Should I buy a property with a shared driveway and septic tank?
Property Clinic: Red flag issues require good legal, surveying or engineering advice
A shared septic tank could cause problems in the future in relation to tank capacity. Photograph: iStock
I am looking to purchase a property in the country, which has a property next door. Both properties are owned by one family. In the agreement of sale, yet to be written up, I would share the driveway and the septic tank. What is your view on the above?
At first glance, my advice would be to exercise a high degree of caution here as there are red flags present and you should proceed only with full knowledge of the facts and with the benefit of good legal, surveying or engineering advice. The red flag issues are, of course, compliance with planning permission, the shared septic tank and the shared access road.
In relation to compliance with planning permission, have your building surveyor or engineer determine if the shared septic tank arrangement complies with the enabling grant of planning permission.
You will also need to establish on whose site the septic tank is located; if not within the boundaries of the property you intend to buy (ie within your neighbour’s property), is there an easement in place to allow you to access, service and maintain it?
The local authority may insist that separate septic tanks
If the septic tank is located within the property you intend to buy, are you prepared to accept or to grant an easement to your neighbours allowing them to enter onto your lands for the purpose of servicing and maintaining the septic tank?
Then you come to issues such as septic tank capacity; does the tank have the capacity to meet the needs of both houses now and would it have the spare capacity to deal with any extra bathrooms you or your neighbour would build in the future?
The local authority planning department may refuse to grant planning permission for any proposed extension where the existing septic tank capacity is inadequate to deal with additional discharge. The local authority may also insist that separate septic tanks be installed and you would need to understand now whether you would be liable for those costs in that event.
Separately, in the event relations deteriorated between you and your neighbours, consider how that could affect your ability to enter onto their lands or vice versa for the purposes of maintaining or upgrading the shared septic tank.
Turning then to the use of a shared driveway, this is somewhat less precarious than a shared septic tank. Your solicitor will establish, then ensure that you have the rights to pass and repass over the road, and have the rights to lay pipes and cables underground or above ground.
We recommend that your solicitor draft up a maintenance agreement to deal with issues relating to the upgrade and maintenance of the private road. This is because the road is not local authority property and it will be a cost on you and your neighbour to renew, repair or replace the shared driveway as and when the need arises.
Thomas Moore, the American poet, said it best in the closing line of his poem Mending Wall: “Good fences make good neighbours”; the poem’s sentiment encourages the clear demarcation of property by means of a good fence; the idea of sharing a septic tank with a neighbouring property owner would be seen by many to contradict these sentiments. Proceed with caution and only with good legal, surveying or engineering advice. – John Corridan
John Corridan is a chartered general practice and valuation surveyor and member of the Society of Chartered Surveyors Ireland scsi.ie