The Content Of The Article:

For a house built in 1985 with low insulation on the roof (about 80 mm of glass wool), can we add an insulation of about 100 mm to preserve the view of the beams? Is it possible to add insulation without removing plasterboard and old glass wool? Can we add a vapor barrier before laying the new plates?

This realization of an insulating "mille-feuilles" is particularly complex and very random. There are times when you have to know how to start from a healthy basis, that is to say dismount and redo everything. The overlapping of elements of variable insulating qualities, the absence of vapor barriers suggest that there is a risk of creating the conditions conducive to condensation phenomena, for an inconclusive result. To keep the aesthetic look of the beams inside, why not consider a insulation from the outside of the cover ?

On the same topic

  • Questions answers
    • Can rigid insulation be installed under thin insulation?
    • How to strengthen an existing insulation?
    • How to isolate an apartment from the 1950's?
    • How to soundproof a roof?
  • DIY tips
    • External Thermal Insulation: Insulating and Coating
    • Exterior Thermal Insulation: substrate preparation
    • Lay a double layer of insulation under the roof
    • Exterior insulation made of glass wool and PVC cladding

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