Perlfix vs Gyproc Adhesive Compared

Knauf Perlfix (sold in the UK as Knauf Plasterboard Adhesive) covers approximately 4.6 m² per 25 kg bag. Gyproc DriWall adhesive covers approximately 5.76 m² per 25 kg bag: British Gypsum states one bag fixes two 2400 x 1200mm boards under normal use. Actual coverage depends on wall flatness, as uneven walls require more adhesive for packing out. British Gypsum recommends dabs roughly 250mm long and 50-75mm wide, applied in vertical rows at 600mm maximum centres (three rows per 1200mm board), giving at least 20% contact area.

Perlfix has a working time of approximately 30-45 minutes once mixed. Gyproc DriWall adhesive has a longer maximum working time of 90 minutes per the Product Data Sheet. Both should be used promptly and not re-mixed once they begin to stiffen. In warm weather, working times reduce significantly, so mix smaller batches in summer.

Prices are very similar. Perlfix 25 kg bags typically cost £5-7 from builders merchants, while Gyproc DriWall 25 kg bags cost £5-8. Prices fluctuate and vary by merchant. Buying pallet quantities reduces cost to £4-6 per bag for either product. The price difference is negligible in the context of a full dry lining job.

Yes. Despite being different manufacturers, both adhesives are gypsum-based and work perfectly well with any plasterboard brand. Knauf Perlfix works with British Gypsum boards, and Gyproc DriWall adhesive works with Knauf boards. The key factor is correct mixing consistency and proper application technique rather than brand matching.

Neither product should be used on damp, dusty or painted backgrounds without proper preparation. Both require a clean, sound background with PVA or SBR primer on porous or dusty surfaces. For painted surfaces, cross-hatch the paint to provide a key. On very smooth concrete, both products benefit from a bonding agent. There is no significant difference in adhesion between the two on difficult backgrounds.