Seen the mention of Primer so thought I'd leave this here, very popular product...
Thermal Primer - 1 Litre (10m2) - http://www.uheat.co.uk/thermal-primer-1-litre-10m2/
Thermal Primer - 1 Litre (10m2) - http://www.uheat.co.uk/thermal-primer-1-litre-10m2/