Tell us the structure, the water condition and the access you have, and our technical team will write the build-up for your project.
• A wall is judged by what is put on it, and blamed for what happens to it afterwards.
• A crack that appears in paint two years later usually started as a movement the render could not take.
• A hollow patch under a tile was decided when the plaster was applied to a dusty surface. A wall that was two centimetres out of plumb costs that two centimetres in material across every square metre of the building.
” None of this is visible at the point where it is created, and all of it is visible later. Which is why the sequence on this page matters as much as the products in it: block, mortar, primer, render, skim, and the drying time between each of them. “
1 · Building the wall →
2 · Rendering large areas quickly →
3 · Bringing the surface to paint-ready →
When it is preferred:
The wall is being built. Two versions cover two ways of building it: brick and similar units laid in a conventional mortar bed, and aerated concrete blocks bonded in a thin bed.
The version is marked on the bag. Both are ordered under the same name, so the version has to be stated when specifying and when ordering.
• Foundation or slab level checked before the first course; every error here is carried up the wall
• The correct version confirmed against the units being laid, before the first bag is opened
• Units clean and free of dust
• Absorbent units dampened according to the weather, so they do not draw the water out of the mortar before it sets
• Only as much mortar mixed as can be laid within its working time
DAUFORM WALLMAKER is a cement-based, polymer-modified mortar with water-repellent properties, supplied in two versions.
The masonry version is laid as a conventional bed for brick and similar units. It holds its texture, which is what allows a unit to be set, tapped down and left in position rather than sliding under its own weight.
The aerated concrete version is a thin-bed adhesive, applied with a notched trowel in a few millimetres rather than a full mortar bed. That is what aerated concrete needs: a thick joint between two insulating blocks is a thermal bridge repeated across the whole elevation, and it undoes part of what the blocks were chosen for.
In both versions the polymer modification improves adhesion to the unit and keeps the mortar workable long enough to correct a course before it sets, which is where the level of the whole wall is decided. The water-repellent property works after the wall is built, in the joints, where a plain mortar would carry water into the wall by capillary action.
• Joints struck and cleaned before the mortar sets
• Wall protected from rain and frost until the mortar has gained strength
• Plaster applied only after the wall has settled and dried
Check the version before the first bag is opened. A thin-bed adhesive laid as a thick bed loses the coverage it was calculated for, and a masonry mortar used as a thin bed on aerated concrete does not hold. Both mistakes are made after the wall is half built.
The level of a wall is set in its first three courses and paid for in plaster. Two centimetres of error is two centimetres of extra render across the whole elevation, and no plaster system recovers that cost.
Key outcomes
• Two versions for two ways of building, ordered under one name
• Units that stay where they are set
• Thin joints on aerated concrete, so the wall keeps the insulation value the blocks were chosen for
• Water-repellent joints in the finished wall
• Declared under EN 998-2
Products
• DAUFORM WALLMAKER, masonry version · polymer-modified, water-repellent masonry mortar for brick and similar units, EN 998-2
• DAUFORM WALLMAKER, aerated concrete version · thin-bed adhesive for aerated concrete blocks, EN 998-2
Complementary · Optional
– DAUFORM RPM-S where a course has to be made good before plastering begins
• Surface sound and free of oil, grease, rust, paraffin and bitumen residue
• All loose material removed
• Porous and highly absorbent surfaces dampened
• DAUGUARD B-PRIMER applied to bare concrete surfaces before plastering, and allowed to dry
• Beads, stops and reference points set out before the machine starts
DAUFORM AUTOMATIC is formulated to be pumped, sprayed and ruled off. That changes the economics of a large elevation: the material arrives on the wall at a constant rate and a constant consistency, and the crew rules and floats rather than mixing and carrying.
The primer under it is not optional on concrete. Bare concrete is dense, low in absorption and often carries release agent from the formwork, and plaster applied straight onto it has nothing to key into. B-PRIMER is a quartz-filled dispersion; the filler gives the surface a texture the render can grip, which is the whole reason it is there.
• Surface ruled and floated within the working time
• Render protected from rain, wind and direct sun while it cures
• Skim or finish applied only after the render has dried back
Plaster on bare concrete without a primer is the most common hollow render on any site. Concrete does not absorb, and it usually carries release agent; the render has nothing to hold onto and sounds hollow when it is tapped a month later.
The second most common failure is the straight crack that follows the line where a concrete frame meets block infill. Two materials that expand at different rates share one render, and the render tears along the seam. Mesh embedded across that line does not stop the movement; it spreads it over a width instead of letting it concentrate in one crack.
Key outcomes
• Large elevations rendered at machine speed with consistent thickness
• A background that a finish can be applied to without further correction
• Declared under EN 998-1
Products
• DAUGUARD B-PRIMER · quartz-filled primer for bare concrete, applied before plaster
• DAUFORM AUTOMATIC · machine-applied cement-based plaster mortar, EN 998-1
• DAUMANT PRONET-160 · alkali-resistant glass mesh for reinforcement at material junctions
Complementary · Optional
– DAUMANT PRONET-160 · alkali-resistant glass mesh, embedded in the render wherever two different materials meet: concrete frame against block infill, lintels, and the corners of openings. These are the lines where the two materials move at different rates and where the render cracks if nothing distributes that movement.
– DAUFORM RPM-L where the background has to be levelled or repaired before plastering
• Render cured and dried back
• Surface free of dust and loose material
• Fine cracks and texture differences identified in raking light rather than in flat light
DAUFORM FP50 is a white cement-based skim. It goes on thin, closes the pores and the fine cracks left in a render, and evens out the difference in texture between old work, new work and repairs. Because it is white cement based, the surface it produces takes paint evenly instead of drawing it unevenly the way a grey render does.
Where the surface is highly absorbent, DAUGUARD D-PRIMER goes on before the paint or the decorative coating. An absorbent surface pulls the water out of the first coat before it can form a film, and the result is a patchy finish that gets blamed on the paint.
• Surface rubbed back once the skim has set
• Paint or decorative coating applied after the skim has dried, not when it looks dry
Check the surface in raking light before skimming and again before painting. A wall inspected under a lamp held flat against it shows what the wall will look like on the first sunny afternoon after the building is handed over.
Key outcomes
• A flat, even surface that takes paint uniformly
• Fine cracks and texture differences closed before the finish goes on
• Declared under EN 998-1
Products
• DAUFORM FP50 · white cement-based skim plaster, EN 998-1
• DAUGUARD D-PRIMER · filled acrylic primer for absorbent surfaces before paint and decorative coatings
Complementary · Optional
– DAUFORM RPM-S where the render has defects too deep for a skim to close