DAMP/VENTILATION/AIR BRICKS NEEDED?

[Richm1085]

Hi everyone

We own a 1930s semi detached.

In winter we experience damp in the bottom left corner beside the front door area.

There were 2 air bricks, one on the front wall, and one on the side wall, right on this corner. However these were cemented over because we the house had the polystyrene ball cavity wall insulation and the builder said the air bricks would just allow the insulation to move the rain etc from outside to inside.

This made no difference, so we had the cavity wall insulation removed under the warranty. It would appear our house would never have been suitable for it anyway, but the previous owner was obviously talked into getting it by one of those scam companies 10 years or so a go.

The CWI has been removed for about 3 years now but the damp continues in that corner.

We have no air bricks anyway around the exterior of the house.

I was going to put a vent in this bottom corner going from inside to outside to get a bit of air flow, but should we get some air bricks back now the CWI has gone?

Would have done it sooner but had a new roof and kitchen etc, now thats all done I want to address this issue.

These old houses have no real ventilation

Any advice greatly appreciated

 

[foxhole]

Old properties usually have lots of ventilation due to being built in the coal fire era .

 

[Richm1085]

Old properties usually have lots of ventilation due to being built in the coal fire era .

Ok, well ours has no chimney, everything been sealed up etc by previous owner to keep heat in

 

[spannerzone]

A sealed up house might well suffer from moisture, those sealed up airbricks might be the first thing I'd sort out just to get the house breathing again. Do you have extractor fan in kitchen and the bathroom and use them? do you dry clothes indoors? all that creates moisture that might condensate on a cold internal wall. Do you see if having a window slightly open to let out your moisture (breathing!) makes any differnce? Damp can come from many sources, so do a little research and don't just get a 'damp specialist' in, as they will, almost guaranteed, suggest a damp proof course treatment of injections and replastering, often all unnecessary.

My 100 year old home has very mild damp on the ground floor walls and it's condensation forming, so I installed a PIV fan (positive input fan) in the loft which gently blows air from the loft into the house and this can greatly help woth some damp issues.

Of course you could have other issues like water getting in from outside due to leaking gutters, down pipes, ground level outside to high and bridging the damp proof course, the cavity might be blocked or bridged, allowing a wet exterior wall water in across to internal wall, that rendering might be allowing water in, many things can cause damp so some time and effort is needed.

 

[Richm1085]

A sealed up house might well suffer from moisture, those sealed up airbricks might be the first thing I'd sort out just to get the house breathing again. Do you have extractor fan in kitchen and the bathroom and use them? do you dry clothes indoors? all that creates moisture that might condensate on a cold internal wall. Do you see if having a window slightly open to let out your moisture (breathing!) makes any differnce? Damp can come from many sources, so do a little research and don't just get a 'damp specialist' in, as they will, almost guaranteed, suggest a damp proof course treatment of injections and replastering, often all unnecessary.

My 100 year old home has very mild damp on the ground floor walls and it's condensation forming, so I installed a PIV fan (positive input fan) in the loft which gently blows air from the loft into the house and this can greatly help woth some damp issues.

Of course you could have other issues like water getting in from outside due to leaking gutters, down pipes, ground level outside to high and bridging the damp proof course, the cavity might be blocked or bridged, allowing a wet exterior wall water in across to internal wall, that rendering might be allowing water in, many things can cause damp so some time and effort is needed.

Thanks for this reply.

We have a good kitchen extractor fan which is always in use when cooking. Likewise in the bathroom.
We don’t dry clothes on radiators, only in the tumble.

I’ve been leaving the hall, spare bedroom and bathroom windows open on the latch overnight - with our bedroom door open a bit and we’re getting no condensation in the bedroom windows now.

Roof/gutters all good - brand new last year.

I will re hole the air bricks but I’ve been looking at a PIV unit a lot recently and think it’s worth a shot.

Just researching now whether a heated one is more beneficial and how much more they cost to run because of the heater.

 

[spannerzone]

Thanks for this reply.

We have a good kitchen extractor fan which is always in use when cooking. Likewise in the bathroom.
We don’t dry clothes on radiators, only in the tumble.

I’ve been leaving the hall, spare bedroom and bathroom windows open on the latch overnight - with our bedroom door open a bit and we’re getting no condensation in the bedroom windows now.

Roof/gutters all good - brand new last year.

I will re hole the air bricks but I’ve been looking at a PIV unit a lot recently and think it’s worth a shot.

Just researching now whether a heated one is more beneficial and how much more they cost to run because of the heater.

I got the heated PIV nuaire version, installed it probably 7 years ago and have never once used the heater element as not really found the need...sure you do get a slightly cool downward draught when standing underneath the fan vent in the hall at top of stairs, but by the time the air has gone downstairs and circulates, it really isn't that noticable. I run the PIV on the lowest fan speed (barely audible, gentle downward airflow) so perhaps a larger house using faster speed might generate more cool air so heater might help... but running a 500watt (I think) heating element for hours on end won't be cheap nowadays! - the fan, without heater, probably consumes 20watts I reckon, so pretty negliable running costs.

Another big benefit is when I go on holiday and lock all windows, this PIV means the house doesn't have a stale smell when I return, the house smells fresher. In the hot summer months, the fan stop working when temps get too warm in the loft, to prevent venting hot humid air into the home.

If you've got damp, got a suitable place to fit the fan (mine is suspended by strong string in a beam to prevent vibration noises) and suitable ceiling space (above stairs to vent straight down is ideal) then I think it might be worth a shot.

I also had bricked up airbricks - first job I did was fit a couple of new one front' back and side of house, when I had the brick out, I reached in to remove any rubble that could bridge the in and outside walls and allow outside damp to get across. My previous home owner had done lots of poor internal plastering with modern plaster products and nasty foiled wall coverings (I assume to try hide the damp) this only made things worse.

 

[Richm1085]

I got the heated PIV nuaire version, installed it probably 7 years ago and have never once used the heater element as not really found the need...sure you do get a slightly cool downward draught when standing underneath the fan vent in the hall at top of stairs, but by the time the air has gone downstairs and circulates, it really isn't that noticable. I run the PIV on the lowest fan speed (barely audible, gentle downward airflow) so perhaps a larger house using faster speed might generate more cool air so heater might help... but running a 500watt (I think) heating element for hours on end won't be cheap nowadays! - the fan, without heater, probably consumes 20watts I reckon, so pretty negliable running costs.

Another big benefit is when I go on holiday and lock all windows, this PIV means the house doesn't have a stale smell when I return, the house smells fresher. In the hot summer months, the fan stop working when temps get too warm in the loft, to prevent venting hot humid air into the home.

If you've got damp, got a suitable place to fit the fan (mine is suspended by strong string in a beam to prevent vibration noises) and suitable ceiling space (above stairs to vent straight down is ideal) then I think it might be worth a shot.

I also had bricked up airbricks - first job I did was fit a couple of new one front' back and side of house, when I had the brick out, I reached in to remove any rubble that could bridge the in and outside walls and allow outside damp to get across. My previous home owner had done lots of poor internal plastering with modern plaster products and nasty foiled wall coverings (I assume to try hide the damp) this only made things worse.

Thanks. Sounds so similar to my situation. I think we will try the PIV and sort a few air bricks out!

 

[spannerzone]

Yeah probably worth a shot, many have found it helps them.