Insulation does not last forever. Over time it can settle, get wet, be disturbed or simply turn out to be too thin by today’s standards. The question is whether yours needs a top-up, a replacement or removal.
If you are more interested in how your home feels, such as cold rooms and draughts, start with how to tell if your home needs an insulation upgrade. This post is about the insulation itself.
Signs the insulation itself has a problem
It has been squashed or has slumped
Batts work by trapping air. When they are compressed, or have slipped down and left gaps, they do less. You will often see this in ceilings where things have been stored or tradespeople have walked.
Gaps and missing patches
Look around hatches, downlights, pipes and wiring. Gaps at the edges and corners are common, and they let heat straight through.
Stains, dampness or mould
Water marks, dampness or mould on insulation or the timber around it point to a leak, condensation or a lack of ventilation. Wet insulation does not work properly, so the cause needs fixing as well as the insulation.
Rodent damage
Droppings, shredded material or nesting mean pests have made themselves at home. Insulation that has been used as bedding or a toilet is not worth keeping.
Very thin, or old and powdery
Insulation installed a long time ago may be thinner than what is normal now. If it has also turned dusty, brittle or crumbly, it is a candidate for replacement.
Old loose fill
If the ceiling has loose, fluffy fill rather than batts, that is a different job. It generally needs to be removed before new insulation goes in. See our page on Insulfluff removal.
Top up, replace or remove?
Top up when what is there is dry, clean and in reasonable shape but thin. Adding a layer of new ceiling insulation on top is often the simplest fix.
Replace when the existing insulation is damaged, wet, soiled by pests or badly compressed. The old material comes out and fresh batts go in. We use Knauf batts in ceilings and Mammoth under floors.
Remove when it is old loose fill, or when there is a problem such as persistent damp that has to be dealt with first.
Fix the cause. Insulation damaged by damp will be damaged again if the damp stays. A leaking roof, poor ventilation or wet ground under the house has to be addressed too. For the underfloor, a ground moisture barrier is often part of the solution, alongside underfloor insulation.
Do not forget ventilation
Insulation and ventilation work together. A well-ventilated home is less prone to the condensation and mould that damage insulation in the first place. If you are not sure whether ventilation is part of your problem, mention it when we do your assessment.
What the process looks like
- A free consultation and assessment. Most are done through our online system, and we visit in person for complicated homes or on request.
- A clear, detailed quote with no hidden fees.
- Scheduling to suit you.
- A final quality check once the work is done.
Most ceilings take 1 to 3 hours, and an underfloor job for a 100m² home typically takes a day. As a guide for a 100m² home, ceiling insulation is usually $1,600 to $2,000 and underfloor $2,200 to $2,500. Your quote depends on access and materials. If you’re not satisfied, we’re not finished.
If you rent out the property
Tired or damaged insulation is also something landlords need to watch. Our landlord’s checklist explains what to check.
Get your insulation looked at
Not sure what you have, or what it needs? Get a free, no-obligation quote. We are licensed and insured, and we work across the Bay of Plenty, Coromandel and Hauraki, Gisborne and the East Coast, and the Rotorua and Taupō area. We aim to call you back within 48 hours, or you can call 027 482 0333.