Selecting a roofer

[robinbanks]

Had a chat with checkatrade

Oh no

Venting plus a dehumidifier has solved it

Sounds like your life habits might be putting too much moisture in the air in the first place..

he just took some pictures from the outside

maybe lacked the brain cell count required for drone pilotry

 

[Phil473]

Oh no

We regulary vent, run a dehumidifier. These houses are prone to condensation once double glazing has been installed and chimneys sealed.

I get that checkatrade aren't the best, but what else is there? Any reliable roof federations with reliable members?

 

[robinbanks]

These houses are prone to condensation once double glazing has been installed and chimneys sealed.

No house is prone to condensation unless humans live there. Nothing about a building intrinsically generates airborne moisture

If you've installed more airtight windows and blocked the chimney, then you've potentially considerably cut down the amount of background ventilation the property previously enjoyed. If you've then carried on with lengthy hot showers, boiling to cook things, drying washing on radiators, having tumble dryers that don't vent well to outside, lots of plants, or even just having lots of people in the house you've got the same moisture loading going on but a cut in the background venting means your inner humidity is higher. Couple it up with colder weather, lower ambient temps and it's a condensation generator as the external surfaces are cool

The solution to it all is to strive for balance; the moisture that goes into the air needs to stay there til it's outside the building, and some measure of reducing the moisture, or increasing the temperature and/or ventilation is required

 

[Phil473]

My understanding is that 1930's houses were designed with single glazed windows in mind, so the switch to double glazing produced potential condensation issues.

 

[Phil473]

No house is prone to condensation unless humans live there. Nothing about a building intrinsically generates airborne moisture

If you've installed more airtight windows and blocked the chimney, then you've potentially considerably cut down the amount of background ventilation the property previously enjoyed. If you've then carried on with lengthy hot showers, boiling to cook things, drying washing on radiators, having tumble dryers that don't vent well to outside, lots of plants, or even just having lots of people in the house you've got the same moisture loading going on but a cut in the background venting means your inner humidity is higher. Couple it up with colder weather, lower ambient temps and it's a condensation generator as the external surfaces are cool

The solution to it all is to strive for balance; the moisture that goes into the air needs to stay there til it's outside the building, and some measure of reducing the moisture, or increasing the temperature and/or ventilation is required

The new roof will have a breathable underlay. How breathable are these underlays exactly?

 

[robinbanks]

Should be in the manufacturers spec sheet, but suffice to say if you do have a problem with loft condensation already, expect to see it collecting on the underside of the membrane