What Are the Disadvantages of Indian Sandstone?
Across the UK, Indian sandstone paving has become one of the most recognisable and widely used materials for patios, garden paths, and outdoor living spaces. Its popularity is not accidental. For decades, Indian sandstone has offered homeowners a rare balance of natural character, workable strength, and sensible cost, making it a long-established choice within British landscaping.
That said, sandstone is a natural material with inherent characteristics that must be properly understood. Unlike manufactured paving, it rewards correct installation and regular care, while exposing shortcuts and poor preparation. This guide focuses specifically on the disadvantages of Indian sandstone, explaining how the material behaves, where its limitations lie, and how those limitations can be managed in real UK conditions.
The Natural Structure of Indian Sandstone
Indian sandstone is a sedimentary stone formed by compressed sand particles over millions of years. This geological process creates the layered structure, riven surface texture, and colour variation that distinguish natural stone paving from concrete or porcelain alternatives.
However, this layered composition also means sandstone is naturally porous. Microscopic voids within the stone allow moisture to enter and escape. This is not a defect, but it does influence how sandstone performs in the UK’s damp and variable climate.
Porosity and Moisture Absorption
One of the most commonly cited disadvantages of Indian sandstone paving is its ability to absorb water. In shaded gardens, north-facing patios, or areas with limited airflow, moisture can remain within the stone for extended periods.
During colder months, absorbed moisture expands when frozen. Repeated freeze–thaw cycles can lead to surface deterioration, flaking, or delamination if the stone is poorly installed or inadequately protected. This behaviour is not unique to sandstone, but sandstone’s porosity makes correct installation especially important.
Using a breathable impregnating sealer significantly reduces water absorption while still allowing the stone to release moisture naturally. Sealing does not remove porosity, but it reduces the long-term risk associated with moisture retention.
Staining and Discolouration Risks
Because sandstone is absorbent, it is more prone to staining than non-porous materials such as porcelain. Common causes include:
- Organic debris: Leaves, berries, moss, and bird droppings can introduce tannins and acids into the stone.
- Algae and lichen growth: Moist, shaded conditions encourage biological growth within the surface texture.
- Iron oxidation: Naturally occurring iron deposits within some sandstones can react with moisture and oxygen, producing brown or rust-coloured spotting.
Even denser varieties are not immune. Despite its reputation for strength and consistency, Kandla grey Indian sandstone can still display iron spotting under certain environmental conditions. This is a natural geological characteristic rather than a manufacturing fault.
Ongoing Maintenance Requirements
Indian sandstone should not be viewed as a maintenance-free paving option. Regular sweeping is essential to remove organic debris before it breaks down and stains the surface.
Periodic cleaning using pH-neutral stone cleaners helps control algae and surface contamination. One of the most common long-term issues arises from excessive use of high-pressure jet washing, which can erode the stone surface, open up pores, and accelerate future staining.
For larger formats such as Indian sandstone 900 x 600, consistent maintenance is particularly important, as staining or colour variation can appear more noticeable across larger continuous areas.
Variation in Quality and Thickness
Not all Indian sandstone performs the same. Differences in quarry source, layer density, and processing standards can result in noticeable variation in durability and thickness.
Lower-grade sandstone may be weaker, inconsistently calibrated, or more prone to surface delamination. Quality-controlled, calibrated sandstone—typically around 22 mm thick—offers far greater reliability during installation.
Whether installing single-size slabs or traditional Indian sandstone patio packs, calibration ensures consistent bedding depth, improved load distribution, and reduced risk of movement or rocking.
Chemical Sensitivity
Another disadvantage of Indian sandstone is its sensitivity to inappropriate cleaning chemicals. Many general patio cleaners designed for concrete or brick contain acids that can damage sandstone.
Acid-based products can etch the surface, react with iron content, and permanently alter the stone’s appearance. Only stone-specific, pH-neutral or biological cleaners should be used to avoid irreversible damage.
Installation Tolerance Is Low
Indian sandstone is unforgiving of poor installation. A full wet mortar bed is essential. Spot bedding or “dot and dab” methods create voids beneath the slabs, allowing water to collect and leading to reflective staining or surface marking.
Each slab should also be primed with a slurry bond bridge on the underside. This improves adhesion and reduces moisture migration from the mortar into the stone. Proper joint spacing, typically 8–10 mm, allows for natural movement and reduces stress over time.
Balancing Disadvantages with Natural Appeal
Despite these limitations, there is a reason Indian sandstone remains one of the most widely used paving slabs in the UK. Its natural variation, tactile surface, and traditional character are difficult to replicate with manufactured alternatives.
Porcelain paving offers lower porosity and reduced maintenance, but it lacks the organic variation and weathered charm that many homeowners associate with a true British garden.
Conclusion
The disadvantages of Indian sandstone—porosity, staining potential, maintenance requirements, and installation sensitivity—are not flaws, but inherent characteristics of natural stone.
When high-quality, calibrated materials are selected, installed correctly, and maintained sensibly, Indian sandstone delivers decades of reliable performance. For homeowners who value authenticity and long-term character over uniform perfection, sandstone remains one of the most rewarding paving materials available in the UK.
