Showing 0 products
Frequently Asked Questions
How is CEM II different?
Portland cement with a moderate blend.
Limestone, fly ash, slag or calcined clay.
Blended at the cement works.
The proportions are moderate.
It is a family of cements, not one product.
Is this what I am usually buying?
In most markets, yes.
General-purpose bagged cement is now CEM II.
The change happened gradually.
Many buyers have not noticed.
The label states the actual type.
Does it behave differently on site?
For most work, no.
It mixes, places and finishes the same.
Foundations, slabs, mortar, render, screed.
No adjustment is normally needed.
The differences appear at the edges.
So what does it buy?
A materially lower carbon footprint.
Clinker is where nearly all the carbon sits.
Replacing some of it reduces that directly.
At effectively no practical cost.
That is why it became the default.
Where does the difference show?
In early strength, slightly.
It lags CEM I at a few days.
Cold conditions widen the gap.
Winter work needing early strength notices.
A higher strength class can compensate.
Does colour vary?
Yes, with the constituent used.
Limestone blends are typically paler.
Slag blends are paler still.
It only matters on exposed work.
Check before an as-struck finish.
Why read the full designation?
Because CEM II is a family.
A letter and number follow the type.
They identify constituent and proportion.
A limestone and a slag blend differ.
In cold weather and in aggressive ground.