At Roundtower Lime, we supply specialist cleaning solutions designed for the conservation and restoration of historic buildings, stone monuments, lime renders, and traditional masonry. These products are non-aggressive, biodegradable, and specifically formulated to preserve the integrity of breathable, sensitive substrates.
Our flagship cleaning product, D/2 Biological Solution, is trusted by conservators, architects, and heritage professionals worldwide for its safe, effective removal of biological and atmospheric staining — without compromising historic fabric.
D/2 Biological Solution
D/2 is a professional-grade, ready-to-use biological cleaning agent that removes mould, algae, red algae, mildew, lichen, and pollution-related staining from masonry and building surfaces. It is non-toxic, acid-free, bleach-free, and does not contain harmful salts — making it ideal for use on lime render, natural stone, brick, terracotta, and stucco.
Key Benefits:
-
Safely cleans without damaging delicate substrates
-
No mixing or dilution required — use straight from the container
-
Works with the natural elements — results develop over 1–30 days
-
Ideal for use on historic and listed buildings
-
Widely used on landmarks like The White House and The Alamo
Compatible Surfaces:
-
Lime render and limewash
-
Natural stone: limestone, sandstone, marble, granite, slate
-
Brick and terracotta
-
Cast stone and concrete
Two Methods of Application:
-
Immediate Results – scrub and rinse after 10–15 minutes
-
Passive Clean – spray and allow the elements to do the work over time
✅ Ideal For:
-
Heritage building facades
-
Churchyards and gravestones
-
Lime plasters and renders with biological growth
-
Conservation projects requiring non-invasive cleaning
-
Preventative maintenance on natural stone
❓ Frequently Asked Questions (FAQ)
Q1: Is D/2 safe for use on lime-based materials like lime render or limewash?
A: Yes. D/2 is specifically formulated for use on breathable, lime-based materials. It contains no harsh acids or salts and will not damage lime finishes.
Q2: Can I use D/2 on listed or protected buildings?
A: Absolutely. D/2 is widely approved by conservators and heritage organisations for use on sensitive and protected structures.
Q3: Does D/2 require rinsing?
A: Not necessarily. You can use the No Rinse Method by spraying the surface and allowing D/2 to naturally break down biological growth. For faster results, the Immediate Clean Method includes light scrubbing and rinsing.
Q4: Will D/2 prevent future growth of algae or moss?
A: While D/2 removes existing biological growth, reapplication may be required in areas of persistent moisture or shading to prevent regrowth.
