Building admixtures can be found on building sites across the country providing numerous benefits to the workability of mortar, concrete, screeds and render, becoming especially useful during winter months when temperatures drop and working with these materials becomes increasingly difficult. Accelerators and air entraining plasticisers are the two most common types of admixtures available offering many benefits not only during the winter months but all year round.
As the name suggests, accelerators increase the setting and hardening times of mortar, concrete, screed and render and help offset the effect low temperatures have on these types of applications to provide faster finishing times, even in cold weather. 203 Accelerator and Frostproofer provides frost protection to the wet mortar during the setting period; even in sub-zero temperatures down to -8°C and can also be used as a plugging aid when mixed neat with fresh cement.
Where can 203 Accelerator and Frostproofer be used?
• In mortars
• Flooring screeds
• External and internal cement based rendering
• Non-structural concrete
• As an emergency repair plugging aid when mixed neat with cement
201 Mortar Admix replaces lime in the mix to reduce the chance of efflorescence and smooths out variations between separate batches of sand and cement. Air entraining plasticisers are used all year round and form small, extremely stable air bubbles within the mix, giving it a “buttery” consistency which is easy to work with and prevents shrinkage, cracking and crazing during the setting process. These air bubbles also provide a degree of frost-resistance during the setting process as well as giving continued resistance to freeze/thaw cycles. Whilst these air bubbles improve the workability of the mix, they do reduce its stability so shouldn’t be used for structural concretes or flooring screeds.
Where can 201 Mortar Admix be used?
• Load bearing brickwork
• Block laying
• External/Internal rendering
• Pointing/repointing brickwork
The benefits of these admixtures can be found together in 207 Zeromix CFF and Sika Wintermix, both of which are classic examples of products which incorporate the fast setting times of an accelerator for use in sub-zero temperatures with the improved workability of an air entraining plasticiser. These chloride free liquids improve freeze/thaw resistance and also eliminates the need for a separate frostproofer.
Admixtures are also available in concentrated formulations such as Sika MaxMix Frostproofer and Accelerator which will treat 100kg of cement with just 1L. Not only does this mean that less product needs to be carried but the amount of waste packaging is also greatly reduced; a topic which is currently high on the agenda.
Working in winter can often be a difficult time for the trade but by simply using the correct products for the time of year, work can continue even when the snow starts to fall.