Ventilation for Cavity Wall Insulation Causing Draughts

super_freddie

Hi,

A family member has recently had cavity wall insulation carried out and was told that in order to limit moisture and other issues in the various room in the house, there is a requirement for ventilation holes in each room. I've checked online and this appears to be correct. In addition, the installer stated that there were differing requirements for the air vent, depending on whether there was a fire / oven in the room or not: if there was no fire, the vent could have a closable cover (although even when closed the cover is not airtight) but for rooms that had a fire / oven, the vent could only be covered with a plastic cover that consisted of a number of horizontal plastic bars that could not be fully closed, therefore no thermal insulation whatsoever is provided.

The above ventilation arrangement has resulted in severe draughts in a number of the rooms, particularly where there are no covers on the vents (i.e. the rooms with a fire / oven). When the vents were being installed in the relevant walls, the only advice that was given in the event of the above draughts occcurring was to stuff the ventilation holes with paper / cloth. This seems like a very unsatisfactory solution.

So my questions are:
(i) If there is a draught - does this mean that the vents were installed incorrectly or in the wrong wall?

(ii) Is the statement about differing vent requirements depending on the presence of a fire / oven in the room correct?

(iii) What are the options now to fix this problem? It would appear to me that using paper / cloth to stuff the hole and thereby prevent draughts is not only a sloppy way to attempt to fix the problem but also probably results in the room breaching the ventilation regulations.

Thanks,
super_freddie.

Robbie.G

super_freddie wrote: »

Hi,

A family member has recently had cavity wall insulation carried out and was told that in order to limit moisture and other issues in the various room in the house, there is a requirement for ventilation holes in each room. I've checked online and this appears to be correct. In addition, the installer stated that there were differing requirements for the air vent, depending on whether there was a fire / oven in the room or not: if there was no fire, the vent could have a closable cover (although even when closed the cover is not airtight) but for rooms that had a fire / oven, the vent could only be covered with a plastic cover that consisted of a number of horizontal plastic bars that could not be fully closed, therefore no thermal insulation whatsoever is provided.

The above ventilation arrangement has resulted in severe draughts in a number of the rooms, particularly where there are no covers on the vents (i.e. the rooms with a fire / oven). When the vents were being installed in the relevant walls, the only advice that was given in the event of the above draughts occcurring was to stuff the ventilation holes with paper / cloth. This seems like a very unsatisfactory solution.

So my questions are:
(i) If there is a draught - does this mean that the vents were installed incorrectly or in the wrong wall?

(ii) Is the statement about differing vent requirements depending on the presence of a fire / oven in the room correct?

(iii) What are the options now to fix this problem? It would appear to me that using paper / cloth to stuff the hole and thereby prevent draughts is not only a sloppy way to attempt to fix the problem but also probably results in the room breaching the ventilation regulations.

Thanks,
super_freddie.

1 it basically depends on what way the wind is blowing.I know the way that sounds but you can't control wind.
2 A room with an fire, cooker etc needs to have a fixed open vent
3 you can get snorkel type vent covers for outside that don't let wind blow directly through them
Been told to stuff the vents counter acts why they were put there In the first place

super_freddie

Robbie.G wrote: »

1 it basically depends on what way the wind is blowing.I know the way that sounds but you can't control wind.
2 A room with an fire, cooker etc needs to have a fixed open vent
3 you can get snorkel type vent covers for outside that don't let wind blow directly through them
Been told to stuff the vents counter acts why they were put there In the first place

Thanks Robbie. Sounds to me like these snorkel type vents should have been installed in the first place? Is this something that we should just get the original installers to do or could it be done as a DIY job? If DIY is an option, what is a good place to buy / brand? Not sure if answering this is in breach of any boards.ie etiquette (by promoting a company etc) - if so, PM'ing me the info would be apprecated.

Thanks again
super_freddie.

Irish Steve

Just a thought in passing. Ok, the vent has to be open if there is a fire or other combustion device in the room. If the device is not in use, it would make a lot of sense to me to put a chimney balloon or similar in the flue, for a vent to be draughty, the air coming in has to be getting out somewhere else in the room. OK, chimney is suspect No 1 , but it might be worth spending some time on checking out the airflow to see where it's going.

A cover externally will help prevent direct impact draught, but it's more likely the chimney that's causing it, If the device is lit, you need the air, if it's not, you don't need the chimney open.

Robbie.G

super_freddie wrote: »

Thanks Robbie. Sounds to me like these snorkel type vents should have been installed in the first place? Is this something that we should just get the original installers to do or could it be done as a DIY job? If DIY is an option, what is a good place to buy / brand? Not sure if answering this is in breach of any boards.ie etiquette (by promoting a company etc) - if so, PM'ing me the info would be apprecated.

Thanks again
super_freddie.

They wouldn't nessesary be fitted in all cases you could say it to your installer and see what they say or what remedies they come up with
If not the vent covers your looking for are anti draught covers and should be available
In any builders merchants