Five years ago, I purchased a house with planning permission for an extension of one room at the side of the property. The original owners had laid the foundation and cement floor for the room but never completed the extension. I wish to complete the extension now as per the original planning permission. Do I need to seek fresh planning permission to do this?

Generally speaking, an applicant has five years in which to complete a structure up to wall-plate level before the grant of planning permission expires. If five years have not passed since the date of the final grant, you can apply for an extension of the grant of permission for another five years. To qualify for this the work must already have started among other requirements, one of which is that “substantial works have been completed according to the Planning and Development Act 2000″. This is generally accepted to mean blockwork up to wall-plate level or, in other words, blockwork is complete to roof level and ready for the roof timbers.

It sounds like you are out of time on this but it would be worth checking the exact dates to see if you have time to complete the blockwork to wall-plate level and could, therefore, avoid reapplying. Of course, your next problem will be getting a block layer to complete the blockwork in a timely fashion.

If your planning permission has expired you will have to submit a new application to the local authority to complete and retain the extension development. If you find yourself in this position, here are some things to be aware of:

1. There is no guarantee planning permission will be granted again as there may be new neighbours who could object; however, the risk of this is low, and where there are new neighbours, you might manage the risk by dropping into them and talking through the plan.

2. It is a good idea to check the planning file for any previous objections (forewarned is forearmed). Also, look at the planner’s report and make yourself aware of any conditions attached to the existing grant of permission, which you should ensure are met in your design.

3. Consider employing the same architect the previous owner used as they will be familiar with the development and planning process.

Before commencing the reconstruction works there are a number of things you would need to do:

1. Check whether the foundations and floor slab were inspected by a surveyor, architect or engineer when laid. If not, consider a trial hole inspection to make sure they are adequate;

2. Check the floor screed for dampness — consider any damage to insulation due to exposure for a long period of time;

3. The building regulations may have changed over the last five years and if they have, the extension initially applied for is unlikely to meet current regulations. A redesign will likely be needed, particularly with regard to document L: Conservation of Fuel and Energy;

4. Consider the building control (amendment) regulations (BCAR). Will you choose to opt out of the need to appoint an assigned certifier or a design certifier and the requirement to have staged inspections of one-off houses and extensions, or will you be complying with full BCAR provisions?

5. On completion of the works you will need certificates of compliance to show you have complied with both the planning permission and building regulations. I would expect some difficulty with certifying compliance with a design that is five years old and with certifying that the works completed to date meet current regulations. Make sure you employ a construction professional to do basic inspections to facilitate the issuing of these certificates.

• Pat McGovern is a chartered building surveyor and a member of the Society of Chartered Surveyors Ireland, scsi.ie