Property Clinic

Building a garden wall, moss on roof tiles and shared driveways

On the issue of wall height, it is necessary to have planning permission if the height exceeds 2m at the sides and rear, and 1.2m at the front along the public road

On the issue of wall height, it is necessary to have planning permission if the height exceeds 2m at the sides and rear, and 1.2m at the front along the public road


Q I am considering buying a three-bedroom semi-detached house. The garden adjoins the garden next door. I have a dog and would like to build a wall around the full perimeter. I was thinking of building it about 5ft high on each side and at the front with wooden gates. Do I need planning permission and permission from the neighbour?

A There are a number of issues you will need to consider. These include the precise alignment or position of the proposed wall and also its height. You do not indicate the nature of the existing physical boundary, for example if it is a hedge or a wall, or if you have more than one neighbour adjoining the perimeter on which you propose to build.

If there is an existing wall, you could approach the respective owners with a view to getting their permission to raise it. They may also agree to share the building costs. However, it is advisable to approach these future neighbours tactfully, as retaining good relationships is essential.

You will need your neighbours’ permission especially if you propose to remove or interfere with the existing physical boundary. Permission is essential if such activity involves crossing the legal boundary between your respective properties. You are entitled to build a boundary wall which would be located entirely on your side of the legal boundary. This would be difficult to achieve without reducing the net area of your garden, considering the width of excavation and foundation required for a wall constructed entirely on your property.

For such construction on the two sides of an average suburban residential property of 8m width and 26m length, this reduction in area would be about 10 per cent. On the issue of wall height, it is necessary to have planning permission if the height exceeds 2m at the sides and rear, and 1.2m at the front along the public road. You will need to discuss the wall height at the front with the planning authority to see if any height restrictions exist, such as traffic sight-line requirements.

However, an overriding requirement is that you do not unduly upset your neighbours. This may be the outcome if you buy this property and, from their perspective, make it look like a compound by building a 5ft perimeter wall to contain your dog. You should consider its visual impact, in particular at the front if other gardens have standard low-level walls or fences.

Niamh O’Reilly is chair of the Geomatics Surveying Professional Group of the Society of Chartered Surveyors Ireland,

Q Our house is 30 years’ old and the front faces north. The roof tiles are covered in moss and look very unsightly. We are wondering if there is any solution to this, and if there is a product that deals with this problem. The tiles are concrete and, of course, have now discoloured – the driveway also gets moss as well which is treated with moss killer.

A Moss and lichens can be quite troublesome and unsightly on older tiled roofs. This is caused by residual dirt left by the rainwater and is compounded by deposits of decaying leaves or spores or seeds either blown on to the roof or deposited by birds. The deposits encourage roots to grow on and between the tiles and this impedes the flow of rainwater, keeping the tiles damp and enhancing further vegetation growth.

Shallow pitched roofs and particularly north-facing aspects are more prone to moss or lichen growth as the latter is shaded from the sun and remains damp over longer periods of time. The moss may impede the flow of water into gutters and valleys and give rise to overflowing gutters. The profile of roof tiles often means that the drainage channels and overlaps need to be cleaned out and this can be time-consuming.

Toxic wash sprays in conjunction with stiff brushes can be used to remove moss growth. Be careful not to damage the tiles and avoid inhaling/ingesting the materials or letting them make contact with the eyes. Be aware that these products can be hazardous to adjacent garden plants, birds or domestic animals.

The sprays are best applied during dry weather as they often take several days to work and can be ineffective if diluted by rainwater. One treatment should be sufficient, but it may require several applications. This may need to be repeated after a number of years depending on the severity of the growth and prevailing conditions. More long-term solutions to prevent the reoccurrence of the problem could involve fixing copper wires across the roof surface – producing copper salts which oxidises on exposure to rain and has the effect of preventing further accumulation of moss or lichen on the roof.

While many DIY and gardening stores stock these products, in view of the safety and health implications of working on roofs and the hazardous characteristics of these toxic materials it is prudent to ensure only qualified professionals undertake this work and these can be sourced through reputable trade associations and suppliers.

Kevin Sheridan is a member of the Building Surveying Professional Group of the Society of Chartered Surveyors Ireland,

Q In my area we all have shared driveways and because the man who lived in our house before us built a wall around his front garden he ceded all of the shared driveway to our neighbour, making our front area smaller than it should be. When we moved in over a decade ago we were going to knock down the wall and look into building a wall up the centre of the shared driveway so we each got an equal amount and we had proper access to the side gate into our back garden (we have to hop over the wall and loop back to get to it).

Anyway, we never did anything about it in the end because while our neighbour (an elderly man who lives on his own) was agreeable in principle he would have had to move the pillar into his front garden and the pavement outside would have had to be dished to allow him to drive in. Most people on the road did this (the dishing) without planning permission but he was insistent we do it properly. We are wondering because he has had use of it for so long if he actually has rights to the driveway by now? I assume we would carry the costs of moving his pillar and any other associated works?

Very few people in the area use the shared driveway as it was originally intended, most have either divided it up with a wall or have paved over the entire front and have a massive shared driveway between the two houses. Also, a question I’d like to ask is if we don’t do anything about it, could it become an issue if we decide to sell the house?

AShared driveway issues tend to become problematic if they are not used as originally intended.

Such issues become more complex with the passage of time, in particular if there has been a change of ownership to one or both of the properties. This appears to be the situation in your case.

The usual arrangement is that the title in each property extends to the centre of the driveway. Each party has a right of way over the part of driveway on the adjoining property. You should check your deeds to confirm this. If it has not been formally ceded to him, your neighbour would need to have uninterrupted and unchallenged possession for 12 years before he could claim adverse possession. Your use of part of it would weaken his claim. Adverse possession is a complex issue and you should seek legal advice if it arises.

However, you state that your neighbour is agreeable in principle. You may not have a problem in achieving your objective if you remain on friendly terms and cooperate by carrying the costs of the work involved. He is correct in saying that you should do it properly, as the footpath is part of the public roadway. A road opening permit from the local authority is required for a minor extension to the dished portion, and possibly planning permission – depending on its extent or proximity to a junction etc.

If one or both properties are registered you should check with the Land Registry to ensure that revisions to the ordnance survey map, on which the Land Registry map is based, have not resulted in realignment of the registered boundary to the garden wall. It is, however, a “non-conclusive” boundary system.

You will need to formalise any revised arrangement and have the rights of ways removed as burdens from the respective Land Registry folios.

If not regularised, it is likely to become an issue if selling the house. All such issues affecting your title must be addressed when the purchaser’s solicitor requests the vendor’s solicitor to complete an “Objections and Requisitions on Title” document, prior to sale.

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Patrick Shine is a member of the Society of Chartered Surveyors Ireland,