putting plasterboard on the rafters

amandathepanda

We have had a loft hatch put in,insulation, the floor strengthened,a velux put in, and the loft boarded out, in our 1930's semi,and now to tidy it we would like to plasterboard the rafters. We have put up some 1L1 and now need to know how to fix the plasterboard on to some slaters lats.Any advice would be appreciated.

Browntoa

plasterboard screws are quickest,these come in 2 lengths , just pick the shorter ones


someone else might know but i'm not sure if you need to leave a gap between the roof felt and any insulation to allow air to circulate

nelly_2

Browntoa is right on both counts.

Definately use screws as hammering does losen slates/tiles, you thinking about belting the underside of your roof a few hundred times, and the air circulation gap is recommended at about 1 inch. Its to ventilate the wood in the roof so rot cant set in.

And if you really need to know plaster boards are supposed to be put on joist horizontally if the joist are verticle and vice versa. This is so the board goes on as many joists as possible. And wastage due to cutting can be up to 20%. The small boards (4 foot by 3 foot) are imperial length ways, for old houses set out in feet and inches. 6 by 3 and 8 by 4 are metric.

Rex_Mundi

If the boards are facing downwards, not vertical. Use 12.5mm plasterboard. The standard thickness (9mm) can end up sagging between fixings. The thicker boards are meant to be used on ceilings. This would also be better for you to use on your rafters.

tricky_3

Be aware that in boarding over the rafters, you will be cutting off the crossflow ventilation to the timber in the loft.....which may lead to long term problems. I would recommend some ridge tile vents as a minimum and a polythene vapour barrier between the plasterboard and the rafters. Also, if i was doing the job, to reduce cold bridging, i would use an insulation backed plasterboard.