There has been a massive surge in tenants lodging complaints against landlords hiking rents in the middle of the worst housing crisis in the country's history.

The Residential Tenancies Board (RTB) has seen complaints over unfair rent hikes increase by almost 70pc in the space of one year as tenants struggle to meet the demands of international rental agencies and private landlords.

There has also been an increase in the number of illegal eviction cases the agency dealt with during the same period.

In 2014, the RTB dealt with 185 disputes over rent being higher than the market rate.

This jumped to 313 cases last year and already 66 disputes have been lodged in the first three month of this year.

However, housing charity Threshold says this is just the tip of the iceberg as most tenants do not lodge disputes with the RTB.

The charity believes there is a lack of awareness among renters of their rights and they also fear taking on rental agencies which have lawyers and economists to back up their claims.

It has also emerged some rental agencies are breaching the strict new tenancy rules and issuing rent increase notices outside the timeframes set out in legislation.

Landlords and agencies must give tenants three months' notice ahead of a rent increase and these notices can only be issued every two years.

Effectively, under the new rules, rent can not be increased for at least 27 months in total. However, in some instances landlords are issuing rent increase notices before that period elapses.

Threshold Dublin coordinator, Stephen Large, said there is a responsibility on those renting houses, especially private companies, to be aware of the new rules.

"You would believe it is their business to be aware of the rules and ignorance is no defence in terms of legislation and their obligation," Mr Large said.

He urged more tenants to challenge rent hikes to break the stranglehold landlords have on the rental market.

"They need to be challenged but people do not dispute rents as much as they should," he added.

Mr Large said the "big players" in the rental market "lawyer up" when rent disputes are lodged with the RTB which puts the average tenant at a huge disadvantage.

"The intention when the legislation was being drafted was maybe of two equal partners sitting down over a latte and a cappuccino and discussing the terms of how they are going forward but I don't think it's built for the current market conditions," he said.

Figures supplied by the RTB show an increase of almost 20pc on the number of disputes lodged with the agency in the first three months of 2016 when compared to last year. Six out of 10 cases are lodged by tenants, while landlords account for 40pc of the disputes.

Most disputes centre on rent deposits and rent arrears - last year they accounted for more than 1,200 cases.

There was 320 'unlawful termination of tenancy' or illegal eviction cases last year, which is a 40pc increase on the number of disputes registered in 2014.

Mr Large said most queries Threshold receive are around rent increases and security of tenure.

"A lot of the cases we get do not seem to be going to the RTB and I think part of the problem is the delay in getting cases heard," he said.

"There is a bit of uncertainty as well as the RTB could find in the landlord's favour and you could be liable for backdated rent," he added.

When rent hikes are disputed there is an onus on landlords to justify increasing the costs.

There is no central register for proving rents are in line with market increases and prices for similar accommodation in the same area.

The RTB has a rent index which is used as a guideline for disputes.

Sunday Independent