How to seal these vents in my house?

[Flashman13]

Hi everyone, 

I have approximately 10 of these vents (picture below) throughout my house and I am looking to seal them to greatly improve the heat retention within my house.

My local store suggested using these plaster patches (https://www.bunnings.com.au/pfeiffer-15cm-plaster-repair-wall-patch_p1660009)  with a putty/crack filler to apply and cover them.

Would that be the best/easiest option to cover and seal these vents?

Is there any reason why I shouldn't cover/seal these vents?

Example: Not my vent - found on google 

[JacobZ]

Hi @Flashman13,

Welcome to the Bunnings Workshop community and thank you for your question.

Typically, vents are there for a reason, and if you aren't sure what that reason is, I would suggest you probably don't cover them without further investigation.

The vents could be there to help ventilate areas that are prone to moisture, and by covering them, it is possible that it would do more harm than good by sealing in moisture, which can lead to mould and other moisture-related issues.

Can I trouble you to share some photos of the actual vents in your house so our members can better assess the issue?

Also, how old is your house, and do you know if you have insulation in the walls?

If the walls are insulated and the vent leads into an insulated wall or ceiling cavity, then covering the vent may not make a significant difference to heat retention. The insulation should already be doing the heavy lifting in limiting heat transfer between the room and the cavity space.

If you are certain that covering them would not have a negative effect, then the Pfeiffer 15cm Plaster Repair Wall Patch with some Less Mess Multi-Purpose Joint Compound would be a good option, assuming it is large enough to cover.

Allow me to tag our experienced members @Dave-1 and @Nailbag for their thoughts.

Jacob

[Dave-1]

Good Evening @Flashman13 

I would hestiate to cover them totally, Ive seen this topic pop up over the past few years. 

How to cover wall air vents? Plus there are others.

Have a stroll through them as the reasoning is interesting. I have had my air vents in the bathroom painted over and yeah its caused issues. My bedrooms I suspect have had the same thing done and I do get moisture build up during winter.  

I like @EricL 's suggesting in the link above, where the modification can be closed off. That way you get the best of both worlds.

Dave

[AlanM52]

Hi @Flashman13,

@JacobZ has asked all the right questions and provided useful additional info.

1. I would not cover those vents.

2. Covering them will not greatly increase heat retention.

I suggest you cut A4 paper to size and tape across the corners to stick on each vent.

Then wait and see...

With the heat thing I doubt you will notice any changes.

Also monitor the wet/damp/humidity areas 

Cheers

[Nailbag]

Hi @Flashman13 

As others have mentioned, these vents should not be covered, especially during winter. they provide both internal and external wall ventilation to prevent harmful mould forming. The only hesitant advice I can offer is to temporarily cover say 1/2 of any vents that are causing the most drafts with A4 paper and tape.

Nailbag

[R4addZ]

Hi @Flashman13 

Another reason these vents were fitted in many homes is the fact that you can buy unflued gas heaters and if there is no ventilation, you can be exposed to high carbon monoxide levels which could be fatal. On my last build, I requested a gas bayonet in the family room and was knocked back as the house was designed around new energy efficiency requirements and so did not have any vents.