Lining paper first? Or paint only?

Always best to fill cracks first than apply a sealer after that you can hang your lining paper crossways butting the joints I recommend not less then 1000 grade quality

Hi Roisin, From what you are saying the walls seem to be in a good condition, to prepare for painting I would wash the walls to remove any grease, use an appropriate filler for cracks. Sand filler and give the walls a quick rub down with 200 grade grit paper using a sanding pole (80-100 grade if walls are worse in areas) for a better finish. It is important that the walls are clean and free of any loose/peeling paint or dust. Use a white emulsion and apply 2 topcoats with a quality paint. As regards to lining paper, it covers flaws in the wall surface that paint can’t, but you can use a watered down filler to skim over the walls, and sand to remove these. Acoustically – 1 layer of wallpaper is equal to 70 layers of paint. You decide. As for lining on painted walls, assuming it is emulsion, wipe down the wall with water to remove any contamination and then apply a coat of watered down paste before hanging. Solvite have a few different ranges that apply to different wall coverings, so read the instructions first. Hope this helps Neil