Hi all.

Been advised by a fire safety officer to install intumescent pipe collars on the cellar side of 2 4inch plastic air vent pipes that lead from a lower ground flat through a brick wall into the lower ground cellar.

Trouble is the pipes tee off on a right angle so tight to the wall on the cellar side there is no way to get the collars on a straight section of pipe (see pic).

Do I drill out the wall round the pipes to allow space to fit the collars then patch up with sand and cement or is there any easier solutions as I am loathe to do that and definitely do not want to replace the whole vent system it all as it was newly installed albeit before I got the place.

Thanks in advance Anthony

You first need to clean up the plaster work then measure the size of collar, depth, diameter and rating you require, then contact the experts like Envirograf at https://envirograf.com/product/intumescent-collar/ and get their advice.

FSI Ltd do a shallow neck collar that is only 25mm deep for this very application. 

Thanks Fellas!