I've always been puzzled as to where the soil stacks vented in our 2001 build detached house as all stacks are internal, but no external pipe protruding from the roof or vent tiles on the roof. I have just been in the loft and stumbled upon an open 100mm elbow which I believe is the vent for the soil stack from one side of the house, servicing the downstairs loo and
1st floor bathroom. There is another stack on the other side of the house for the utility and en-suite, so I reckon this is the same.I noticed also that the loft space wasn't that cold considering the outside temp of the last couple of weeks, but it has pretty good levels of loft insulation. And also, there has been an unknown smell in the loft at times. Not necessarily a bad smell, but an unexpected one nonetheless. Perhaps familiar with stagnant water or suchlike.
Is it a good idea just to have an open ended vent on the soil stacks (being just 90deg elbows) into the loft?
Will the open vent contribute to heating the loft space and is it really a good idea for it to be heating the loft right now (am I losing heat from the house?)?
Will it cause any problems if I remove the elbows and replace with air admittance valves?
Cheers