Products & Materials

Rainwater Holding Stone

Rainwater Holding Stone(Porous Ceramic Carrier)

Rainwater Holding Stone(S)
Rainwater Holding Stone(M)
Rainwater Holding Stone(L)


  • Used as the main ingredient of loess natural organic matter
  • Maximize waste recycling and water purification functions
  • Adsorption/oxidation reactions of organic substances, nutrient salts, heavy metal substances, etc
  • Nitrogen oxidation and denitrification reactions by large and small voids inside
  • Adsorption and removal of ionic substances such as anions and cations
Specific gravity comparison
Microbial SEM (enlarged picture)

Related Certification Status

Removal of organic nitrogen and E. coli
[Patent No. 1065814]

Oil decomposition
[Patent No. 0866526]

Odor removal
[Patent No. 1173260]


  • LID related
  • Planter Box
  • Rain Garden
  • Grassed swale
  • Roof greening
  • Infiltration Trench
  • Artificial Wetland


Rainwater-retaining stone
(LID mulching agent)
Rainwater Holding Stone(S) Rainwater Holding Stone(M) Rainwater Holding Stone(L)
Size 3~5㎜ 5~8㎜ 13~5㎜
Main raw material Red clay, Clay Red clay, Clay Red clay, Clay
The external appearance Bead shape, ocher color, and mud brown, smooth surface and micropore formation Beaded, ocher-colored, smooth surface and microporous formation Rectangular, reddish brown, coarse and fine pore formation
Performance Weight 0.9~1.4g/㎤ 0.9~1.4g/㎤ 0.9~1.4g/㎤
Volume weight 0.72~0.85g/㎤ 0.75~0.95g/㎤ 0.75~0.95g/㎤
Porosity 62 61 61
Comparative area 1.0~3×10⁴㎠/g 1.5~3×10⁴㎠/g 1.8~5×10⁴㎠/g


  • Sulfur and clay, which are the main raw materials of rainwater, are rich in cationic substances and have excellent phosphorus adsorption ability contained in non-point pollutants.
  • The micro pores formed inside provide a space for microorganisms to inhabit and increase the reproduction density of useful microorganisms or specific microorganisms that contribute to the removal of pollutants.
  • Macropores (external pores) formed between uniform particles allow rainwater to pass through and play a role in increasing the permeability.
  • When used as a mulching stone, the aesthetic function of the natural color of red clay is provided, as well as the loss of vegetative soil due to rainwater.
  • It is possible to remove eutrophication-inducing substances (phosphorus, nitrogen) as well as oil pollutants by selectively integrating and applying specific microorganisms depending on the source of contamination.

Example of rainwater Holding Stone utilization

Rooftop Greening System Out Of Management

Tree Box Filter