Porotherm ZeroPlus Mortar

Porotherm ZeroPlus Mortar

15KG Bag

Porotherm ZeroPlus mortar is a thin-joint mortar for building with Porotherm from zero degrees – so you don’t have to stop in cold weather, saving time and money!

Specifically formulated for Porotherm

The ZeroPlus™ thin-joint mortar is specially formulated for the Porotherm construction system, enabling it to be laid at zero degrees Celsius on a rising scale.

ZeroPlus™ has been validated for use at 0oC by the UK testing house Lucideon. The innovative mixture has been designed to provide the same performance at between 0oC and 3oC as existing thin-joint and traditional mortar, which can only be used at temperatures of 3oC and above.


The innovation should reduce downtime and extend build programmes longer through the winter months than ever before. It is estimated this could extend working time overall by up to two weeks in a typical winter, helping to maintain build programmes and secure employment for bricklayers over the period.

Unlike existing thin-joint and conventional mortars that are for use at 3°C and above, ZeroPlus™ mortar is designed to work at temperatures from 0°C and rising. Wienerberger has developed ZeroPlus™ to work exclusively with the Porotherm clay block walling system.

Maximising build time in winter – earlier starts on cold days

Extra build time in winter – up to 2 weeks additional build time

Reducing downtime – reduced risk of stoppages for building contractors

Proven performance – validated by Lucideon as comparable to existing Porotherm mortar

Supplied free – with the Porotherm clay block walling system

ZeroPlus™ and Porotherm, helping Ireland to build up to 4x faster all year round

Technical Information

Storage and processing Instructions

Download pdf guide here

Available as 15kg bag


For a full bag mix add approximately 3.6 litres of clean water to the bucket then add the powder. Stir quickly and vigorously (using an agitator / paddle mixer) until a smooth, lump free consistency is produced. Allow to stand for 10 to 15 minutes and then stir again. The mixed mortar is transferred from the bucket into the special Porotherm mortar roller. Mortar is normally applied to a 5 to 6m length of horizontal joint using the mortar roller. The speed of rolling and the angle of application must be adjusted to ensure that an even mortar layer is applied evenly from the roller and covers the entire surface area of the horizontal joint.


Processing time: Protected mortar; approximately 4 hours at 20°C, but will be extended at lower ambient temperatures and reduced at higher ambient temperatures.

Processing temperature: Use only when the air temperature is at least 0°C and rising. Please be aware that internal situations may be colder than external and any wind chill factor must be taken into consideration. Do not use when blocks or existing work are frozen.


Do not mix with water that is partially frozen or is thawing. Mixing water should always be from a mains tap that has not been frozen. In addition, early strength development will be reduced at low temperatures and therefore the blocks and mortar must be adequately protected at all times, with appropriate insulating covers prior to and after application, so that fresh masonry does not fall below 0°C. Mixing in an insulated bucket with an insulated lid is strongly recommended.


This product contains cement and produces an alkaline reaction when it comes into contact with moisture/water. Therefore, ensure that skin and eyes are protected. If it should come into contact with the skin or eyes, rinse them thoroughly with water. Seek medical assistance immediately if it comes into contact with the eyes. Contains Chromium VI, however a reducing agent ensures that the Cr VI content of the mortar remains below 2ppm during the shelf life of the product. It may produce an allergic reaction. For full information please refer to the Material Safety Data Sheet.


There are no reviews yet.

Be the first to review “Porotherm ZeroPlus Mortar”


Go to Top