Redoing old insulation - worthwhile?

Discussion in 'Renovation & Home Improvement' started by Calder&Scale, 14th Jan, 2023.

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  1. Calder&Scale

    Calder&Scale Well-Known Member

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    We own a 1970-1980s build and will be doing some light renovations.

    Is it worthwhile to consider redoing the insulation/ or at least some of it?

    We are adding downlights, which would mean (I assume) that holes would need to be cut in the insulation - so why not replace it beforehand?

    We are also redoing the flooring (vinyl plank), would this allow us to insulate the floor also? From my research it seems floor insulation is usually done from below, however the crawl space under the house is incredibly small, I'm not sure it's possible to have this done.

    For reference we have gas ducted heating which costs a decent amount to run.
     
  2. Propin

    Propin Well-Known Member

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    What type of insulation do you have? Wool is the best. Others are pretty crappy and stop working over time.
     
  3. Calder&Scale

    Calder&Scale Well-Known Member

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    I'm not sure of the material, it's some sort of mat/ baton
     
  4. Joynz

    Joynz Well-Known Member

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    Get the ‘zero clearance’ down lights and/or use hoods to reduce the lost insulation (and heat loss). Don’t replace it unnecessarily it’s a waste of resources. Batts should still be perfectly fine - just add another layer.
     
  5. Joynz

    Joynz Well-Known Member

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    You’re wrong. Fiberglass, rock wool and polyester batts certainly keep working if installed properly.

    And they definitely aren’t ‘pretty crappy’.
     
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  6. Gimm

    Gimm Well-Known Member

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    How do they 'stop working'?
     
  7. Propin

    Propin Well-Known Member

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    Sorry I could be wrong, just going off my own experiences. Maybe I keep buying properties with this insulation from the mid 90’s. I’ve seen my neighbours getting it sucked out and replaced, My cousin owned an insulation company for a while, he recommended the wool type as the best, so just going off that.
     

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  8. Gimm

    Gimm Well-Known Member

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    Ahh that stuff is bloody annoying. Have it in my PPOR and I always seem to bring a bunch back down the manhole with me every time I work up in the roof space :confused:
     
  9. Westminster

    Westminster Tigress at Tiger Developments Business Member

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    Do you have a timber floor or concrete?

    If you were using some sort of hybrid vinyl plank which has more structure to it then you might be able to lay some thin underlay but if it's loose lay vinyl planks then it's just usually nothing. If it's on a wooden floor base which has some gaps which leak in/out air then putting new flooring over it can help seal those gaps.
     
  10. Calder&Scale

    Calder&Scale Well-Known Member

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    I've had another look under the house (on stumps) and it seems like we should be fine to attach it to the subfloor as normal, so that'll probably be the route we take - assuming it's cost effective.
     
  11. Westminster

    Westminster Tigress at Tiger Developments Business Member

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