brick laying in cold weather

Hello,

I am assisting a bricklayer in rebuilding a chimney and am wondering weather we should attempt it at all in this cold spell.

We are covering the work with an electric blanket at night, mortar fleece, tarps, etc. but I am concerned about the affect the cold will have on the mortar mix.

Any advice, positive or negative, would be gratefully received.

Woodburner

 

Hi Lee,

Got this off the web...

Brickwork which is damaged by frost is usually attributed to unsuitable mortar, wet bricks or bricklaying in freezing temperatures, it is unwise to lay bricks when the temperature is at or below 3oC. Make sure when laying bricks that the temperature is at least 4oC and rising when laid and afterwards keep the work covered for 48 hours, or longer if it is snowing, to keep it above freezing.

Water in the mortar expands on freezing disrupting the bond and causes cracks to appear in the joints.
Likewise if you use wet bricks the frost can cause the face of the bricks and mortar to flake. The end result is a loss of strength in the wall.

Cement sets more slowly in cold weather (roughly half as fast for every 10oC fall). If it rains when the
mortar hasn’t set, the rain can wash out the mortar from the joints and discolour the rest of the brickwork.

All of these eventualities can be overcome by a bit of forethought in using a mortar mix suitable for cold
weather and by keeping all materials, working areas and completed work covered up.