Most of our Singapore projects are HDB flats. 4-room BTOs in Tampines, resale 5-rooms in Bishan, older units in Queenstown being upgraded for the first time in 20 years. Mineral finishes work extremely well in HDB environments — but there are things worth knowing before you engage anyone.
HDB Renovation Rules — What's Relevant
For surface finishes specifically, HDB's renovation guidelines are relatively permissive. Painting, plastering, and coating work on walls and floors (excluding structural elements) generally does not require HDB approval. However:
- Hacking of existing floor tiles requires an HDB-approved contractor
- Waterproofing works in wet areas (bathrooms, kitchens) must comply with HDB standards
- Any work affecting shared walls or structural elements needs prior approval
For Lime Paint applied over existing walls: no approval required. For microcement over screed or after tile hacking: contractor must be registered with HDB where hacking is involved.
The Real Challenge: Substrate Condition
HDB walls and floors vary enormously by age and construction era. Here's what we typically encounter:
BTO Units (Post-2010)
Generally clean substrates — skim-coated walls, level screed floors. Good candidates for both lime paint and microcement. Moisture content is usually within acceptable range if the unit has been occupied for at least 6 months.
Resale Units (1990s–2000s)
More variable. Previous renovation coatings, tile-on-tile layering, and unknown waterproofing history mean substrate assessment is essential. We've encountered units where four layers of paint sit over the original skim coat — all of which need to be assessed for adhesion before anything goes on top.
Older Resale (Pre-1990)
Require the most care. Older HDB construction used sand-and-cement render that can be soft, friable, or damp. A mineral finish is only as good as what it's bonded to. Full assessment — and sometimes substrate repair — is required before proceeding.
Which Mineral Finishes Work Best in HDBs?
- Lime Paint — feature walls, bedrooms, living areas
- Microcement — bathrooms, kitchen floors, living room floors
- Lime Plaster — entrance walls, feature areas
- Liquid Metal — older HDB plaster may need reinforcement first
- Microcement on damp substrates — waterproofing must be resolved first
- Any finish over soft or friable plaster
Humidity in HDB Flats
Singapore's ambient humidity is typically 70–90%. In HDB flats — especially north-facing units with limited airflow — wall moisture content can be higher than expected even without visible dampness. This matters because:
- High moisture content causes adhesion failure in cement-based systems like microcement
- Lime Paint, being breathable, handles humid conditions significantly better than synthetic paints
- Units near the ground floor or with known water seepage history require waterproofing assessment before any surface work
Good news for HDB homeowners: Lime Paint was literally designed for high-humidity environments. Before synthetic paints existed, lime was what kept walls dry. In a well-specified HDB application, Lime Paint will last longer and perform better than standard acrylic emulsion.
What a Good HDB Mineral Finish Project Looks Like
Based on our HDB projects, here's what a proper job involves:
- Site visit and moisture assessment — before any quote is confirmed
- Substrate preparation — dust, loose paint, grease, and efflorescence removed
- Priming — appropriate mineral or mineral-compatible primer specified for the substrate
- Application — minimum 2–3 coats for Lime Paint, 5+ for microcement
- Protection — all furniture, floors, and carpentry masked and covered
- Curing time — respected before furniture reinstallation (24–72 hours depending on system)
Planning a renovation in your HDB?
We'll assess the walls, check substrate condition, and tell you exactly what's viable — before you commit to anything.
Book a Site Visit