Materials you will need: burlap, cardstock, ruler, X-Acto knife, computer, inkjet printer. 1  Measure out your piece of burlap to 8.5 by 11. Use the X-Acto knife to cut it. 2  Repeat with the card stock. 3  Use the masking tape to affix the burlap to the card stock. 4  Make sure your printer settings are set to Heavy Duty.
Ideally, concrete should be poured when the air temperature is between 50 and 90 degrees Fahrenheit. Cold temperatures slow the concrete-setting process, and when temperatures dip below freezing, the delay allows the water in the mix to freeze before the concrete hardens.
The now withdrawn design code BS 8110 required that the temperature of the concrete does not fall below 5 O C at any point until the strength has reached 5MPa. The workmanship clauses are now in BS EN 13670 Execution of concrete rather than the desing codes and follow the same requirement. Surfaces that will be in contact with the newly placed concrete, including sub-grade materials, need to be a few degrees above freezing (2 O C). Reinforcing bars (and other embedded metal) must be free of ice and snow but otherwise there is generally no restriction on their temperature prior to casting.