-pressure spray (airless), airless gun, roller.
• Recommended substrates: old/dusty substrates; concrete bricks; calcium silicate stone; old lime; dense surfaces requiring consolidation before coating.
• Do not use on: bare, very porous or very dusty substrates without preparation (prefer Lime Prime).

Related guides

• Pre-treating dense substrates before installing airtight membranes
• The builder forgot the vapour control layer? How to rectify it
• Case study: improving adhesion with a primer in blockwork and insulated formwork construction
• What is airtightness (and why is it important for net-zero buildings)?

Datasheets and documents available

• Primer IM Technical Data Sheet (TDS)
• Primer IM Installation Guide
• Primer IM Safety Data Sheet (SDS)

Characteristics / technical specifications

• Commercial name: Primer IM
• Packaging: 10 kg
• Product type: primer / multi-purpose (microemulsion)
• Application: spray (airless or low pressure) or roller; single coat approx. 100 g/m² (depending on porosity)
• Recommended substrates: dense concrete, concrete bricks, calcium silicate stone, old lime, dense renovated walls
• Vapour permeability: high (compatible with air/vapour control membranes)
• Function: deep substrate consolidation, surface sealing suitable for water‑based topcoats
• Mechanical behaviour: flexible; absorbs small movements without cracking; compatible with high‑elongation membranes
• Compliance / references: suitable for refurbishment applications in line with BBA requirements (as stated by product literature)
• Product compatibility: designed for use prior to Passive Purple®, Airtight White® and Passive Purple® External