Insulating upstairs floor void in chalet bungalow.

[TheTeaBoy]

Hello,

 

I am currently installing insulation in the pink and purple areas to the upstairs of my parent’s chalet bungalow. I’m doing this while avoiding any destruction that would result in re-decorating.

 

 

The pink area is to plug the floor void at both ends for three reasons:

1. Stop drafts that that make the upstairs floor cold during winter

2. Stop drafts coming through the downstairs light fittings

3. Direct the heat from downstairs to the upstairs rooms instead of losing it to the triangular crawl spaces either side of the house.

 

The upstairs rooms have either laminate or vinyl flooring and I am concerned that if I use foil faced PIR in the pink area it may trap moisture in the floor void particularly above the kitchen and bathroom, which is downstairs, neither of which have extractor fans.

 

The purple area will be some type of roll insulation. If I stuffed the end of this into the pink area instead of using PIR would this better allow moisture to escape into the ventilated triangular crawl space while retaining heat in the floor void?

 

Thank you for any help.