Preventing condensation

[Jcloughie]

We had an open cistern in a downstairs cloakroom and it would get condensation even when heating was on. It would drop onto the floor and leave small puddles. Very much dependent on atmospheric conditions or if cooking where the kitchen wasn’t far from the cloakroom.

It is a strange thing as to why some properties seem to suffer more than others. Our houses are just 1970‘s rubbish. Not constructed to a great standard. So far from air tight, though I do try hard to improve it there are inherent problems not possible to improve on. We have very little condensation. Possibly that because, despite all my efforts, the house is ‘airy’.

The house behind us really suffer, in fact they keep Karcher window vacs on the upstairs window ledges!

I wonder if modern houses which are constructed to a minimum air tight standard, suffer more from condensation.

I have two grandsons in such houses, I will have to remember to ask them. May get to see them next year sometime.

Toilet cisterns are an obvious magnet for condensation. But in Beechpee‘s case, ventilating may disperse the collection.



John

 

[Beehpee]

We have double glazing with top vent in every room, we. Have windows open constantly and door to garden off the kitchen open loads for the dog, any more ventilation and I’d have to remove the windows, it could be that bathroom rad is quite close but can’t change the position, as I said it’s not a major problem and I’m sure with better insulation it will stop it altogether.

BP

 

[otherclive]

It is a strange thing as to why some properties seem to suffer more than others. Our houses are just 1970‘s rubbish. Not constructed to a great standard. So far from air tight, though I do try hard to improve it there are inherent problems not possible to improve on. We have very little condensation. Possibly that because, despite all my efforts, the house is ‘airy’.

The house behind us really suffer, in fact they keep Karcher window vacs on the upstairs window ledges!

I wonder if modern houses which are constructed to a minimum air tight standard, suffer more from condensation.

I have two grandsons in such houses, I will have to remember to ask them. May get to see them next year sometime.

Toilet cisterns are an obvious magnet for condensation. But in Beechpee‘s case, ventilating may disperse the collection.



John

Until recently our son lived in a new house circa 2012. It was amazingly warm even with minimal heating on. They had exposed cisterns and never had condensation. Our house is 1986 and our cisterns are all built in concealed insulated tanks; Thomas Dudley Vantage. Might be worth swopping your old one for a newer design.

 

[Beehpee]

My cistern is circa 2019

 

[Beehpee]

I know because I fitted it myself along with a 2019 toilet, shower, radiator, etc etc

BP

 

[otherclive]

Save water bills and water. Don’t use it so often. If it’s yellow let it mellow. If it’s brown flush it down 😱

 

[Beehpee]

Wow OC It’s been a while since that phrase was used, what year was it we had the drought? 76 is the hottest, driest I can remember but don’t think it was that long ago, I suppose if I was to have the pipe work from the hot water filling the cistern that would stop the condensation completely.

 

[Jcloughie]

Until recently our son lived in a new house circa 2012. It was amazingly warm even with minimal heating on. They had exposed cisterns and never had condensation. Our house is 1986 and our cisterns are all built in concealed insulated tanks; Thomas Dudley Vantage. Might be worth swopping your old one for a newer design.

Bit confused OC. Yes my cisterns are exposed, but it’s BP that has the problem. Not I.

John

 

[Beachball]

We have double glazing with top vent in every room, we. Have windows open constantly and door to garden off the kitchen open loads for the dog, any more ventilation and I’d have to remove the windows, it could be that bathroom rad is quite close but can’t change the position, as I said it’s not a major problem and I’m sure with better insulation it will stop it altogether.

BP

In 2008 we brought a brand new 4 bedroom detached our double glazing was the same with a top vent in every room we didn"t have the windows open to much because i suffer with been cold but in our home the bathroom rad was not close to the window or the toilet cistern it probably why we didn"t get any condensation i hope you get it sorted Beehpee .

 

[otherclive]

Bit confused OC. Yes my cisterns are exposed, but it’s BP that has the problem. Not I.

John

To err is human....... must have been your post about the poor standards in house construction 🤭

 

[Buckman]

It is a strange thing as to why some properties seem to suffer more than others. Our houses are just 1970‘s rubbish. Not constructed to a great standard. So far from air tight, though I do try hard to improve it there are inherent problems not possible to improve on. We have very little condensation. Possibly that because, despite all my efforts, the house is ‘airy’.

The house behind us really suffer, in fact they keep Karcher window vacs on the upstairs window ledges!

I wonder if modern houses which are constructed to a minimum air tight standard, suffer more from condensation.

I have two grandsons in such houses, I will have to remember to ask them. May get to see them next year sometime.

Toilet cisterns are an obvious magnet for condensation. But in Beechpee‘s case, ventilating may disperse the collection.



John

In our home we have an extractor running 24/7 365 days a year and this helps to remove moisture content from the home. TBH I thought it was standard in all homes as air bricks have been removed.

 

[otherclive]

In our home we have an extractor running 24/7 365 days a year and this helps to remove moisture content from the home. TBH I thought it was standard in all homes as air bricks have been removed.

We have had homes where we use a dehumidifier which removes moisture and puts some heat back into the house. We still have one which we use instead of a tumble dryer where we cannot air dry outside and the garment cables say no to tumble dryers. It gets placed in an upstairs bathroom and counters away nicely. The condensate I use for mixing with screen wash so no Wiltshire hard water sediment or softener salt residue non the screens.

 

[Beachball]

We have been thinking of putting a new system in it called Loft PIV mounted unit it a ventilation system and condensation control unit for homes with loft space and next door done it and it has worked . our condenser tumble dryer is in the garage and we use it alot in the winter months

 

[Buckman]

We have been thinking of putting a new system in it called Loft PIV mounted unit it a ventilation system and condensation control unit for homes with loft space and next door done it and it has worked . our condenser tumble dryer is in the garage and we use it alot in the winter months

Ours is in the passage way so services all the rooms off the passage. There is the two of us, 3 dogs and 2 cats all exhaling water vapour so it adds up over the night. During the day there is the washing up plus other things that would generate moisture into the air. We are lucky that we have loft space.
Strangely for the first two years that we had it, it never worked although it was switched on. Eventually a repair person opened up the switch to discover that it had been put in upside down. Put it the correct way up and no more issues with condensation.
Also we have a wet room that has an extractor that removes a lot of moisture in the mornings and evenings when showering etc.

 

[Beachball]

Ours is in the passage way so services all the rooms off the passage. There is the two of us, 3 dogs and 2 cats all exhaling water vapour so it adds up over the night. During the day there is the washing up plus other things that would generate moisture into the air. We are lucky that we have loft space.
Strangely for the first two years that we had it, it never worked although it was switched on. Eventually a repair person opened up the switch to discover that it had been put in upside down. Put it the correct way up and no more issues with condensation.
Also we have a wet room that has an extractor that removes a lot of moisture in the mornings and evenings when showering etc.

Hi We also have a wet room but i put the dehumidifier on ...... How much did it cost to put this system in ?

 

[Buckman]

Hi We also have a wet room but i put the dehumidifier on ...... How much did it cost to put this system in ?

It was not expensive at all as it vents into the loft. Basically just a fan with a nice surround.

 

[Beachball]

Well we had someone give us a quote it one thousand pounds so i don"t know whether to get a second opinion for the job ..

 

[ProfJohnL]

It was not expensive at all as it vents into the loft. ..

You should not vent a bathroom or other moisture laden room air into a loft space. It should be vented outside.

 

[Jcloughie]

To err is human....... must have been your post about the poor standards in house construction 🤭

My point was, that it is the poor ‘leaky’ house construction which helps which helps with the condensation.

In our home we have an extractor running 24/7 365 days a year and this helps to remove moisture content from the home. TBH I thought it was standard in all homes as air bricks have been removed.

Absolutely not, air bricks were fitted either to vent a cavity, or a room or under a suspended floor. For the first two reasons they have not been used by anyone with a modicum of building knowledge for about 50 plus years!

Pushing air out with a fan is wasteful and expensive in heating. But it will help with condensation. Modern thinking is air tight with better insulation.

We have been thinking of putting a new system in it called Loft PIV mounted unit it a ventilation system and condensation control unit for homes with loft space and next door done it and it has worked . our condenser tumble dryer is in the garage and we use it alot in the winter months

I have heard of this. Sounds promising, but I have no info.

Ours is in the passage way so services all the rooms off the passage. There is the two of us, 3 dogs and 2 cats all exhaling water vapour so it adds up over the night. During the day there is the washing up plus other things that would generate moisture into the air. We are lucky that we have loft space.
Strangely for the first two years that we had it, it never worked although it was switched on. Eventually a repair person opened up the switch to discover that it had been put in upside down. Put it the correct way up and no more issues with condensation.
Also we have a wet room that has an extractor that removes a lot of moisture in the mornings and evenings when showering etc.

But is yours just a fan as you mentioned earlier? The PIV is much more involved. Mounting a fan just to extract into the loft space will only move the condensation and could lead to structural failure of the roof! PIV work the oposite to an extractor, pushing fresh filtered air in.



Building regs state that bathrooms and toilets must have some form of ventilation. This means a window which can be opened, or mechanical ventilation. An extractor fan.

These fans are normally fitted in rooms without daylight and work off the light switch with an adjustable overrun.

My bathroom does have a window, but there is also an overrun fan above the shower. This is only set to run for 1 minute which is enough to control the ventilation. I have another in the downstairs loo and on the hob extractor. All are fitted with air valves to prevent cold air returning.


John

 

[Beachball]

If that the case John would it be worth putting it in at present we have a moveable dehumidifier, but we have put money aside because our bungalow needs a new roof .

 

[otherclive]

My point was, that it is the poor ‘leaky’ house construction which helps which helps with the condensation.



Absolutely not, air bricks were fitted either to vent a cavity, or a room or under a suspended floor. For the first two reasons they have not been used by anyone with a modicome of building knowledge for about 50 plus years!

Pushing air out with a fan is wasteful and expensive in heating. But it will help with condensation. Modern thinking is air tight with better insulation.



I have heard of this. Sounds promising, but I have no info.



But is yours just a fan as you mentioned earlier? The PIV is much more involved. Mounting a fan just to extract into the loft space will only move the condensation and could lead to structural failure of the roof!



Building regs state that bathrooms and toilets must have some form of ventilation. This means a window which can be opened, or mechanical ventilation. An extractor fan.

These fans are normally fitted in rooms without daylight and work off the light switch with an adjustable overrun.

My bathroom does have a window, but there is also an overrun fan above the shower. This is only set to run for 1 minute which is enough to control the ventilation. I have another in the downstairs loo and on the hob extractor. All are fitted with air valves to prevent cold air returning.


John

“Absolutely not, air bricks were fitted either to vent a cavity, or a room or under a suspended floor. For the first two reasons they have not been used by anyone with a modicome of building knowledge for about 50 plus years!”

Pity the message wasn’t passed to all of the national house building companies as our last house built in 1976 had air bricks and it was on a concrete slab. The only condensation was in a downstairs cloaks where the water came in virtually straight off of the stop ****, so was cold on entry.

 

[Jcloughie]

“Absolutely not, air bricks were fitted either to vent a cavity, or a room or under a suspended floor. For the first two reasons they have not been used by anyone with a modicum of building knowledge for about 50 plus years!”

Pity the message wasn’t passed to all of the national house building companies as our last house built in 1976 had air bricks and it was on a concrete slab. The only condensation was in a downstairs cloaks where the water came in virtually straight off of the stop ****, so was cold on entry.

Just remembered, there was a 4th reason for air bricks for use in a larder. (remember them). Fridges made that idea obsolete. and the 5th to provide air to a gas appliance.

As an apprentice in 1966, I was aware of that cavity ventilation was very counter intuitive and actually has a refrigeration effect on a property. It does help a little with damp prevention but at the same time encourages internal condensation, remember all the mildew.

Also that through ventilation into rooms usually at a higher level. Just wasted heat. and chilled the area around the vent building up more condensation and mildew.

I built many houses in the 70's and 80's. Never installed any air bricks and I was never asked to.

So yes. Your builder was not up to date. But most builders, designers and architects weren't, and many still aren't. Sad to say.

The BR came into force in 1966 but many were unaware and they were in their infancy. Big revision in 1972. and another in 1976 with incorporation into the HSAWA. 1974 That's when it really started to take affect. With many improvements since then.

John

 

[Jcloughie]

If that the case John would it be worth putting it in at present we have a moveable dehumidifier, but we have put money aside because our bungalow needs a new roof .

I don't have any experience of PIV in domestic properties so don't feel I can advise. But it certainly something to look into. I did look many years back and it was very expensive. Seems you can buy units for about £350 now. (plus fitting).

John

 

[otherclive]

Here is a Building Research Establishment report summary of the effects of PIV in a “laboratory test house” and a number of occupied private dwellings. It’s a balanced non commercial paper. Far more balanced than some of the claims made by vendors of PIV systems. For example one claims the loft space can be 30 deg C higher than the ambient in the house. And by ducting air via the PIV you effectively get free heat. But who would want that on a hot summers day, that’s when we close up, draw blinds and rely on our insulation to keep cool, just like in hot countries, where at those temperatures condensation is not a problem.

https://projects.bre.co.uk/positivevent/

 

[Jcloughie]

Here is a Building Research Establishment report summary of the effects of PIV in a “laboratory test house” and a number of occupied private dwellings. It’s a balanced non commercial paper. Far more balanced than some of the claims made by vendors of PIV systems. For example one claims the loft space can be 30 deg C higher than the ambient in the house. And by ducting air via the PIV you effectively get free heat. But who would want that on a hot summers day, that’s when we close up, draw blinds and rely on our insulation to keep cool, just like in hot countries, where at those temperatures condensation is not a problem.

https://projects.bre.co.uk/positivevent/

Well done for finding that. Very interesting. Sounds good in Beachpees case but it says of little use if there is no condensation problems.

Interesting that it showed on test, a higher loft humidity due to leakage from the house. No doubt older properties without a vapour barrier, like mine. I would have thought that if there is decent loft insulation the humidity would match that of the outside.

Some also claim that it can keep Radon at bay.

John