Description
Atlas Gipsar Plus is a gypsum skim for both the first and the last coat, sold here as a dry powder in a 20 kg bag. You mix it with water on site and use it to skim walls and ceilings indoors, level a wall before the finish and fill small holes, all from the same bag. It is a finishing gypsum plaster to C7/50/2, reinforced with polymers for a harder surface, and it takes paint or wallpaper once dry. It sits with the rest of the finishing plasters and fillers at Renders World.
What Atlas Gipsar Plus Does
Most skims ask you to pick one product for levelling and another for the final smooth coat. Gipsar Plus is made to do both. You can level an uneven wall, fill a small cavity and then go over it with a smooth finish coat from the same mix, which keeps the job to one material and one way of working.
Atlas lists four jobs for it:
- Skimming walls and ceilings to a smooth finish.
- Levelling the wall before the final coat.
- Filling small holes and cavities up to 10 mm deep, covered afterwards with a finish coat of Gipsar Plus.
- Skimming plasterboard over its whole surface, to finishing levels Q2 to Q4.
It goes on concrete, cement and cement-lime plaster, gypsum plaster and plasterboard. The finish takes paint coats and wallpaper. For taping plasterboard joints, Atlas sends you to a jointing compound instead, so tape the joints first and skim over them with Gipsar Plus.
Why Choose This Gypsum Skim
- One bag for start and finish — levelling, filling and the final smooth coat all come from the same powder.
- Trowel, roller or machine — work by hand on a small room, or spray it on a large one. For roller work Atlas recommends a scotch-brite type pile roller such as the Atlas Rollo Finish roller.
- Next coat after 1.5 hours — the second coat can go on wet-on-wet or on a fully set first coat.
- Colour changes as it dries — you can see which parts of the wall are ready.
- Hard, smooth surface — polymer resins make the set skim harder and more resistant to scratches, so it sands evenly by machine or by hand and takes paint well.
Atlas Gipsar Plus Technical Data
| Property | Value |
|---|---|
| Type | Gypsum skim for start and finish coats, dry powder |
| Classification | Finishing gypsum plaster C7/50/2, PN-EN 13279-1 |
| Pack | 20 kg bag |
| Coat thickness | Up to 5 mm per coat, up to 10 mm in all |
| Consumption | About 0.8 kg per m² for each mm of thickness |
| Water | 7.0–9.0 l per 20 kg by hand; 8.0–10.0 l by machine |
| Soaking time | 5 minutes |
| Working time | About 1 hour after mixing |
| Next coat | After 1.5 hours, wet-on-wet or on a set coat |
| Working conditions | +5 °C to +25 °C, room humidity up to 70 % |
| Application | Trowel, roller or spray machine |
| Reaction to fire | A1 |
| Shelf life | 12 months from the production date on the bag |
| Goes on | Concrete, cement and gypsum plaster, plasterboard |
How to Apply the Skim
Prepare the Wall
The wall must be stable, dry, even and clean, with no dust, dirt, lime, oil, grease, wax or old oil and emulsion paint that would weaken the bond. New Atlas cement plaster needs at least a week for every centimetre of thickness, and a concrete wall at least 28 days. Remove mould first with Atlas Mykos Plus, and protect any steel that will touch the skim against rust.
Prime only where the wall needs it. A very absorbent wall takes Atlas NKP primer undiluted, or Atlas Uni-Grunt Ultra. A smooth, low-absorbency wall such as concrete, or one with a coating that limits adhesion, takes a bonding coat of Atlas Ultragrunt.
Mix and Apply
- Mix. Pour the powder into clean water in a clean bucket: 7.0–9.0 litres per bag for hand work, the top of 8.0–10.0 litres for a machine. Leave it for about 5 minutes, then mix by hand or with a drill and paddle until there are no lumps. Old set gypsum left in the bucket makes a fresh mix set faster, so start clean. Use the mix within about an hour.
- By trowel. Use a smooth stainless steel trowel and smooth as you go. On walls, work in strips from floor to ceiling with an upward stroke. On ceilings, work in strips from the window into the room, pulling the trowel towards you. Trowels and spatulas are in the skimming blades and spatulas range.
- By roller. Spread the skim evenly with a scotch-brite type pile roller, then smooth the coat with a stainless steel trowel straight away.
- By machine. Spray from 1 to 1.5 m away in horizontal, overlapping strips, then level with a steel trowel straight away. If the work stops for more than an hour, flush the hopper and hose with clean water.
- Second coat. Apply it after 1.5 hours, wet-on-wet or on the fully set first coat. Keep each coat to 5 mm and the whole skim to 10 mm. For filling holes, mix it a little thicker than for skimming.
- Sand. Once dry, sand by machine with suitable discs or by hand with sandpaper or sanding mesh. Thin out any flaws with a fresh skim on a dampened surface and sand again.
- Paint or paper. When the skim is dry, prime it as your paint maker says, for example with Atlas Base Coat Paint, then paint with an acrylic or latex paint, or hang wallpaper.
Keep direct sun and draughts off the wall while it dries and air the room well. Wash tools in clean water straight after use.
Gipsar Plus or a Ready-Mixed Skim?
All three are Atlas skims for interior walls and ceilings, and all three are on the shelf at Renders World. The difference is the form they come in and the job they lead on:
| Skim | Comes as | Per coat | Leads on |
|---|---|---|---|
| Atlas Gipsar Plus | Powder, 20 kg bag, mixed with water | Up to 5 mm | Levelling, filling and finishing from one bag |
| Atlas GO! | Ready-mixed, 25 kg bucket | Up to 3 mm | A smooth top finish rolled straight from the bucket |
| Atlas GTA | Ready-mixed, 18 kg tub | Up to 3 mm | Taped plasterboard joints and thin finishing coats |
How Much to Order
Gipsar Plus uses about 0.8 kg per m² for each millimetre of thickness:
- Skim 1 mm thick — about 25 m² per 20 kg bag.
- Skim 2 mm thick — about 12.5 m² per bag.
A wall that needs levelling before the finish takes more. Orders are processed the same day when the stock is there, and the team quotes delivery after the order. You can also collect in person from the Renders World counter in Southampton during opening hours.
FAQ — Coverage, Coats and Use
How far does one bag go?
About 25 m² at 1 mm thick, or about 12.5 m² at 2 mm. Uneven walls that need levelling first take more.
How soon can the second coat go on?
After 1.5 hours. It can go on wet-on-wet or on a fully set first coat.
Can I apply it with a roller?
Yes. Atlas recommends a scotch-brite type pile roller, such as the Atlas Rollo Finish roller. Smooth the rolled coat with a stainless steel trowel straight away.
Can I use it on plasterboard?
Yes, for full-surface skimming to finishing levels Q2 to Q4. Tape and fill the joints first with a jointing compound such as Atlas GTA, then skim over the whole board.
Can I use it in a bathroom?
No. Gypsum skims are not for bathrooms, laundries or rooms that stay above 75 % humidity, or for walls exposed to direct moisture.