They can also use Unique weld pins with integral-cupped head washers. Unfaced boards can then be finished with reinforced insulating cement, canvas, or weatherproof mastic. Confronted boards could be mounted in the exact same way, along with the joints concerning boards sealed with force-sensitive tape or glass fabric and mastic. https://freeecogrants.co.uk/how-can-an-agency-help-you-to-get-grants-for-loft-insulation/