Foggy

Thank you for the input everyone. I think I will try to get dmvhr units installed starting with the bathroom. The information here has been really useful and made me feel a lot more confident dealing with companies when I start getting quotes.

Thank you, that was an interesting read.

This is going to get expensive! It would be good to look under the floors though…..

I actually went ahead and got a thermal camera on Amazon. I figure I can sell it after I’m done and recoup some of the cost. I’ve often wondered if there’s any gaps in the cavity insulation so I can give the house a good look over now and see what needs doing. dmvhr is appealing, especially as I can spread the cost by doing one at a time.

Certainly, we do try to open windows a crack when we can but it’s not enough. I didn’t want to waste money getting a bathroom vent installed if a central unit was going to be a better long term solution. It seems like a bathroom extractor is the first thing to do though along with other insulation problem solving.

So that basically means heat recovery is a waste of money in the U.K. unless the house has very low air permeability?

It’s not on exterior walls apart from in one bedroom along the very top corner where it meets the ceiling and the exterior bathroom wall. The latter is almost certainly because we don’t have a shower vent, the walls get wet in there when someone showers, even with the window open. Other than those areas it’s mainly around and on windows, a couple of internal walls and some areas of ceiling. We have some curved corners on a couple of ceilings which are particularly bad, I know those can get missed with loft insulation so that’s another job I know we need to get done at some point. I forget to mention the relative humidity varies between 60% and 75% in the house. The cavity wall insulation was installed about 14 years ago and it’s only the last 2-3 years we have had a problem so I’m hoping that means it’s not causing the problem. The house was fine until we stopped using the open fire. My hypothesis is that open fires suck in a huge amount of air, heat it and then send it out of the chimney before writing us a bill for the fuel so it was acting as a negative pressure ventilation unit. That’s only my ponderings though. The chimney is capped properly with a small vent at the bottom and the top. we don’t have any trickle vents, as far as I know the airbrick is not blocked but getting someone to check the ventilation under the floor is on my list. Thank you for that, that’s really helpful. we are currently waiting to get most of our double glazing replaced because we have some issues with the current units. My worry was that the new UPVC will just make the mould issue worse due to the house becoming less leaky. I’ve been wondering about buying a thermal camera to check for missing spots of insulation as they aren’t too expensive, perhaps that should be something I do this winter.

Hi, since we stopped using and closed off our open fireplace we have had issues with mould forming on walls, ceilings and around windows (mainly upstairs). I know we need to increase ventilation but I’m completely lost about the best way to do this. Our house is a two story 1920s three bedroom semi that’s around 225 cubic meters . We have cavity wall insulation, loft insulation and double glazing along with non insulated suspended floors. Our heating is now gas central heating with rads and smart TRVs. We do not have a bathroom vent at all but we do have an extractor for the kitchen. So I know some kind of vent is desperately needed in the bathroom. I don’t know if it’s worth us getting a heat recovery system given the age of the house but I also want something as eco friendly (and cheap to run) as possible. Especially with uncertainty energy costs in our futures. Given how many different options there are I’d love some advice so that I don’t get taken advantage of when I start getting quotes. So far I’ve looked into options including a standard bathroom extractor and a piv unit, dmev units, heat recovery dmev, a central heat recovery unit for the whole house or if just having vents for the upstairs would work as our loft is relatively open. Money is very much an issue but I don’t want to go cheap on the installation and then be pumping hundreds in heat out of the house each year. I’ve gotten myself completely lost basically.

Hi, I’m slowly trying to turn our house into something as eco friendly as possible on a timescale that would make continental drift look fast. Hoping to get some advice here so that I can maximise when we can do for our budget. Thanks