The most important thing to consider is what type of asbestos containing material is on the roof, (bound or unbound).
Bound asbestos, (in everything from old bakelite telephones to old toilets and corrugated roof sheeting) contains varying amounts of asbestos fibres, which as the name suggests are bound with another material. Corrugated asbestos sheets are usually 5-10% asbestos in a cement binder. Safe if handled correctly, dangerous if not.
unbound asbestos, can be in the form insulation material, flat asbestos insulation board, in old fire doors and as limpet (aprayed on insulation). This type of asbestos material is more dangerous, and the removal of such is a specialised job, and requires 28 day notification to the health and safety authority prior to the removal of the asbestos.
The important thing is to find out which type it is.
The roof of a cottage most likely has corrugated asbestos cement or asbestos slates or tiles. (most houses aged prior to mid 1990's would have asbestos slates or tiles), the risk is that limpet insulation was sprayed onto the roof as well. This would have to be examined (visually only) to see if there is a thin layer of material on the underside. If there is, it is a specialist job. If not the job is practical for any competent builder/DIYer.
To remove this you have to have the proper safety equipment, paper overalls, dust mask, and gloves, and babywipes to wash any exposed skin and tools etc when your finished.
Spray the entire area with a mixture of PVA glue (polybond or similar) and water to keep any dust down, keep well wetted. the glue helps contain any fibres. Cut of the bolts holding down the sheets with a bolt crop taking care not to damage the sheets. Lift the sheets down, carefully, (you may need an access lift of some sort to do this) taking care not to break them. The sheets can then be stacked, and double wrapped and taped in 1000 guage polythene, (proprietary sacks are also available).
All the tops of the bolts etc and any small bits which might have broken of should be placed in an appropriate bag and swan necked (twisted and folded over) and taped, then inside another bag which is swan necked as well.
Your tools should be wiped with the baby wipes, and the baby wipes placed in a similar plastic bag, your gloves, and overalls should be removed and placed in the bag, wipe your shoes or boots with the baby wipes, and your face and hands etc. Lastly remove your dust mask, and wipe your face again. The bag with your overalls and mask and wipes can then be sealed.
The bags and wrapped sheets should be clearly labelled asbestos.
To dispose of it, there are a number of companies around the country who can collect it from you. it is important to ensure that they have a collection permit from the local authority region in which you live to collect asbestos (check with the council for a list). These companies can then take it to the disposal sites or transfer stations for export another country for disposal.
you MUST get a C1 consignment note for this material, as it is hazardous waste and it is an offence to move this without one.
You local council should be able to advise you or you can look on the HSA's website
www.hsa.ie and follow the links for hazardous waste