subloor block and beam airbricks

[suzanne1]

Hi . Hoping someone can offer advice. 1990s bungalow with subfloor airbricks (red plastic) on opposing sides front and back (longer lengths of build). One airbrick towards corner  of back elevation is blocked off due to previous owners add on conservatory just being concrete base and this airbrick had been venting directly into conservatory. An additional airbrick  (terracata brick type) has been added to this end of side elevation 500mm from corner with no opposing airbrick. Noted to have a DIYliner (? like insulation sheet used for packing) through cavity wall.This appears to go straight into void. All airbricks sit 2 bricks levels above ground level. No idea if other airbricks go straight through or are periscope type due to  integral mesh and brick work being double thickness at this level. Bungalow handed down through family since purchase  and original surveyours report was from a while ago with no mention of side wall airbrick though we also know he missed mentioning the fact that there was an airbrick venting into conservatory. This was all only realised sometime ater after purchase.We do know the side elevation aribrick wasnt there when mineral wool cavity wall insulation was added previously. A neighbour mentioned some white powdery dry sustance escaping when airbrick was being positioned but subsequently we ascertained this was not any of the cavity wall insulation as had that checked. Building control just said always good to ventilate void but didnt elaborate when we rang them. We could see through airbrick concerned that there is just one massive void under bungalow. Do we leave/cover/remove this particular airbrick and liner or just cover in winter or not at all. One identical build in a similar positioned property on estate has airbircks to side elevations only and none to front and back All others have front and back only regardless of direction they face.None have had a conservatory added and we know ours was allowed by council who had stated didnt need planning permission as has no heating to it and was within required measurements. There is a letter from original buidling company to say they had no issue with addition of a conservatory providing council had no issues either.

Edited January 26, 2021 by suzanne1
further info added

[Russell griffiths]

It is probably wise to not have one in the conservatory, draughty and could vent ground odour or gasses into conservatory. 

Look for an alternative position and cut one in if you think it’s needed. 

The idea is to have adequate airflow under the floor to prevent a damp stale environment, good airflow will not stop it being damp but will prevent it getting out of hand a keep it a bit fresher. 

[suzanne1]

Thanks. So the subfloor airbrick subsequently fitted to the side elevation of the  bungalow would be acceptable as an alternative in order vent the subfloor and leave the one blocked which exits into the conservatory ? I was worried  this aditional  airbrick would  create a cold spot  under the subfloor?  I am also worried that it is not adhering to the airbricks on 2 oposing sides rule as this is on a side elevation  with no opposing one and is in addition to the subfloor airbricks on 2 opposing walls as indicated for blcok and beam flooring. Do we also need to inform insurance ot this additional airbrick being fitted as when we took out a house insurance policy they asked if there were any additional airbricks adde and we said no.  We have no morgage so the insurance was not needed to cover a morgage.

 

 

Edited January 27, 2021 by suzanne1
correct wording

[suzanne1]

On 26/01/2021 at 10:18, Russell griffiths said:

It is probably wise to not have one in the conservatory, draughty and could vent ground odour or gasses into conservatory. 

Look for an alternative position and cut one in if you think it’s needed. 

The idea is to have adequate airflow under the floor to prevent a damp stale environment, good airflow will not stop it being damp but will prevent it getting out of hand a keep it a bit fresher. 

 

On 26/01/2021 at 10:18, Russell griffiths said:

It is probably wise to not have one in the conservatory, draughty and could vent ground odour or gasses into conservatory. 

Look for an alternative position and cut one in if you think it’s needed. 

The idea is to have adequate airflow under the floor to prevent a damp stale environment, good airflow will not stop it being damp but will prevent it getting out of hand a keep it a bit fresher. 

 

On 27/01/2021 at 07:49, suzanne1 said:

Thanks. So the subfloor airbrick subsequently fitted to the side elevation of the  bungalow would be acceptable as an alternative in order vent the subfloor and leave the one blocked which exits into the conservatory ? I was worried  this aditional  airbrick would  create a cold spot  under the subfloor?  I am also worried that it is not adhering to the airbricks on 2 oposing sides rule as this is on a side elevation  with no opposing one and is in addition to the subfloor airbricks on 2 opposing walls as indicated for blcok and beam flooring. Do we also need to inform insurance ot this additional airbrick being fitted as when we took out a house insurance policy they asked if there were any additional airbricks adde and we said no.  We have no morgage so the insurance was not needed to cover a morgage.