Frequently Asked Questions
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Historic Maps – Missing Sections
The Historic Maps in our Historic map Viewer (6” and 25”) were scanned from the original series of County Maps, Geo Referenced and put into one National Historic data Set. In part due to the original scanning process there may be some gaps in the overall coverage of the maps. If you find such a gap you may inform us through our Customer Service Team on [email protected]. The gap will be filled by our Team as soon as possible after being informed however it can take up to 4 weeks for the update to appear on our Public Map Viewer.
Historic maps – Poor Quality in some areas
The Historic Maps in our Historic map Viewer (6” and 25”) were scanned from the original series of County Maps, Geo Referenced and put into one National Historic data Set. The quality of the outputted product is dependent on the quality of the original map. The scanning of the map does not improve the quality of the original. If you have purchased a map and are not happy with the quality please contact us on [email protected]. However, there may be times when the output quality of the Historic map cannot be improved on.
There is a mistake in one of your publications
How can I get it corrected and when will it be corrected? Your observation will be forwarded for the attention of the production team in our mapping department where it will be investigated thoroughly. Should a correction or addition be required it will be applied to our mapping database. However, as this is a printed product and cannot be rectified immediately it is the policy to apply the change or correction to the next published edition of the map. We appreciate your comments and interest in Ordnance Survey Ireland and our products.
What if my House Number is not shown or is incorrect on large scale mapping?
On our current mapping not all house numbers are shown. The process of correcting any omissions usually involves the deployment of Field Staff to survey the road or area in question. This work may fall under our normal update schedule and hence may take up to a year to appear in our mapping. If the matter is urgent please state the reason for the urgency and we will deal with the matter appropriately.
What if my Street Name is not correct on a map?
The naming of streets is the responsibility of the Local Authority in that area. The naming of streets is not the responsibility of the Ordnance Survey. If the name of a street is incorrect on one of our maps we will log it and proceed to correct the matter as quickly as possible. However, the process of correcting any omissions or errors usually involves the deployment of Field Staff to survey the road or area in question. It may also involve correspondence with the relevant local authority to confirm the particular name in question. For this reason the process of updating Street names can be lengthy. Also if the street name is incorrect on a printed map it will be corrected in the next edition. If the matter is urgent please state the reason for the urgency and we will deal with the matter appropriately.
What if a Building is omitted or incorrectly placed?
Should you know of a building that has been omitted or misplaced on an OSi Map you can inform us on [email protected]. There is also in place an online reporting service as part of the broadband rollout on www.mapreport.ie. A map marked with the omission should be attached or please supply Co-ordinates as this assists us greatly in pinpointing the area in question. The process of correcting any omissions or errors usually involves the deployment of Field Staff to survey the road or area in question. In some cases this work may fall under our normal update schedule for that area and hence may take up to a year to appear in our mapping. If the matter is urgent please state the reason for the urgency and we will deal with the matter appropriately. Please see below the areas and times scheduled to be updated in 2015.
My building is not correctly shaped?
The depiction of a building is a cartographic representation of what is on the ground. The actual shape of the building may not be depicted on our map as it is in reality on the ground. However with the improvement of better quality digital imagery OSi may develop a workflow to improve building shapes particularly in Rural areas.
Can an Ordnance Survey Ireland map indicate where my legal boundary is?
No. Ordnance Survey Ireland mapping does not depict legal property boundaries nor do we attempt to show property ownership on our mapping.
OSI only show the existence of physical features on the ground at the time of survey, which are surveyed to Ordnance Survey Ireland specification and accuracy standards. Although some property boundaries may be coincident with surveyed map features, no assumptions should be made in these instances.
Physical features on the ground change over time, and for this reason, Ordnance Survey Ireland has a continuous mapping revision programme. In the event that there are changes to the physical features on the ground, this may involve our surveyors visiting your property so that the mapping can be updated and amended. However, such revision will not affect legal land ownership and title deeds of a property and registered title will not change unless authorised by the Property Registration Authority.
What feature does the line on the OSI map represent?
Ordnance Survey Ireland maps use the same line symbol for a wall, fence, hedge, bank, ditch and stream. Where many features are represented in close proximity it may not be possible to represent them all at the scale of the mapping and it may not be obvious from the map which feature the line represents.
Even if a correct interpretation of the map can be made, the line on the map may not be the legal boundary. It is the position of the actual feature on the ground, not the position of the line on the map that is important in attempting to trace the position of the boundary.
Accurate analysis of the OSI map can usually only be achieved by taking the map onto the site and comparing it with the features on the ground. This can help decide what has been shown, what has been omitted for the sake of clarity or because the map scale does not allow multiple features in close proximity to be shown.
There is a fence and a wall next to each other and only one line is shown on the map, why is this?
Where a fence, hedge or wall runs approximately parallel to another feature and so close that they cannot both be plotted correctly at the scale of survey, then only one feature is shown.
I feel that a feature is incorrectly shown on the OSI map; can you tell me why it is represented this way?
Unfortunately Ordnance Survey Ireland does not keep records or surveyors’ notes of site visits. The map becomes the only record kept. The OSI in certain circumstances could comment on the detail of specific features shown on the mapping or provide reasons why or how a feature is shown on the map by reference to Historic maps held in the Manuscript stores.
I believe Ordnance Survey Ireland’s mapping of my property is incorrect, can I arrange for a surveyor to come out and amend the mapping?
Ordnance Survey Ireland welcomes all customer feedback about the content and accuracy of our mapping. We understand that there may be a delay between changes taking place on the ground and when we are able to capture them within our continuous mapping revision programme. Any issues relating to the content or accuracy of our mapping that fall within our specification will normally be investigated at the next revision of the mapping for the area. If the matter is urgent please state the reason for the urgency and we will deal with the matter appropriately.
I require an Expert Witness to comment on the mapping, does Ordnance Survey Ireland offer this service?
In property disputes i.e. land which both parties claim ownership, the courts look to Ordnance Survey Ireland to help. In all cases the signed 6” Boundary Sheet is accepted in Court as a legal map. OSI has been subpoenaed to court on numerous occasions to comment on OSi mapping.
◦The Society of Chartered Surveyors (SCS) provides a searchable database of Land Surveyors who can act as Expert Witnesses and prepare evidence for court.
◦The Irish Institution of Surveyors also provides a searchable database of Land Surveyors who offer a similar service
Can I measure my boundary precisely from the map?
It is not possible even when using the highest order of survey techniques to achieve perfect accuracy when drawing/digitising features on a map. OSI maps are therefore subject to accuracy limitations. This means that scaled measurements between features shown on the map may not exactly match the actual distance measured between the same features on the ground. Different levels of accuracy apply depending upon the scale of the map and the original method used to create it.
Paper maps (particularly copy maps included in deeds) can be subject to distortions and inaccuracies, as any copying processes (such as photocopying, scanning) and printing processes can lead to the distortions in the map image.
Can I get a folio number from OSi?
No, that is the responsibility of the PRA.
Can I get the ownership boundary on OSi maps?
When were the Historic maps surveyed?
One of the earliest known maps of Ireland was produced by Baptista Boazio in 1599. This predates the establishment of the Ordnance Survey by more than 200 years. At the end of the Cromwellian Wars in Ireland, the victorious soldiers had to be paid, so it was decided to pay them with the land confiscated from the rebels. William Petty undertook the survey of the forfeited land and this became known as the
“Down Survey” because it was plotted down and reproduced on paper.
Grand Juries who were the forerunners of the County Council also commissioned maps of their areas. So, it can be seen that Ireland was very well mapped before the establishment of the Ordnance Survey.
ORDNANCE SURVEY 1824.
Early in the nineteenth century it became obvious that the local taxes which were based on townland units in Ireland were inequitable. On the recommendation of the Spring Rice Committee, a survey of all Ireland at a scale of six inches to one mile was authorised by Parliament in 1824.
FAMINE 1845 – 1849.
After the potato famine, many Irish landlords were forced by economic pressure to sell their properties and an “Encumbered Estates Court” was established in 1844 to deal with the flood of land transactions. The Judges found the six inch map too small for the precise area calculations required and eventually the Ordnance Survey was asked to supply estate maps which were replotted at 1:2,500 from the six inch field books and then field revised.
In 1863, Griffin requested that Dublin be resurveyed at a scale of 1:2,500. Subsequently, all of Ireland was resurveyed at this scale.
1912 – 1960
The Chief Boundary Surveyor appears to have stopped signing supplementary boundary sheets in 1912. With the outbreak of the First World War in 1914, the uprising in 1916 followed by the war of Independence little mapping was carried out. The Government of Ireland Act 1919 set up the Parliaments for Ireland one for the North, the other for the South. It states that the Parliamentary boundaries of Antrim, Down, Fermanagh, Londonderry, Armagh and Tyrone are the areas for Northern Ireland and the remaining counties are the South. This is how the land frontier evolved. In 1924 the Ordnance Survey was transferred from the Department of Agriculture to the Department of Finance. At this time there was little mapping carried out due to limited resources.
The Foreshore Act was enacted in 1933. In this Act the word “foreshore” means the bed and shore below the line of high water of ordinary or medium tides of the sea and of every tidal river and tidal estuary and of every channel, creek and bay of the sea or any such river or estuary.
1:1,000 mapping was started in the early 1960’s Boundaries were transferred from the 25” county services.
N.P.S. mapping was started in the early 1990’s Boundaries were transferred from the 25” county series.
How often are maps updated?
Typically we had a large Scale Revision Cycle as follows
1:1000 Urban Mapping — Annually
1:2500 Suburban Mapping — Annually
1:2500 Peri-Urban Mapping — 3 years
1:5000 Rural Mapping– 5 years
However with the creation of prime 2 we will be moving into a more theme based revision depending on customer needs.
Ask On Support
If you have any questions and can’t find an answer in our FAQ’s, you can email our Customer Service team who will be very happy to help you.