Architects Undercoat Paint Finish

Architects Undercoat Paint Finish is the perfect base for water based Eggshell and Gloss paints where speed of application and low odour are the prime considerations. For use on pre-painted or bare wood and primed metals as the ideal preparation for all water-based finishes.

Finish Features

 – Available in 2.5 litres and 750ml
 – Covers up to 14 metres squared per litre
 – Environmentally friendly with minimal VOCs
 – Quick-drying, re-coatable in 4 hrs
 – Very low odour

Architects Matt Paint Finish

Surface Preparation Guide

New Wood
For soft woods, knots should be sealed with knotting compound to prevent staining. Resinous hard woods require cleaning and treatment with Little Greene Aluminium Wood Primer (consult the relevant product data sheet for further details) prior to undercoating.

Ensure moisture content of the timber is below 15% before commencing application. Damp wood should never be painted as this may give rise to blistering, flaking, cracking and premature coating failure. Green oak should not be painted unless it has been weathered for at least 6 months.

New ferrous metalwork should be hand, or mechanically cleaned, to remove any surface rust before application of Paint & Paper Library Oil Undercoat. Non ferrous metals must be pre-treated or primed with an appropriate proprietary primer.

Existing Paint Finish
Remove all loose and flaking paintwork. Degrease with a suitable detergent solution, such as sugar soap, followed by clean water rinse. Rub down thoroughly with a medium grade sand paper to provide a key and a defect free smooth surface, “feathering in” areas where paint has been removed. Make good any repairs, sand and apply primer to exposed surface as appropriate.

For long term performance, clean & lightly sand down surfaces. Prime using a proprietary adhesion promoting plastics primer before applying Paint & Paper Library Architects Undercoat.

New Plaster Walls
For plaster skim, allow at least four weeks for the plaster to thoroughly dry. Apply a primer coat by thinning the paint with a 5 to 25% (v/v) addition of clean water, depending upon the porosity of the substrate.

Cut in by brushing at the same dilution recommendation as for priming, to promote flow and sealing of the substrate. For new, fully plastered walls, allow at least six months for the plaster to thoroughly dry before painting. This product is not recommended for painting lime or other natural plasters.

Existing Plaster Walls
Lightly wash any existing paint work to remove any dust or surface laitance. Apply a primer coat by thinning with a 0 to 25% (v/v) addition of clean water, depending upon the porosity of the substrate. This product is not recommended for painting previously painted lime or other natural plasters.


Stir thoroughly before use. Do not apply to surfaces when the ambient temperature is below 5˚C or if there is a risk of rain during application or drying. To obtain good flow, apply generously but avoiding runs and sags.

Use a high quality synthetic bristle brush that is suitably sized for the project at hand. New brushes should be conditioned by washing in clean water and thoroughly drying with a clean, lint free, cloth. Avoid immersing brush too far into the paint to prevent paint from entering the ferrule.

Avoid drips and splashes by not overloading the brush. Apply paint in even strokes and only extend painting area such that a wet edge can be easily maintained. For the highest quality appearance, keep final brush strokes all in the same direction and never go over paint that has already begun to dry.

For intricate items, or where high ambient temperatures/high air flow conditions cannot be avoided, the open time maybe extended with a 10 to 15% (v/v) addition of a propriety water based paint conditioner. This advice is also applicable to large flat areas; however, use of a paint roller is the recommended application method in such cases.

Use a short nap wool blend type sleeve for best appearance on smooth surfaces. Increase nap length for textured surfaces, as appropriate, to ensure even and thorough coverage. Keep final strokes all in the same direction, maintaining a wet edge throughout.

Never be tempted to go over already drying paint as this will lead to lap marking and flashing. When high ambient temperatures/high air flow conditions cannot be avoided, the open time maybe extended with a 10 to 15% (v/v) addition of propriety water based paint conditioner.

Spray Finishing
Thin with up to: 40%(v/v) water
Tip size: 1.60 to 2.00 mm (62 to 78 thou)
Air pressure: 0.28 to 0.41 MPa (40 to 60 psi)

Thin with up to: 20%(v/v) water
Tip size: 0.28 to 0.54 mm (11 to 21 thou)
Pressure at tip: 12.6 to 19.6 MPa (1800 to 2800 psi)


Remove excess paint and clean all equipment using white spirit, or appropriate substitute, immediately after use.

Never store brushes or roller sleeves in cleaning solvent as this will result in deterioration of their application performance.

Storage & Shelf Life

Store unused paint in a cool, dry, frost free area, away from direct sunlight and sources of ignition. Ensure tin lids are securely and correctly replaced after use.

When unopened and stored under the conditions above, this product is stable for a minimum period of two years.


Disposal & Recycling
Dispose of excess or waste paint via a licensed waste handing operator.

Empty metal containers may be recycled (remove plastic handle on 2.5L and 5L tins).

Health & Safety
Always read the label on the can before use. Ensure maximum ventilation during application and drying.

Please consult the product material safety data sheet for further details.