Can I cover exposed internal gas pipes with pipe sleeves

As above as in any copper/metal gas or water pipes need to be sleeved if going through a brick or concrete wall internal or external. Also it gas pipes need to be insulated if in cold or hot conditions as temperature effects the gas pressures coming from the main especially in cold conditions.

Any gas pipe that goes through internal walls must be sleeved. Any gas pipe running internally and is visible only required correct support clipping. Does not require sleeving.

I take it by reading description it is an exposed gas pipe you want to cover with shiny chrome covers the answer is no gas pipes can be boxed in but must be ventilated at either end of boxing to allow any gas leaking to escape

Hi Gas pipe passing through the external or internal wall has to be sleeved and filled with fire proof silicone from the inside. However, the exposed gas pipe mechanical protection is a good practise. There is no law stating that the gas pipe has to be insulated from the outside. Cold weather will not do anything ,however extremely hot weather will slightly increase standing pressure.