I am currently gutting my en-suite and have found the soil pipe behind a stud wall rising into the loft. Is it possible to cut the soil pipe right down to floor board level thus opening up the wasted space from the stud wall. There is already some type of air valve on but this is in the loft, could i fit the one advertised in screwfix (i.e.no escape of foul gases) and still be within building regs guide lines Thanks for any advice
im not 100% but I think that it has to be at minimum above the flood line of what its connected to !I E : water height in cistern, if thats the highest point and only connected to bog ? although, its arguable that the U bend is, but think any BCO will say flood at cistern level.
iprwolf is correct, the air admittance valve (sometimes called a Durgo which is a trade name) has to be higher than the flood level of any appliance connected to the soil pipe, usually the basin overflow. HTH
So If I understand you correctly you are saying that there must be at least one other standard vent pipe in the property. I have always believed this to be the case also.
I also believe so, BCO said so, and so thats what I must do, I thought I could get away without coming through extension roof, but MUST be vented, I Know, not what it says on the valve, but thems the rules !!!!!