Old School Roof Space Ventilation

[Seb101]

We moved into an old school building (built circa 1880) that was converted by turning the each of the 2 high-roofed halls into 2-storey accomodation. The roof spaces have been left with the original timbers. At the end of each of the halls the gables have these old fashioned ventialtion openings as pictured below.

They have been left in various states accross the building. One is completely open, one is open but with a wire mesh over it, the other two have been stuffed full of loft insulation wool.

What is the correct way to leave these openings? I assume they need to be there to provide some level of roof space ventilation, but leaving them completely open means the wind howls through the roof spaces end to end and an awful lot of heat is lost, it also provides an opening for brids/rodents. At a minimum I think they should all have wire mesh over them, but is there also a best practice to insulating them against the elements while still ventilating the roof space?

Thanks.

 

[freddiemercurystwin]

Presumably your ceiling is a flat ceiling above the windows with adequate insulation sat on it? So the roof void should be vented, the vent should have a suitable grille (in keeping with the building) with an insect mesh covering the rear so that air can move through it freely but insects/birds cannot. A well ventilated roof space is a healthy roof space. That said is there felt beneath the slates? If there is no felt then the roof will likely be well ventilated irresepective of what you do with these vents.

 

[RandomGrinch]

it also provides an opening for brids/rodents

You may have to investigate if there are any bats hybernating up there, before blocking all the openings with mesh!

 

[Seb101]

Correct, there is a ceiling above the window line, leaving a small accessible loft space above, where these vents reside. The roof is felted, the tiles have been replaced with modern slates during the conversion. Adequate insulation however, there is not (this needs fixing in any case) and I'm less concerned about the heat loss than I am about the noise it creates when wind blows end to end through the building. Presumably this could be fixed by fitting louvres on these vents as well as a mesh?