Air Bricks placed in the middle of a wall, Lintels Need Replacing, Cavity Wall Insulation

[San47]

Hi,

I am looking for some advice.

I am going to buy a 1960/70s bungalow and the survey has come back with some concerns:-

Firstly, the surveyor does not know why one of the owers have put air bricks so high up. Other concerns is 2 lintels need replace and the cavity wall insulation could possible be urea formaldehyde insulation, also the gable end need repointing. My question is are these jobs massive and going to be too much, or they arent anything to be too concerned about, also, why put the air bricks so high up? Pictures below:-

 

[stuart45]

Do the air bricks go through the wall to the inside, or are they just into the cavity?

 

[Cubist]

I'm assuming the interior floors are all concrete and, as there would certainly be a damp course, the only reason for the air-bricks, particularly if they are not visible indoors, is to ventilate the cavity walls. However, there was/is a a desire among some to install cavity wall insulation and if done this would render the air-bricks redundant. If, the walls have been treated in this way its a fairly minor job to replace the air-bricks with standard bricks to match the building.

Regarding the lintels; after 60 years some corrosion on the leading edge of the steel is only to be expected. Provided that there is only minor surface rustit can be cleaned back and the edge protected with a suitable paint. It's worth checking to see if heavy rusting of the steel is disrupting the mortar immediately above it as this may indicate that the lintel may be weakened. Any need to replace the lintels would only arise if the rusting is heavy and extensive so look for 'scabbing' and material loss/holes.

 

[stuart45]

There's a fair chance that there are no lintels on the external skin. Back then it was common practice to have a 6x6 concrete lintel on the inner skin, and run the brickwork on top of the timber window frames.
The problems start when the timber are replaced with plastic.

 

[San47]

Thank you both for replying,

Do the air bricks go through the wall to the inside, or are they just into the cavity?

There are vents on the inside of the property

 

[Stevers]

The vents could have been added because there are gas appliances in those rooms, or perhaps something else that needs more air than can come from gaps round doors, windows and floors.

 

[Cubist]

Are the rooms the vents are sited in kitchens and bathrooms by any chance?

Seems overkill to me but the builder may have been belt and bracing - and the draughts indoors will be just as bracing perhaps.

 

[Stevers]

My father introduced a through vent to his kitchen for the near fridge sized Ideal Standard floor mounted gas boiler fitted in around 1970 and still going strong. I can't say that I've ever noticed the resulting draughts in the room which always seems nice and cosy!

 

[paulc]

My father introduced a through vent to his kitchen for the near fridge sized Ideal Standard floor mounted gas boiler fitted in around 1970 and still going strong. I can't say that I've ever noticed the resulting draughts in the room which always seems nice and cosy!

British Gas punched a massive hole through the dining room wall here (some 9" x 6") to provide air for a Baxi back boiler. Could never get the room up to a decent temperature after that.... Replacing the boiler shortly, so I can finally brick up that hole and seal off yet another source of cold draughts.

 

[San47]

Are the rooms the vents are sited in kitchens and bathrooms by any chance?

Seems overkill to me but the builder may have been belt and bracing - and the draughts indoors will be just as bracing perhaps.

No, the vents are located in 2 bedrooms

 

[Cubist]

No, the vents are located in 2 bedrooms

Then my first comment stands - overkill.

Air-bricks are/were most frequently used to introduce airflow beneath suspended wooden floors to combat rot. Sometimes they were also located high uo in the external walls of upper floors and beneath the ceilings below attics to encourage the exit of warmed and moisture laden air from the property.

IMO, at about two feet above external ground level those air-bricks are kind of useless unless the aim was to encourage air flow into those rooms or perhaps expel the typical odours produced by a couple of teenagers.

 

[stuart45]

I used to have a bungalow with teenage daughters, and found their bedrooms suffered from condensation issues more than the bathroom or kitchen. It's probably that they spent so much time in there, as well as having a few friends in all evening.

 

[fernicarry]

There are vents on the inside of the property

My parents house was a similar 1970's construction (but two storey semi) and had vents at about head height in the bedrooms. My mum used to tape plastic bags over them, then complain to the double glazing company about the condensation on the windows...

It was always freezing cold in that house no matter what you did but I suppose that prepared me for life in my current home.

It also had the same lintel problem on the side window. A local builder fixed it for a few hundred quid. Cannot say whether what he did was remotely structurally correct but it looked nice...

 

[stuart45]

They used to cut out a few courses of brickwork and stick a piece of angle iron in, but nowadays something like a Catnic L10 would be used.
The big window could be around £1,500.