Discussion on options to top up the existing material, either with blow-in insulation to fill all the gaps, or by laying batts over the top of the current material...

Why would I top up my old insulation?

If your insulation is more than 15-20 years old, it would have been only 50-80mm thick originally, and is not stopping your heat loss/gain. You will improve the temperature by 4-8 degrees by improving your insulation, as well as saving yourself hundreds of dollars each year.

Best of all, new insulation is guaranteed for the life of the building, meaning you wont have to worry about it ever again!

Do I lay batts on the old material, or pump insulation over the existing batts?

If your existing batts are very neatly laid, without settling or disturbance, it may be possible to effectively lay new batts on top of the old material. If you have degraded batts, or loose insulation on top, it is not effective to put batts on old material (see Removing old Insulation).

The most effective way to top-up old material is to pump insulation onto the old material. This will fill up every missing piece and gap, and bring all the insulation up to a consistent R-Rating through-out the home. CSIRO figures state that every 1% gap drops the efficiency of the insulation by 5%, and if your insulation has 5% gaps, you have lost 30% of the benefit of your insulation!!

What types of insulation can be pumped over the old material?

There are 2 forms of material that can be pumped over the existing material, being Cellulose or Rockwool.

Cellulose is made from recycled paper, treated with a fire retarding and insect resisting, non-hazardous additive, allowing it to easily be pumped into ceilings. 

Rockwool is made from lightweight insulation manufactured from a molten mixture of natural rock and recycled blast furnace waste products. As it is made from natural rock, it is totally fire-proof (one version is even designed purely for fire walls), and no insects are attracted to it. Rockwool can be pumped into all ceilings, as well as beng pumped into new and existing walls (see Insulating Existing Walls). 

What if I want to use batts?

We are happy to use batts if that is your preference, but we will inspect the job first and advise if you will receive any benefits by laying batts on top of old batts. It may be better to remove and replace the old material if you prefer batts.

Benefits of topping up old insulation by pumping new insulation over old insulation

  • All gaps comletely filled, meaning no heat loss/gain
  • Simple job, done within a few hours
  • All work completed from outside in most homes, meaning you dont even need to be home
  • Your energy bills will be reduced by 30-50%, saving you money forever

How do I find out more information or arrange a quote?

Please Contact Us or fill out our simple form below and we will contact you to discuss potential solutions for your home.


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