Mixing and Jointing Instructions

Mixing Instructions for Setting Compounds¹

For best results and coverage use a low speed drill mixer.

1. Ensure mixing equipment and water are clean.
2. Use 1.2 - 1.3 litres of water to 2 kg of powder (12 - 13 litres of water per 20 kg bag).
3. Place the water into a bowl and sprinkle the compound into the water.
4. Mix to a creamy consistency. Allow soaking for 2 - 3 minutes then adjust the consistency for use.

It is easier to mix the product too thick and add water.

  • Do not mix with other wet or dry materials

  • Do not retain product that has started to harden or intermix with previously prepared material

  • Do not overmix the material, as unnecessary agitation will introduce air bubbles

¹ GIB® TradeFilla's™ mixing instructions are slightly different. Refer to the instructions on the rear of the bag. 


Jointing Instructions

Winstone Wallboards recommends the use of GIB® Jointing Tape only.


  • Ensure that all fixings, screws or nails, are seated below the surface of the GIB® plasterboard. Any fixings that are driven too for into the GIB® plasterboard will cut the paper of the board causing problems such as 'nail pops'. If the fixings are proud, screw or hammer to just below the surface of the GIB® plasterboard
  • Tidy up any damaged areas of GIB® plasterboard such as broken corners. It is usually easier to remove these completely and fill them with a plaster based (setting) compound prior to continuing
  • Remove any dust or loose material from the GIB® plasterboard


First Coat

1. Using a 150 mm broad-knife, fill the recess formed by the taper edges of the sheets with GIB® basecoat jointing compound.
2. Centre the paper tape along the joint and using a 150 mm broad-knife press the tape down into the compound.
3. Draw the broad-knife along the joint to remove any trapped air bubbles beneath the tape. Ensure that sufficient compound is left behind the tape to achieve a good bond.
4. Immediately apply a thin coat of compound over the surface of the tape. This reduces the possibility of the tape curling and wrinkling which can lead to edge cracking.
5. When the compound is green (set but not dry), lightly scrape back any build up of compound along the joint. Note: Scrape back can be done as soon as 20 minutes after the product is too thick to trowel. At this point the product will still be plastic, and care is needed not to damage other areas. If left for an hour after it has become too hard to trowel, scrape back is easy and remains so for a further one to two hours dependent on weather conditions (hotter weather shortens the time available).
6. If an area needs to be scraped back when the product is dry, sponge water onto area before scraping back.

Second Coat

7. Apply a second coat of GIB® basecoat jointing compound with a 200 mm trowel. Ensure that this coat extends at least 50mm beyond the edges of the first coat.
8. Feather the joints to eliminate build up of the compound atthe edges.
9. Lightly scrape back any build up of compound along the joint as outlined in step 5 above.


Top Coat

For top coating Winstone Wallboards recommends the use of a GIB® air drying finishing compound.

Refer to the reverse of the relevant pack for instructions specific to the chosen product.

For further information on jointing corners, butt joints, stopping nail and screw heads or decoration refer to the GIB® Site Guide or contact the GIB® Technical Helpline on 0800 100442.