Their "Cold War" could have ended years ago if they had spoken to each other amicably from the start.
For 25 years, Mr Tan lived a nightmare, waging a war against his neighbour living upstairs.
He has requested anonymity for fear that his neighbour would terrorise him further.
It started off with dirty water dripping on his laundry after he moved into his four-room Bukit Purmei flat in the 80s.
"We were still on talking terms then, so I asked him to wring his clothes before hanging them out to dry," said the 72- year-old retiree who lives on the eighth storey.
"I told him to be reasonable." But his neighbour on the ninth storey, Mr Lim, now in his 60s, denied he was responsible.
Said Mr Tan: It had to be, the block is only 10 storeys high and I know the woman living on the 10th wouldn't do such a thing."
While the denial made Mr Tan upset, his accusation incurred he wrath of Mr Lim.
They stopped talking after that but the gripes grew in frequency and seriousness.
"My air-con compressor became a receptacle for rubbish thrown from upstairs. Once, he threw acid on my laundry and it burnt through my clothes," Mr Tan alleged.
Another time, a lit cigarette landed on his laundry pole, burning a hole in his T- shirt.
In recent years, Mr Tan claimed his upstairs neighbour took to throwing sand, paint and litter onto the common corridor outside his flat and jammed his mailbox shut.
A new law meant to help in neighbour disputes like Mr Tan's was passed in Parliament yesterday.
With the Community Disputes Resolution Bill, the disputes can now be settled in a new tribunal that gives parties new legal recourse if mediation fails.
But Mr Tan did not have the new law o help him in this case.
"My religion teaches me to love my neighbour but it's too difficult," he said.
When they bumped into each other at the lift lobby, both men refused to peak to each other.
The police were called in, but little could be done as there was not enough evidence to pin the blame on his neighbour.
So Mr Tan pent $1,500 to install a closed-circuit television camera at the common corridor and managed to capture his neighbour throwing cat faeces outside his home.
With the evidence, both parties were called to undergo a mediation session at the Community Mediation Centre (CMC) at Maxwell Road last year.
Mediation at CMC is not compulsory and any party an choose not to turn up.
"My guess is that he turned up because there was evidence, otherwise he would have continued denying it," said Mr Tan.
It was then that Mr Tan heard that Mr Lim's son was involved with loan sharks and had been harassed by them.
"He probably thought I was responsible but it really has nothing to do with me," said Mr Tan.
They cleared the air through the mediation session and were made to sign an agreement to live peacefully with each other.
But even now, Mr Tan said there is still an uneasy peace.
They remain agitated when they bump into each other, and they still don't talk to each other.
"If it happens all over again, I'll probably have to get the police involved but there is little else I can do."
STRICTER MEDIATION FOR DISPUTES
In the past, disputing parties could choose to ignore the agreement they signed during community mediation with little consequence.
With the new Community Disputes Resolution Bill, a special tribunal can impose court orders on parties to resolve the dispute.
A repeated breach of such orders can result in criminal liability, according to a fact sheet from the Ministry of Culture, Community and Youth.
Both parties are also compelled to turn up for the tribunal, said its Minister, Mr Lawrence Wong.
"The Tribunals will be an avenue of last resort to adjudicate long-standing, difficult community disputes where other efforts at resolution have failed," he said in Parliament yesterday.
Thirty per cent of cases at the Community Mediation Centre (CMC) remain unresolved.
The centre also sees a 60 per cent no-show rate - parties fail to attend about 900 out of 1,500 cases seen by CMC every year.
Said Mr Wong: "Living in close proximity with our neighbours can heighten sensitivity towards disturbances, such as noise, smells and what we perceive to be inconsiderate use of public spaces like the common corridor.
"These tensions could easily sour relations between neighbours, even when there are attempts to talk through the issues."
Lawyers and community mediators welcomed the new Bill.
Community mediator Jamunarani Manunethi, 53, said: "If one party refuses to turn up, there is no point for mediation.
"It should be a compulsory thing. Just meeting and talking about them together can solve many problems."
She mediates up to two cases every month at the CMC, and has been doing so for 15 years.
Madam Jamunarani has been in situations where a "solved" case came back to her because one party did not honour the signed agreement.
Lawyer Gloria James said she is in favour of the new tribunal as "it is clearly driven to meet and keep harmony".
Lawyer Steven Lam agreed, saying that if a failed mediation is taken to the courts, it's a "prohibitive cost to both parties and doesn't benefit anyone."
This article was first published on Mar 14, 2015.
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