Navigating Unauthorized Building Works in Hong Kong

Miss Wong purchased a unit from the 80s in North Point two years ago. At the time of purchase, the balcony was already enclosed with glass and had aluminum storage cabinets installed. In April 2025, she received a "Dangerous Building Notice" from the Buildings Department: enclosing the balcony was considered an "Unauthorized Building Works" (UBW) and must be demolished within 60 days. Failure to comply could result in prosecution and fines. Miss Wong is anxious: Can it be exempted? How to reduce the demolition costs?

1. What is "Unauthorized Building Works"? Is enclosing a balcony a "minor alteration" or an unauthorized structure?

• According to the Buildings Ordinance (Cap. 123), all structural alterations—including the addition of beams, glass curtain walls, enclosing balconies with aluminum windows—require prior approval.
• The "Minor Works Control System" only covers specified items (such as air-conditioner brackets, canopies with an area less than 5 m²).
• Enclosing a balcony usually involves reinforcing or altering the external wall, which is work that requires application for approval.

2. What options do property owners have upon receiving a demolition order?

• Comply with the demolition order (safest option)
  • Hire a registered contractor for demolition; prepare completion photos and circuit test report, reply to the Buildings Department within 30 days
  • Cost of works: glass curtain wall with aluminum frame
• Apply for "Minor Works Certification" (low possibility)
  • If the modifications are considered minor works, you can appoint a registered minor works contractor to submit drawings for certification
• Request an extension
  • You can submit a written request to the Buildings Department, stating financial difficulties or elderly residents without assistance

3. Impact on Listings and Mortgages

• Bank Valuation Decrease: With a demolition order in place, valuation firms usually deduct; some banks refuse to approve new mortgages
• Sales Contract Terms: Buyers may require the seller to demolish before completion, otherwise they can forfeit the deposit; if not demolished, a discount is needed

4. How to Avoid UBW Risks Before Buying a Property?

• Check the records: Whether there are "unauthorized building works"
• Inspect the balcony, window sill, rooftop in person: Pay attention to whether there are any added canopies or steel frames
• Ask the seller for a "completion certificate": If it is a minor work, there should be relevant proof
• Add a guarantee clause to the provisional sale and purchase agreement: If the government issues an order, the seller must be responsible for demolition or compensation

Once illegal additions are named, delay will only increase fines and valuation risks; the best solution to avoid lawsuits and price drops is to dismantle them as soon as possible. Before buying a property, check the records, review the plans, and ask the seller for compliant documents to truly buy with peace of mind and live with ease.