Blocking off a chimney

[Brian]

Hi I'm Brian.

I am renovating a kitchen in a recently acquired 3rd floor flat and need to fit a gas cooker into a defunct chimney breast. Questions:

1. What material is best to seal off the opening immediately above the burners of the cooker? The Corgi fitter will not certify the work unless the material used is fire resistant.

2. The chimney was previously used for a cooker but the blocking plate used looks and feels like asbestos based material.

I would be grateful for any suggestions.

Thank in advance

[jonlee]

best to use aspestalux fire board can pick it up at your local builders merchant or failing that aluminuim plate and stove rope around the edges