Loft condensation

[Dapph2]

Dont know how old you are matey, but a 1970,s home is not classed as old ...it was just after this era that the troubles started with the double glazing boom with plastic and aluminium windows. A house needs to breath as its a living entity with all the occupants in it...classic case is the fashion of removing chimney pots and capping the stacks resulting in the mid-feathers (inside brickwork) becoming dripping wet.

Around 1984 on for several years " Geoff Cape's impermeable membrane " two fused plastic grey sheets with a Kevlar netting inside the sheeting " . This roofing membrane was being promoted by him and various builders as being strong enough to toss him up in the air like a birthday boy in a blanket .

The only problem was the whole roof void was basically sealed , so whatever moisture permeated through plaster ceiling boards and the fibre glass insulation simply condensed on the plastic sheeting . In a lot of cases here in wet Wales actually rotting the tile batons and occasionally the actual roof trusses .
I would say that not one of the tile batons was found to be rot free when we had the roof replaced three years ago ..our place was thrown up in Sept 1987 . Now my roof has a one way breathable membrane under the concrete tiles & I put a 6 inch vent hole with a fixed louvre plate in each gable end ..it's lovely dry & cold in the roof void this winter not a hint of condensation .

 

[Dapph2]

I did exactly the same with my knees too

For anyone else reading this post ..use a seven foot length or so of skirting board or similar with W's cut in one end and use it like fork to roll out & place insulation in the awkward to reach places.

 

[Bobtail4x4]

Around 1984 on for several years " Geoff Cape's impermeable membrane " two fused plastic grey sheets with a Kevlar netting inside the sheeting " . This roofing membrane was being promoted by him and various builders as being strong enough to toss him up in the air like a birthday boy in a blanket .

The only problem was the whole roof void was basically sealed , so whatever moisture permeated through plaster ceiling boards and the fibre glass insulation simply condensed on the plastic sheeting . In a lot of cases here in wet Wales actually rotting the tile batons and occasionally the actual roof trusses .
I would say that not one of the tile batons was found to be rot free when we had the roof replaced three years ago ..our place was thrown up in Sept 1987 . Now my roof has a one way breathable membrane under the concrete tiles & I put a 6 inch vent hole with a fixed louvre plate in each gable end ..it's lovely dry & cold in the roof void this winter not a hint of condensation .

they then brought out a "breathable" type, each square had a pinprick,
didnt really work,

 

[Dapph2]

they then brought out a "breathable" type, each square had a pinprick,
didnt really work,

I guess it still condensed but it ran round the hole and dripped onto the insulation?

 

[gaz1]

For anyone else reading this post ..use a seven foot length or so of skirting board or similar with W's cut in one end and use it like fork to roll out & place insulation in the awkward to reach places.

use a hoe rake or extending pole does much better than your skirting board if i was doing what you ask then id use architrive instead

 

[Monkey Harris]

Our 1930s house had no ventilation fitted in the roof space

It was gently vented by air bricks in the cavity,
At damp proof level

This was adequate until..
The cavities were filled,

a year or two later it smelt damp,

Added some spacer vents in each felt over lap and its now fine,

It has a velux, so I leave it cracked open..