They may use Unique weld pins with integral-cupped head washers. Unfaced boards can then be completed with bolstered insulating cement, canvas, or weatherproof mastic. Confronted boards can be put in in the identical way, along with the joints in between boards sealed with strain-sensitive tape or glass material and mastic. https://freeecogrants.co.uk/diy-vs-an-agency-to-apply-for-eco-4-grants/