What do airbricks do? Is my house solid wall?

abankerbutnotafatcat

I've recently purchased a property that is both my first house (as opposed to flat) and my first period property (1901), so I'm learning!!!

One of my first lessons was how important the twins of good drainage and ventilation are.

In the bathoom is an airvent which feeds straight through the wall to the outside. That I get.

However, I can see airbricks in other places that do not show on the inside. As i'm presuming a 1901 property is solid wall I'm wondering where does the air brick ventilate to/from???

Sorry if this is a stupid question!!

On a slight aside, I've been on the Energy Saving Trust site a bit following links on solid wall insulation from other threads. It says you can identify what type of wall your house has by the brickwork. My house seems to have both types - half of wall in one and the other half in the other. Is this normal and what does it mean?

Cavity Wall

Solid Wall

ormus

cavity walls were pretty universal by about the 1920s.
for house building 50 yrs prior to that, it was hit and miss if you have a cavity wall or not.
small/cheap houses rarely did.

easiest way to check for sure, is to remove the air vent. and inspect.

spannerzone

If you can see the bricks (ie not a rendered outside wall) then you can tell if it's solid by the way the bricks are laid, if you see bricks in the style of the second picture above then it's solid (you see side 'stretcher' and end 'header' of the bricks), if you can see the brick side 'stretcher' only as in pic 1 then it's a cavity wall.

On a solid walled house the airbricks are usually there to provide airflow under the wooden floors.... in my old solid walled house the wooden floors were about 2 feet above the ground / soil level and so the airbricks which were just below floorboard level ensured good airflow under there so no damp or dry rot could occur and rot the floor/supporting joists etc.

It's essential you do not block the vents or reduce airflow otherwise you get all sorts of issues with dry rot, damp and other problems as far as I can see. On my house the builder I had in to tend to some damp issues fitted 2 more airbricks on the side wall of the house (it was an end of terrace) to increase airflow as previously it relied on just one airbrick front and back.

Also any bricked up chimneys should have an airvent in them so ventilation isn't reduced and that can cause damp issues.

abankerbutnotafatcat

My house seems to have both types. Was that usual? It is a 3 storey semi townhouse with the bottom floor approx 7 ft and the 2 upper floor approx 8ft ceilings. The front and back are of the solid wall brick formation but the side wall has solid wall type bricks from the ground to 6ft high and then the cavity wall type bricks from 6ft off the ground to the roof.

shaney310879

i have a house with cavity walls and its been suffering from mould and condensation. I have fitted vents in the bathroom, kitchen etc to allow steam etc to leave the house. I have also been advised to fit air bricks around property. How will this help because surely all its doing is venting the cavity!?!

Radshire

You could try a more modern solution.
Enviro Vent provide solutions for all sorts of damp / condensation issues. They're pricey mind (I paid over £1k for my loft mounted unit, extractor and installation), but I was happy.

http://www.homeventilation.co.uk/whole-house-ventilation.php

Basically, I had a house which I used to live in, and then rented it out. Whilst I was there, and probably because it was my house, I made sure that the windows were opened, that air circulated etc. However, when tennants moved in, their complaint was that the place was damp. They were quite right too - I had to repaint bedrooms and the kitchen after every tennancy.

I chatted to my lettings agent who then advised me of this company who provided different solutions. I had a quote, and they came and installed the unit in a couple of days. They also shaved off a little from the underside of the bedroom doors to ensure that the air circulated in the rooms.

Basically, what mine did was to circulate air throughout the house using a small unit mounted on the upstairs landing ceiling. There was a small condenser in the loft which worked to evaporate the moisture out of the house.

I didn't have to repaint after this was installed!

Anyway, good luck and let me know if you need more detail

Radshire

I have a question too....

I have air bricks, but not at the flooring level - they are about 2 m up in all of the bedrooms upstairs.

Can anyone tell me why I need to keep them...? Spannerzone mentions that they are there to prevent dry rot / rot in the floor boards / joists, but I can't see how mine are any different than having a window open all of the time.

I ask because my 1 year old sleeps in a bedroom which gets incredibly cold. It's drafty too - and this is because of the air brick. I was planning to block it up / have it removed, but I just want to make sure I'm doing the right thing.

Any advice greatly received.

grizzly1911

Air vents are there to provide ventilation;-

As well as preventing damp/ dry rot etc they can also provide an air source for proper fires and gas fires.

A real fire won't burn without oxygen and also as the fumes are sucked up the chimney/flue air has to be replaced from somewhere. The "draw" sucking effect of a real fire can be quite strong.

In older properties you can often find them (whatever purpose) covered/plastered over to prevent drafts.....

Living_proof

When my house was bought about 10 years ago it had no damp proof course and the surveyor insisted on one when it was purchased. It is 200 years old and stone with wooden flooring. Air bricks were placed front and back but not in corresponding places on the front and back wall. Ever since then the floor boards have cupped and the carpet has a corrugated effect. The kitchen floor seems to be sinking. Someone came out to look at it but said it was differences in the relative humidity but I am worried that something wasn't done properly when the damp proof course was done. Does anyone have any specialist knowledge about this problem please?

Radshire

Thanks Grizzly1911
Appreciate that the air bricks are there for ventilation.
However, there are no gas fires in the upper parts of the house.
The combi boiler has it's own ventilation.

Because the room is so cold, I was thinking about covering up the air brick. I know that you can get covers for them, but I wanted to check that blocking it up properly / having it removed was the better solution.
I'm really keen to remove the draft from the bedroom....

grizzly1911

Radshire wrote: »

Thanks Grizzly1911
Appreciate that the air bricks are there for ventilation.
However, there are no gas fires in the upper parts of the house.
The combi boiler has it's own ventilation.

Because the room is so cold, I was thinking about covering up the air brick. I know that you can get covers for them, but I wanted to check that blocking it up properly / having it removed was the better solution.
I'm really keen to remove the draft from the bedroom....

You can get plastic covers that have a sliding mechanism in them that allow you regulate air flow. It would allow you to open them up in the summer and close them up in the winter.

When we had our cavity wall insulation put in (modernish house with fireplace option which we don't use and two concealed vents) the contractor suggested using clear silicone sealant outside to fill the holes in the brick. This was on the basis it could be pulled out again if needed. In the end I just removed the inside plastic covers and taped over the holes and replaced the cover.