Help! Mystery smell in our new house!

Kimlock

Thanks.

What would you suggest would be the best thing to do to make it air tight/ smell proof? The cement or the flexible filler? Bearing in mind that I am very much a novice at DIY!

brightontraveller

If the pipe is sleeved e.g. Smaller going through bigger and the bigger pipe protudes further out from the wall I’d sand and cement up to that externally and internally

That leaves you with the gap between gas pipe which goes through the sleeving pipe I would seal that gap internally with a external mastic/ silicone sealant etc
This may help better than my description
http://www.gas-news.co.uk/discus/messages/3480/1236.gif

Leaving the external pipe unblocked allowing for gas to escape should building movement etc damage the pipe through he wall that’s what the sleeving is there to prevent though ?

All can be bought cheaper just to give to you an idea of what too buy ,,,,
Materials
Sand and cement ready mixed
http://www.diy.com/departments/lafarge-ready-to-use-mortar-20kg/35726_BQ.prd

Silicone sealant
http://www.sealantsandtoolsdirect.co.uk/dow_corning_791_weatherproofing_low_mod_silicone_sealant_buff_P24864.html?gclid=CNKisvGBrcICFUcTwwodlqMALg
Depends how big is the hole ?

Others would just buy ready made filler and fill the lot internally externally
http://www.diy.com/departments/polycell-weatherproof-filler-175kg/189922_BQ.prd