I’m having a lean-to conservatory built at the rear of an Edwardian terraced house. Nothing fancy, just a roof, concrete floor and dwarf wall with glazed frontage. The sides to be existing fire-break and house walls. The surveyor has completed his drawings and sent them for my approval.
He has drawn in an extension (I believe this is usually done with a 4” pipe embedded in the new concrete floor) to the airbrick (no 1) so that it emerges in the open air. This newish airbrick was lowered when an exit door was installed some years ago, and is 2cms from the floor, 4cms in height and the standard 8” wide. However, he stated that the same procedure would ‘not be possible’ with the other existing airbrick (no 2) as it was the Edwardian original, 2” from the floor and 3” in height – again it is 8” wide. He said because it was higher - total from floor to top of brick 5” as against 2.36”, the airbrick would have to be vented into the conservatory: a closed space with no appreciable external airflow.
I was always taught that the airbricks front and rear of a terraced property needed to be open to the elements so that whichever way the wind blew it would ventilate the underside of the timber flooring. This will not happen if one side is enclosed and seems to be a recipe for damp and wood rot.
Is there a remedy for this problem that I can discuss with the builder when he arrives to do the surveyor’s instructions? Can not the air flow through the ‘higher’ (no 2)airbrick be directed via a cowl or special ‘Z’ shaped plastic fitting onto a lower level and thence through the 4” pipe arrangement into the outside air? Admittedly airflow will be somewhat constricted by the 90 degree turns, but surely much better than just ending up in stationary air?
He has drawn in an extension (I believe this is usually done with a 4” pipe embedded in the new concrete floor) to the airbrick (no 1) so that it emerges in the open air. This newish airbrick was lowered when an exit door was installed some years ago, and is 2cms from the floor, 4cms in height and the standard 8” wide. However, he stated that the same procedure would ‘not be possible’ with the other existing airbrick (no 2) as it was the Edwardian original, 2” from the floor and 3” in height – again it is 8” wide. He said because it was higher - total from floor to top of brick 5” as against 2.36”, the airbrick would have to be vented into the conservatory: a closed space with no appreciable external airflow.
I was always taught that the airbricks front and rear of a terraced property needed to be open to the elements so that whichever way the wind blew it would ventilate the underside of the timber flooring. This will not happen if one side is enclosed and seems to be a recipe for damp and wood rot.
Is there a remedy for this problem that I can discuss with the builder when he arrives to do the surveyor’s instructions? Can not the air flow through the ‘higher’ (no 2)airbrick be directed via a cowl or special ‘Z’ shaped plastic fitting onto a lower level and thence through the 4” pipe arrangement into the outside air? Admittedly airflow will be somewhat constricted by the 90 degree turns, but surely much better than just ending up in stationary air?
