I will most probably be buying a house in 4-5 years time. Would you advice to save up the house fund in bank or buy safe stocks and sell it 4-5 years later to fund for housing expense (reno etc.)?

Firstly, whats your definition of safe stocks?

Secondly, Do you currently have the amount that is sufficient for your housing expense? Or still saving up for it?

Suggestion: There are no such thing as safe stocks. Do note that Investment returns are never guaranteed but your housing expense in the future is. If you are able to take up some risk, perhaps apportion about 50% to 70% of the fund is lower risk products such as SSB, Fixed Deposit, Citibank Maxigain, or Single Premium Endowment Plans offered by Insurers from time to time. With the remaining fund, perhaps you can consider placing it in REITS or Defensive Industries to reduce your loss should a crisis occur

Never save to buy property, you will never buy when property price increase.

Buy what you can instead and upgrade later.