Damp, Mould and Wall Seepage in Malaysian Homes: Causes, Fixes and Who Pays

中文 · Bahasa Melayu · Bahasa Indonesia

By Jason Lim, REN 84424 · IQI Realty · Checked on 10 November 2026

This guide is for home owners, landlords and tenants in Johor Bahru and the rest of Malaysia, including buyers from Singapore, Indonesia, India, China and MM2H. The short answer: damp (lembap), mould (kulat) and wall seepage almost always come from one of five sources: condensation, rain getting through the outer wall or windows, a pipe leaking inside the wall, water from a neighbouring unit, or rising damp from the ground. Find the source first, because each one has a different fix and a different person who pays.

The five usual causes of damp walls in Malaysian homes

Malaysia is warm and humid all year, and MetMalaysia expected this year’s northeast monsoon to start on 27 October 2026 (The Star, October 2026). The usual causes:

Cause	Where you usually see it	Typical clues
Condensation	Behind wardrobes, bathroom ceilings, near aircon units, closed rooms	Spotty black mould on the surface; worse where air does not move
Rain penetration (resapan air hujan)	Outer walls, window frames, top-floor ceilings, below balconies	Worse during or after heavy rain; peeling paint and powdery salts
Leaking pipe inside the wall	Walls next to bathrooms, kitchens and water heaters	Stays wet in dry weather; spreads from one point
Leak from a neighbour	Ceilings and shared walls in condos and terraces	Lines up with the neighbour’s bathroom, kitchen or balcony
Rising damp	Bottom of ground-floor walls, often in older landed homes	A tide mark near the floor, flaky plaster; little change with rain

Also check the aircon: a blocked drain pipe or an uninsulated pipe inside a wall or false ceiling can soak plaster like a pipe leak.

How to tell which one you have

• Watch the weather. Pencil and date the edge of the patch. If it grows after rain, suspect the outer wall, windows or roof.
• Meter test. Close every tap, read the water meter, and check again an hour later. If it moved, a hidden pipe may be leaking.
• Check the other side. Is there a bathroom, a neighbour’s kitchen or the outside behind the wall?
• Foil test. Tape kitchen foil tightly over the spot for a day or two. Moisture on top suggests condensation; moisture underneath suggests water coming through the wall.
• Call a professional if unclear. Surveyors, engineers and experienced contractors use moisture meters and thermal cameras to trace water without breaking walls. Check that any contractor is registered with the Construction Industry Development Board (CIDB), which the law requires of all contractors (CIDB, checked November 2026).

Keep dated photos: they are your best evidence if you later need the management, a developer, a landlord or a tribunal to act.

Is damp and mould a health risk?

The World Health Organization’s 2009 guidelines on dampness and mould found enough evidence to link damp, mouldy homes with respiratory symptoms, respiratory infections and worsened asthma. They put the main remedy on prevention: owners should keep buildings sound and dry, and occupants should manage water use and ventilation.

Malaysia’s Department of Occupational Safety and Health (DOSH, Jabatan Keselamatan dan Kesihatan Pekerjaan) published a 2019 guideline on mould for workplaces that is also useful for homes:

• Mould grows when relative humidity stays above 70%, and some moulds can begin to germinate within 4 to 12 hours.
• Left alone, it can spread in 24 to 72 hours, so wet materials that are not yet mouldy should be dried within 48 hours.
• Stop the water first, then clean. Hard surfaces can be cleaned with soap or detergent solution; porous materials such as carpet, gypsum board and insulation that cannot be cleaned should be removed in sealed bags.
• People with breathing problems or weak immune systems should not take part in the clean-up.

This is general information, not medical advice. If anyone at home has asthma or allergies, ask your doctor; after a flood, see my flood risk guide.

Common fixes, cause by cause

Cause	Usual fixes	Who to call
Condensation	Ventilation, exhaust fans, gaps behind wardrobes, a dehumidifier, fixing aircon drains	Usually the occupant
Rain penetration	Reseal windows, repair cracks and joints, exterior waterproof coating	Condos: the management; landed: a contractor
Pipe leak in the wall	Open the wall, replace the pipe or joint, dry, re-plaster	A plumber; in condos, the management if the pipe serves several units
Leak from a neighbour	Fix the neighbour’s waterproofing or pipe, then your wall	Condos: the management first; terraces: the neighbour
Rising damp	Repair or add a damp-proof course, replace salt-damaged plaster, improve drainage	A building surveyor or specialist contractor

Avoid painting over a damp patch before the source is fixed, or hiding it behind a new wardrobe. See my guides to hiring a contractor in JB and renovation permits. Running a dehumidifier or the aircon’s dry mode uses electricity; my JB electricity and water bills guide explains the tariffs.

In a condo: who is responsible for damp walls

Under the Strata Management Act 2013 (Akta Pengurusan Strata 2013, Act 757), responsibility follows the source of the water.

Shared walls: the party-wall rules

Part XVI of the Strata Management (Maintenance and Management) Regulations 2015 covers damage to a party wall (dinding dua pihak): a wall between two units, or between a unit and common property. Damage includes dampness and water penetration in the wall or in plaster, panels or gypsum boards fixed to it (regs. 65 and 66). Regulation 67 then applies the inter-floor leak procedure in Part XV:

1. Report in writing to the developer, the Joint Management Body (JMB) or the Management Corporation (MC) (reg. 56).
2. Inspection within 7 days (reg. 57), then Form 28 naming the cause and who repairs within 5 days (reg. 59).
3. Repair within 7 days of Form 28 by the owner named, or by the management for common property such as a pipe serving several units (regs. 58, 61, 62). If an owner does nothing, the management repairs and recovers the cost.
4. Access: refusing entry after 7 days’ written notice can mean a fine of up to RM50,000, up to three years in prison, or both (reg. 63).
5. Disagree? The Commissioner of Buildings (Pesuruhjaya Bangunan, COB) at your council decides (reg. 64).

For ceiling leaks, section 142 of the Act presumes the water comes from above unless proven otherwise; see my guide to water leaking from the unit above.

Outer walls, roof and windows

The Act defines common property as the part of the development not within any unit (parcel) and used, or capable of being used, by two or more units. The outer walls, roof and structure are therefore generally common property, and the JMB or MC must keep them “in a state of good and serviceable repair” (section 21 for JMBs; section 59 for MCs). Rain seeping through an outer wall is usually a matter for the management, paid from the maintenance charges or the sinking fund (see my maintenance fee and sinking fund guide).

Check your strata plan, and note that window seals and your own alterations, such as a closed-in balcony, may be treated as yours. If damage comes from an owner’s or tenant’s negligence or a by-law breach, the management can recover the cost from that owner (section 21(4)).

When the management does not act

Escalate to the COB at MBJB, MBIP or MPKu, then the Strata Management Tribunal (Tribunal Pengurusan Strata), which hears claims of up to RM250,000 (section 105) for a RM100 filing fee on residential property (KPKT, July 2025). See my Strata Management Tribunal guide. Not legal advice: confirm your case with the COB, the tribunal or a lawyer.

New homes: the defect liability period

For a home bought from a developer, the statutory sale and purchase agreement (Schedule G for landed, Schedule H for strata) gives a defect liability period (tempoh liabiliti kecacatan) of 24 months from vacant possession (since December 2007). The developer must repair defects such as damp from poor workmanship within 30 days of your written notice. If it does not, the agreement lets you give the developer the repair cost in writing and, if it still does not act within 14 days, carry out the work and recover the cost, including from the stakeholder sum held by the developer’s lawyer (Schedule H, defect liability clause).

For strata units, the regulations also send leaks caused by poor workmanship within the defect liability period to the developer (reg. 60). Claims of up to RM50,000 can go to the Tribunal for Homebuyer Claims (Tribunal Tuntutan Pembeli Rumah) under section 16M of the Housing Development (Control and Licensing) Act 1966. My vacant possession defect checklist covers what to test, and latent defects after the DLP explains your options once the period ends.

Landed homes: neighbours, roofs and rising damp

• Terrace party walls. Damp coming through a shared wall from a neighbour’s bathroom or garden is a neighbour matter, not a council one. Talk first, then put it in writing; see my neighbour and boundary dispute guide if it stalls.
• Roof leaks often show first as ceiling stains and mould on the top floor. Check the ceiling after heavy rain and clear gutters before the monsoon.
• Rising damp. Soil, planters or paving built up against a wall make it worse; keep a gap. Joints where an extension meets the original house also let rain in.

Tenants and landlords

Malaysia has no residential tenancy act in force yet; the government said in August 2026 that the Residential Tenancy Bill was still being finalised (Bernama). Until then, the tenancy agreement decides who repairs what.

• Tenants: report damp in writing with dated photos as soon as you see it, and keep rooms aired. Mould from a leak or defect is normally not tenant damage; mould from a room never aired may be argued to be.
• Landlords: act quickly. In a condo you deal with the management; a tenant generally needs the Strata Management Tribunal’s permission to file a claim (section 107), so the owner usually leads.
• At move-in and move-out: photograph walls, ceilings and the inside of wardrobes. My rental deposit refund guide explains deductions, and the landlord tenancy agreement guide shows repair clauses to include.

Does home insurance cover damp and seepage?

Only for the events (perils) a policy lists. Houseowner and householder policies commonly list sudden events such as burst pipes and tank overflow (Insuranceinfo, Bank Negara Malaysia’s consumer site, checked November 2026). Slow seepage and long-term damp are not among the perils it lists, so ask your insurer in writing whether they are covered rather than assuming. A condo’s master policy, which the management must take out under section 93 of the Act, covers the building, not your belongings. Read your own wording and report any claim promptly; see my home insurance guide.

Before you buy: signs to look for at a viewing

Where to look	What to look for	What to ask
Ceilings under bathrooms, kitchens and balconies	Stains, bubbling paint, a new false ceiling in one spot	Any leak, Form 28 or waterproofing repair in this unit or the one above?
Outer walls and window corners	Peeling paint, salts, black mould at window edges	Does it get worse in the monsoon? Has the management repaired the facade?
Ground-floor walls (landed)	Tide marks near the floor, flaky skirting	Any rising damp treatment or re-plastering?
Freshly painted patches	One wall or corner painted in a different shade	Why was this area repainted?

Ask the seller in writing about past leaks, and for condos read the AGM minutes for facade, roof or pipe works. My guides to subsale house inspection and checking condo management list the documents to request. Owners abroad: see managing a JB property from overseas. Foreign buyers should also note that Johor generally sets RM1 million as the minimum price for most homes bought by foreigners, with some exceptions (New Straits Times, April 2026; see my page on Johor’s foreigner minimum price).

Where to buy if this matters to you

Damp depends more on the building and its upkeep than the area, so judge each home on its own records. JB’s main markets:

• Mount Austin: newer condos and terraces popular with families.
• Iskandar Puteri: many newer homes, some still within the defect liability period.
• Tebrau, Setia Indah and Molek: older and newer landed homes side by side; check older ground floors for rising damp.
• Permas Jaya and Senibong: waterfront and older east-side condos; check outer walls facing the sea.
• JB Sentral and Bukit Chagar: high-rises near the CIQ and RTS Link station.

Compare them on my JB property map, or read condo vs landed vs SOHO to weigh who handles outer-wall repairs.

More Johor living guides: Water leaks from the unit above · Latent defects after the DLP · Flood risk in Johor Bahru · High floor vs low floor condos · Landed homes in JB

Frequently asked questions

Who pays for wall seepage between two condo units?

Whoever the inspection names. Under the Strata Management Regulations 2015 (Part XVI), the management inspects within 7 days, issues Form 28 naming the cause, and the owner named, or the management for common property, repairs within 7 days.

Is the external wall of my condo my responsibility?

Usually not. Outer walls and the roof are generally common property under the Strata Management Act 2013, so the JMB or MC repairs them. Window seals and your own alterations may still be yours; check your strata plan.

Is mould on my wall dangerous?

WHO’s 2009 guidelines link damp, mouldy homes with respiratory symptoms, infections and worse asthma. Fix the moisture, clean or remove the mould, and ask a doctor about any breathing problems. Not medical advice.

My new house has damp walls. Can the developer be made to fix it?

Within the 24-month defect liability period from vacant possession, notify the developer in writing; it must repair within 30 days. Claims of up to RM50,000 can go to the Tribunal for Homebuyer Claims.

Can my landlord deduct mould cleaning from my deposit?

It depends on the agreement and the cause. Mould from a leak or building defect is normally not the tenant’s fault. Report damp in writing with dated photos straight away.

Will a dehumidifier stop wall seepage?

No. It helps with condensation, but water coming through a wall from rain, a pipe or a neighbour must be stopped at the source.

Buying or renting a home in Johor Bahru?

Tell me which homes you are considering. At viewings I point out signs of seepage and mould, and I ask the seller about past leaks, repairs and any management records before you commit. You can also book an appointment, or a Zoom consultation if you are still abroad.

Sources: World Health Organization, WHO guidelines for indoor air quality: dampness and mould, 2009; DOSH (JKKP), Guidelines on Control of Molds Contamination and Remediation, 2019 (sections 2.3, 3.1, 6.1 to 6.4 and Appendix 2), checked November 2026; Strata Management (Maintenance and Management) Regulations 2015, P.U.(A) 107, Parts XV and XVI, regs. 55 to 67 (copy published by DBKL), in force 1 June 2015, checked November 2026; Strata Management Act 2013 (Act 757), sections 2 and 21 (copy published by DBKL), checked November 2026; Act 757, section 142, checked November 2026; Act 757, section 59, checked November 2026; Act 757, section 93, checked November 2026; Act 757, section 105, checked November 2026; Act 757, section 107, checked November 2026; KPKT, Soalan Lazim Tribunal Pengurusan Strata, updated 9 July 2025; MBJB, Info MBJB (Bahagian Pesuruhjaya Bangunan), June 2018; Housing Development (Control and Licensing) Regulations 1989, Schedule H, clause 30 (defect liability; 2002 text, period later extended to 24 months), published by the National House Buyers Association, checked November 2026; The Sunday Star, on the 24-month defect liability period from December 2007 (reproduced by the National House Buyers Association), 16 December 2007; Housing Development (Control and Licensing) Act 1966 (Act 118), section 16M, checked November 2026; CIDB, Contractor registration (Act 520, section 25), checked November 2026; Insuranceinfo (Bank Negara Malaysia), fire, houseowner and householder insurance, checked November 2026; Bernama, “Residential Tenancy Bill being finalised to balance rights of tenants and landlords”, 4 August 2026; The Star, “Start of Northeast Monsoon expected on Oct 27, MetMalaysia says”, 23 October 2026; New Straits Times, “Foreigners hit Johor property resale wall”, 20 April 2026

Jason Lim, REN 84424, IQI Realty Sdn. Bhd. E (1) 1584/6. General information checked on 10 November 2026, not legal, medical or technical advice. Get a licensed professional to inspect damp or structural problems, and confirm your rights with the Commissioner of Buildings at your council, the tribunal or a lawyer before you act.