Laterite Stone Construction: Where It Works, How to Build With It and What It Costs

Laterite is a sound walling stone for houses in Goa, coastal Karnataka, Kerala and the Konkan, provided you buy blocks that meet the Indian Standard, let them season before use, and design the house to keep water out of the wall. It is a soft, porous stone, so a laterite house lasts because of its eaves, plinth, mortar and plaster, not because the stone is strong.

What laterite is, and where it is quarried

The Indian Bureau of Mines describes laterite as an iron- and aluminium-rich surface formation made by long weathering of rock in hot, wet climates; the iron oxides make it red. The term was first used for deposits on the Malabar coast of Kerala and in Dakshina Kannada, and laterite caps hills and plateaus across the Deccan in layers up to 60 m thick (IBM, Indian Minerals Yearbook 2022: Laterite).

The BIS standard lists ten states, including Kerala, Karnataka, Goa, Maharashtra and Odisha, and calls laterite the weathered remnant of rocks such as basalt, granite and slate (IS 3620:1979). For house building, the belt that matters is the west coast:

• Goa. A geo-engineering study describes Goan laterite as deeply weathered ancient crystalline rock, cut into blocks with mobile circular saws, some of which harden on their own once exposed to air (Nichol, 2000).
• Kerala and coastal Karnataka. The Malabar coast and Dakshina Kannada, where the term began.
• Konkan Maharashtra and Odisha. Both appear in the IS 3620 list and in the IBM's resource tables.

Since February 2015 laterite has been a "minor mineral", regulated by state mining departments, so national production figures are patchy.

Block sizes and strength: what IS 3620 asks for

IS 3620:1979, Specification for laterite stone block for masonry, is the code to quote in your contract. The IBM yearbook records it as reaffirmed in 2022. Its main requirements are:

The foreword warns that laterite's properties "vary considerably from place to place". A study of freshly quarried stone from the Patradevi quarry in north Goa found an average compressive strength of about 5 MPa and water absorption of 11.45%, and concluded that Goan laterite is weaker than good brick (Das, 2008). The IBM is blunter: laterite "cannot withstand heavy pressure" and is used for light structures, partition walls and boundary walls.

Our guidance: ask the supplier for a lab test report for your lot covering strength, absorption and specific gravity, ask how long the blocks have been out of the quarry, and reject cracked or soft blocks.

How to build a laterite house

Most problems in laterite buildings come from water. The Goa study traced most defects at the Basilica of Bom Jesus to rain and rising moisture, and concluded that laterite's durability depends "on water tightness rather than strength". The section below shows where each defence goes.

Foundations and plinth

The Karnataka PWD schedule has items for laterite masonry in foundation, basement and superstructure, all in cement mortar 1:6 to IS 3620 (Karnataka PWD SR 2023-24, Vol 2). The weak point is the plinth: the Goa study blames rising damp partly on a missing damp-proof course. The earthquake code IS 4326 notes that a plinth band on top of the foundation wall "will serve as damp proof course as well" (IS 4326:1993).

Our guidance: on low, wet or clayey plots, ask your engineer whether the footing should be in rubble stone or concrete instead of laterite. Always finish the plinth with a continuous band or damp-proof course, and slope the ground and apron away from the wall.

Walls, mortar and earthquake bands

IS 4326 allows stone block masonry for bearing walls and, depending on the building category (which depends partly on seismic zone), asks for a minimum mortar grade and reinforced bands at lintel and roof level. The choice between load-bearing laterite with bands and an RCC frame with laterite infill is for your structural engineer. The 190 mm blocks give a wall about 200 mm thick before plaster.

Plaster it, or leave it exposed?

Exposed laterite can work, but Bom Jesus is a warning. According to the Goa study, Archaeological Survey of India records show that lime plaster was renewed before each monsoon until the 1930s, and most of the damage began after the thick walls were stripped of plaster. Later repairs made things worse: cement mortar used for re-pointing was too hard for the soft stone, and acrylic paint inside stopped the walls breathing.

Our guidance, drawn from that study:

• Leave laterite exposed only where deep eaves or verandahs shelter it from driving rain. Plaster the faces most exposed to monsoon rain.
• Point exposed walls with a mortar that is not harder than the stone, and keep joints full so water cannot sit in them.
• Use breathable finishes; a clear water repellent can help on exposed faces, but check how often it needs reapplying.
• Fit drip grooves under slabs and sills so water falls clear instead of running down mouldings into joints.

Termites

Termites do not eat stone, but they reach timber frames, roofs and furniture from the soil through cracks and joints. IS 6313 Part 2 covers chemical treatment of the soil under and around a building during construction, to form a barrier against subterranean termites (IS 6313 (Part 2):2001). Ask your contractor which chemical they will use and check that it is currently approved for termite control.

Is laterite a sustainable choice?

Laterite is cut, not fired. Blocks are sawn from the quarry face and harden in air (Nichol, 2000; IBM), so there is no kiln, unlike burnt brick. Local stone also means short haulage. The trade-off is the quarry itself: laterite is a minor mineral under state rules, and quarrying changes land and drainage. Our guidance: buy from a quarry operating with a valid state permit, and use the full block so less is wasted. For the wider cost-benefit picture, see our post on sustainable building in India.

Laterite stone price: what the official schedule says

We could not open a current Goa PWD buildings schedule or a Kerala PWD laterite item online, so we give no figure for either. To check prices locally:

• Ask the nearest PWD division office for the current Schedule of Rates item for laterite masonry.
• Quarries usually quote per block. A 390 × 190 × 190 mm block is about 0.014 m³, so about 70 blocks make a cubic metre before mortar. Use that to compare quotes with the schedule.
• Ask whether the quote includes transport and loading.

For what the walls mean for the whole house budget in Kerala, see home construction cost in Kochi, or try MOA's home cost calculator.

Laterite, brick or block: which is best?

Judge each material by the same measures (our guidance):

• Strength: laterite's 3.5 N/mm² minimum equals class 3.5 brick and the minimum IS 4326 sets for bricks and concrete blocks.
• Water: laterite may absorb up to 12% by mass under the code, so it needs more protection than dense stone.
• Cost: in the Karnataka schedule, laterite masonry costs less per m³ than brick masonry, and much less if the stone comes from your own plot.
• Upkeep: exposed laterite saves plaster and paint but needs eaves, careful pointing and resealing.

Mistakes to avoid

• Building with fresh, wet blocks. The code asks for about three months of seasoning out of the rain.
• Skipping the damp-proof course or plinth band.
• Pointing soft laterite with hard, cement-rich mortar.
• Bare, eaveless walls facing the monsoon, or non-breathable paint.
• Starting masonry in the monsoon. Plan the work as our house construction timeline suggests.

FAQ

Is laterite strong enough for a two-storey house?

The code sets a minimum of 3.5 N/mm², the same figure as class 3.5 burnt brick. Whether a load-bearing two-storey house works depends on your stone, the design and the IS 4326 bands, so let a structural engineer decide.

Does a laterite house need plaster?

Not everywhere. Sheltered walls can stay exposed with good pointing. Walls facing the monsoon last longer with lime-based plaster or a breathable water repellent, as the Goa research suggests.

What is the laterite stone price per cubic metre?

The Karnataka PWD Common SR 2023-24 gives ₹6,755 per m³ for laterite masonry in CM 1:6 above plinth, excluding GST, plus 12% in coastal areas. It is indicative only, so check your state PWD schedule and local quotes.

Talk to an architect who builds in laterite

Planning a laterite house? find an architect on MOA who can choose materials for your site and climate, or browse architects in Goa.

Sources

• Bureau of Indian Standards: IS 3620:1979, Specification for laterite stone block for masonry, via Public.Resource.Org (accessed 16 Oct 2026)
• Bureau of Indian Standards: IS 4326:1993, Earthquake resistant design and construction of buildings, via Public.Resource.Org (accessed 16 Oct 2026)
• Bureau of Indian Standards: IS 6313 (Part 2):2001, Anti-termite measures in buildings, pre-constructional chemical treatment, via Public.Resource.Org (accessed 16 Oct 2026)
• Indian Bureau of Mines: Indian Minerals Yearbook 2022, Laterite (accessed 16 Oct 2026)
• Karnataka Public Works Department: Schedule of Rates for Buildings 2023-24, Volume 2, and Common SR 2023-24, Volume 1 (area specific loading) (accessed 16 Oct 2026)
• Karnataka Public Works Department: Schedule of Rates 2024-25 page (accessed 16 Oct 2026)
• Das, S. (2008): Decay Diagnosis of Goan Laterite Stone Monuments, 11th International Conference on Durability of Building Materials and Components, Istanbul (accessed 16 Oct 2026)
• Nichol, D. (2000): The geo-engineering significance of laterite construction in Goa, SW India, Quarterly Journal of Engineering Geology and Hydrogeology 33(3), abstract (accessed 16 Oct 2026)