Attic Insulation-3bed semi

[elchanco]

Hi,

I want to re-insulate my attic this winter. I currently have Rockwool Blown Loft Insulation for the last 5years.
I’m considering insulating over this with new insulation, preferably the type that I can roll between the joists. Is this advisable or should I go to the hassle of removing the old insulation beforehand (id rather just insulate over it).

Also, any recommendations on which type of insulation to use?

I have some condensation on the north facing felt during severe cold snaps. I’m hoping that proper insulation will prevent this occurring.

Any suggestions much welcomed.

 

[mointainwalker]

you don't say how much existing insulation or depth of joists which would have been helpful.

Insulation doesn't wear out so there is no technical reason to remove what you have, it simply creates dirt and mess and expense to do so.

i would simply insulate over it using fibre wool.

You don't mention if you have a vapour barrier between the habitable area and the loft but you should have, if you stop warm moist air getting into the loft ., this should solve your condensation problem.

 

[elchanco]

The depth of the insulation is random. Its blown loose insulation. I have no vapour barrier, have you any examples of this!
cheers

 

[mointainwalker]

The easiest cheapest vapour barrier is plastic sheeting which you should tape at the overlaps to keep the moist air down below.

This really should be laid directly on the ceiling and draped over the joists and then all insulation laid on top.

There is the normal warning about not burying electrical cables under insulation, but this really is only relevant to major current consumers like electric showers or immersion heaters.