The vast majority of Irish householders have inadequate insurance cover on their houses, the Insurance Brokers' Association (IBA) has warned. Because of the dramatic increase in the cost of rebuilding houses in recent years, homeowners could find themselves tens of thousands of pounds short for the reconstruction costs in the event of a claim.

The cost of rebuilding a typical three-bedroom semi-detached estate house in Dublin has risen by 61 per cent since 1997. The IBA's research has shown that homeowners have not matched this rise by increasing the buildings sum insured under their house policies.

Many people have their building cover attached to their mortgage and do not remember to review the policy.

Some insurers have been writing to their clients to highlight the possibility that they may be underinsured. But according to Mr Paul Carty, chief executive of the IBA, houseowners should not wait until their next renewal date to take action. "Many companies will up the sum insured at no charge until the next renewal date. All it takes is a quick telephone call and instruction and the problem is taken care of," Mr Carty said. The IBA carried out this research because of increasing anecdotal evidence from its members that houseowners coming for renewals were seriously underinsured.

The implications are stark. Unless your house is adequately insured, in the event of a loss, your insurer will not pay the full cost of the repairs or rebuilding of the house.

In the case of a full rebuild of a Dublin house that cost £100,000 to build in 1997, a homeowner who has not correctly reviewed their policy could find their insurance cover falls short by approximately £30,000.

Ultimately it is the householder's responsibility to ensure that their property is adequately insured. The Society of Chartered Surveyors recently published average rebuilding costs in its Guide to House Rebuilding; anyone in a standard house can use it to calculate whether they are underinsured.