As title says....currently it is open with joists at 24 inch centres.If I use mainly 8 x 4 9mm plasterboard sheets, I guess the long sides will butt up to each other "longitudely" in the centre of every 3rd joist, as well as all along each edge, and I can nail 'em in place. However this leaves the ends ( 4 ' ) of the boards fixed by just the three places where they contact the 3 joists at right angles. ( if you see what I mean! ) Would this be acceptable, or will I have to fix extra wood pieces across joist to joist where thes board 4 foot ends are? I do Intend to have it all plastered afterwards. It is not going to be used as a "room" as such, just that it is very cold and hard to illuminate at present and I use it as a workshop quite a lot. Alternatively, any suggestions of other ways to achieve a good result - EPS Insulation sheets for example??
Also, will "external white masonry paint" be ok to use on the "breeze block" wall? The wall is also the house wall ( internal in other words) and shows no sign whatsoever of damp/ lime etc, ......unlike the opposite side of the garage which is single course common brick to the outside. Is there any special preparation I need to do before painting, apart from obviously brushing well to remove loose chips / dust etc. TYIA