Repair Systems — 03 — Facade & External Envelope
Attapulgite clay + hydrogen peroxide poultice — organic stain removal
Technical product reference for attapulgite clay and hydrogen peroxide poultice systems for organic stain removal from masonry facades on Australian Class 2 strata buildings and heritage structures. Draws organic staining (moss, lichen, algae, bird droppings, tannin) out of masonry pores by capillary action during drying — suitable for acid-sensitive substrates including sandstone, limestone, and terracotta where acid cleaning is prohibited.
What is attapulgite clay + hydrogen peroxide poultice?
Attapulgite clay (palygorskite) combined with hydrogen peroxide at 3–6% concentration is the standard poultice formulation for removing organic stains — mould, algae, moss residue, lichen, bird droppings, tannin, and biological growth pigments — from masonry facades. The clay carrier draws the staining compound out of the masonry pore structure by capillary action as the poultice slowly dries; the hydrogen peroxide bleaches organic compounds within the paste. Suitable for all masonry types including acid-sensitive substrates (sandstone, limestone, terracotta) where acid cleaning is prohibited.
Product Reference
2 product systems — attapulgite clay + hydrogen peroxide poultice — scroll to view all
Attapulgite clay + hydrogen peroxide poultice — organic stain removal
Attapulgite + H₂O₂ poultice — organic stain removal — heritage and sensitive masonry
System Description
A traditional poultice for removing organic stains (mould, algae, moss, lichen, bird droppings, tannin, biological growth residue) from masonry on Class 2 strata buildings and heritage facades. Site-mixed from attapulgite (palygorskite) clay powder and hydrogen peroxide at 3–6% concentration. Apply at 10–15 mm thickness, cover with plastic sheeting immediately to prevent premature drying, and allow a full 24–72 hour dwell period. The clay draws the staining chemical out of the masonry pore structure as it dries by capillary action — the peroxide bleaches organic compounds within the paste without leaving toxic chemical residue. Suitable for heritage and acid-sensitive substrates (sandstone, limestone, terracotta, heritage brick) where acid cleaning is prohibited. Multiple applications are often required for deep or longstanding biological staining — allow 48 hours drying between cycles. Remove the dried poultice with a plastic scraper (not metal) and flush the surface with clean water. Identify the stain type before selecting — attapulgite + H₂O₂ is for organic stains only; oil and grease staining requires solvent-based kaolin poultice; rust staining requires a chelating agent or oxalic acid poultice.
Technical Properties
- Stain type: Organic / biological — moss, lichen, algae residue, bird droppings, tannin, coffee, mould
- Carrier: Attapulgite (palygorskite) clay — absorbs staining chemical out of masonry pores by capillary action during drying
- Active: Hydrogen peroxide (3–6%) — bleaches organic compounds within the paste without leaving toxic residue
Limitations
- Slow process — 24–72 hour dwell plus drying time between cycles; plan schedule accordingly for strata building remediation
- Not suitable for oil, grease, or hydrocarbon staining — specify kaolin + solvent poultice for these stain types
- Not suitable for rust or iron staining — specify proprietary chelating agent or oxalic acid poultice for rust removal
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Remmers IG Poultice — organic stain removal system
Proprietary attapulgite + H₂O₂ poultice — organic stain removal — heritage conservation
System Description
Remmers Australia manufactures the IG Poultice system — a professional proprietary attapulgite clay and hydrogen peroxide formulation specifically developed for organic stain removal from heritage and sensitive masonry substrates on Class 2 strata buildings, conservation works, and heritage-listed buildings. Pre-formulated for consistent carrier-to-active ratio — eliminates the risk of site-mixing errors that can under-dose the active or over-saturate the clay carrier. Product data sheet and SDS available from Remmers Australia — required for heritage council and local government conservation submissions. Tested and rated for use on heritage sandstone, limestone, and terracotta as well as fired clay brick. Apply at 10–15 mm thickness, cover with plastic sheeting to slow drying, remove after the full dwell period with a plastic scraper, and flush with clean water. Suitable for both Class 2 strata building organic stain remediation and heritage conservation works where documented product chemistry is required by the heritage consultant or authority. Multiple applications may be required for deep or historic biological staining.
Technical Properties
- Remmers proprietary formulation — consistent carrier-to-active ratio; no site-mixing errors; controlled H₂O₂ concentration
- Product data sheet and SDS available — required for heritage council submissions and local government conservation works approval
- Tested for heritage sandstone, limestone, and terracotta — confirmed non-destructive to acid-sensitive calcium-based substrates
Limitations
- Not suitable for oil, grease, rust, or complex multi-stain removal — specify kaolin solvent or proprietary rust poultice for these stain types
- Lead time may apply for specialist Remmers products — confirm availability before specifying for urgent remediation works
- Higher cost than site-mixed attapulgite and H₂O₂ — justified where heritage documentation, consistent formulation, or technical support is required
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of attapulgite + hydrogen peroxide poultice systems. Confirm stain type is organic or biological before selecting — wrong poultice on wrong stain type produces no result.
| Supplier | Product | Stain type | Carrier | Active | Distribution | Key feature | Primary use |
|---|---|---|---|---|---|---|---|
| Specialist masonry suppliers | Site-mixed attapulgite + H₂O₂ | Organic / biological | Attapulgite clay | Hydrogen peroxide 3–6% | Chemical supply / trade | Low cost; widely sourced | Organic stain — general masonry |
| Remmers Australia | Remmers IG Poultice | Organic / biological | Attapulgite clay (proprietary) | H₂O₂ (formulated ratio) | Remmers specialist supply | TDS / SDS — heritage documentation | Organic stain — heritage works |
Do not confuse attapulgite + H₂O₂ poultice with:
- Kaolin / paper pulp + solvent poultice — entirely different chemistry; for oil, grease, tar, and hydrocarbon staining only; do not use attapulgite + H₂O₂ for oil or grease stains — it will produce no result
- Proprietary masonry poultice with chelating agent — required for rust and iron staining; attapulgite + H₂O₂ has no effect on rust deposits; rust staining requires oxalic acid or thiourea dioxide reducing agents
- Acid wash (HCl, phosphoric, sulphamic) — entirely different application method and chemical mechanism; acid wash removes calcium deposits and efflorescence, not organic staining; do not substitute poultice for acid wash or vice versa
- Biocide treatment — biocide kills biological growth but does not remove the organic stain pigments already in the masonry pores; attapulgite + H₂O₂ poultice is applied after biocide treatment has killed the growth
- Cover the poultice with plastic sheeting immediately after application — do not allow the poultice to dry prematurely; premature drying reverses capillary extraction and redeposits the stain rather than removing it
Disclaimer
This page provides general technical information only. Poultice selection must be matched to the specific stain type and masonry substrate. Trial application on an inconspicuous area is required before full-scale treatment. For heritage-listed buildings, document all trial areas with photographs before commencing full treatment.