Recycled Paper Fire Bricks

[NorthernRaider]

An old geezer out our back makes these blocks as well to burn in his grate, he made a frame from some discared old but not broken double glazing panels in his garden to act like a solar kiln to dry his fire blocks out on, clever old bugger.

[Tarrel]

Treat them like firewood. i.e. make them now, dry them out over the summer, ready for use next season.

[Timelord]

DeJaVue thread.
The effort required to process the ingredients, make the brickquettes, the drying time and the cumulative handling time makes these an inefficient heat return for the labour expended. A much greater heat return per unit of labour would be returned from sourcing decent wood.