ROOF INSULATIONS · PRODUCT COMPARISON
Aerolite vs Knauf insulation.
Find your best fit.
Same published R-value. Different roll sizes. Compare two popular ceiling insulation options and see what each will cost for your space.
A like-for-like look at 135mm Aerolite® Soft Touch and 135mm Knauf Ceiling Roll.
AEROLITE® SOFT TOUCH
135mm Aerolite
R3.38Published product R-value6 m² per 1.2m-wide roll
KNAUF CEILING ROLL
135mm Knauf
R3.38Published SA product R-value9 m² per 1.2m-wide roll
Packaging is illustrative and may show an older specification. Confirm the declaration on the supplied rolls. Specification sources.
THE PRACTICAL VERDICT
Start with the specification.
Choose on the complete quote.
A useful Aerolite vs Knauf insulation comparison begins with matching thicknesses. At 135mm, both publish R3.38 and both are classified as non-combustible. The choice comes down to the supplied format, handling preferences and your final project cost.
Our recommendation: request a quote for both. Aerolite’s smaller roll may suit your quantities; Knauf’s larger roll covers more area per pack. If ECOSE® binder is a priority, look at Knauf.
Compare price per square metre, then check whole-roll totals. This Aerolite vs Knauf insulation guide helps you make that decision using your own measurements and quotations.
THE DETAILS, SIDE BY SIDE
Aerolite vs Knauf insulation comparison
These figures apply to the selected 135mm ceiling rolls. Other thicknesses have different performance and coverage.
| What you are comparing | 135mm AeroliteSoft Touch ceiling insulation | 135mm KnaufCeiling Roll / Loft Roll |
|---|---|---|
| Material & binder | Glasswool with thermosetting resin binder | Glass mineral wool with bio-based ECOSE® binder |
| Nominal thickness | 135mm | 135mm |
| Published product R-value | 3.38 m²·K/W | 3.38 m²·K/W South African declared value |
| Roll dimensions used here | 5m × 1.2m | 7.5m × 1.2m |
| Coverage per roll | 6 m² | 9 m² |
| SANS 428 register entry | A/A1/1 Non-combustible | A/A1/1 Non-combustible |
| SANS 53501-1 register entry | A1 | A1 |
| Published NRC | 1.10 Sound absorption figure | 1.13 Sound absorption figure |
| Compare price per m² | Quoted roll price ÷ 6 | Quoted roll price ÷ 9 |
| Check before ordering | Thickness, pack coverage and required quantity | Thickness, uncut or combi-cut format, and pack coverage |
Swipe the table sideways to see both products.
Showing all 10 comparison points.
WHAT MAKES THE DIFFERENCE?
Good insulation starts with a good fit
Put Aerolite vs Knauf insulation specifications into context. The right product needs the right installation, with a quotation that covers the actual job.
Matching R-values. Careful installation.
The published figures in this Aerolite vs Knauf insulation comparison do not establish a thermal winner at 135mm. Ask your installer how the insulation will fit around the ceiling framing and service routes.
Plan for continuous coverage without gaps or unnecessary compression. A total roof R-value needs an assessment of the roof-and-ceiling construction; it is not a fixed uplift added to every roll.
Both have non-combustible classifications
For these products, Aerolite vs Knauf insulation is a comparison of two non-combustible options. Their entries in the cited fire register match. A blanket’s reaction-to-fire class does not give the entire ceiling a fire-resistance period.
Follow the specified clearances and protection requirements around lights, flues and other heat sources. Check those details with the installer before work begins.
Consider the roll format and feel
Handling is a practical part of Aerolite vs Knauf insulation. Aerolite Soft Touch uses a thermosetting resin binder; Knauf’s ECOSE® binder is bio-based, with no added formaldehyde or phenol.
Knauf offers uncut and combi-cut formats. Confirm which you are buying and whether it suits the framing. Follow each manufacturer’s cutting and handling guidance, whichever product you select.
Look beyond a single number
An Aerolite vs Knauf insulation acoustic comparison needs comparable test conditions. The small difference in published NRC figures does not establish how much quieter your finished room will be. The whole construction matters.
For lasting performance, keep the insulation dry, supported as specified and undamaged. Ask for evidence before accepting claims that one brand always lasts longer.
FROM CEILING AREA TO SHOPPING LIST
Aerolite vs Knauf insulation cost calculator
Enter your ceiling area to estimate rolls. Add current quoted prices to compare material cost per square metre and the total for the whole rolls you need.
Prices are optional. Use VAT-inclusive prices for the 135mm rolls compared here. The allowance is adjustable; confirm a suitable amount for your ceiling layout.
135mm Aerolite
135mm Knauf
100 m² + 5% allowance = 105 m² to cover. Add both roll prices to compare material totals.
Estimate only. Excludes installation, delivery and accessories. Uses 6 m² Aerolite and 9 m² Knauf rolls, rounded up to whole rolls. Confirm measurements and pack coverage before ordering.
Complete your Aerolite vs Knauf insulation price comparison with delivery and installation charges. Ask for the same scope of work on both quotations.
The material price per square metre divides the quoted price by the area in one roll. The project total uses the complete rolls you would buy, including any unused material. This is why two products with an identical price per square metre can produce different totals for a small ceiling. Use the purchased coverage figure to see the difference.
BEFORE YOU BUY
Three checks for a better purchase
Measure the ceiling
Use the ceiling area being insulated, rather than the sloping roof area. Check separate rooms, extensions and awkward sections, then agree a cutting allowance with your installer.
Match the quotations
Finish your Aerolite vs Knauf insulation comparison with the thickness, coverage, quantities and VAT basis written down. Check stock and delivery before arranging installation.
Check the roof space
Confirm safe access, existing insulation and any leaks or electrical work needing attention. Have the required thermal performance and installation details checked for your building.
STRAIGHT ANSWERS
Aerolite vs Knauf insulation FAQs
Make a confident choice with clear specifications and a complete quote. These answers cover the questions that matter before ordering.
Is Knauf better than Aerolite?
For Aerolite vs Knauf insulation at the selected 135mm thickness, both publish R3.38 and have non-combustible classifications. Compare roll format, handling preferences and the delivered project price. Those details are more useful than a universal brand ranking.
Why does a Knauf roll cover more area?
The specified 135mm Knauf roll is 7.5m long, while the Aerolite roll is 5m long. Both are 1.2m wide. That gives 9 m² and 6 m² respectively. Other thicknesses use different roll lengths, so always read the pack label.
Which one is cheaper for my ceiling?
Aerolite vs Knauf insulation prices should be compared per square metre and by whole-roll purchase total. Use the calculator with current quotations, then add delivery and installation. A lower sticker price per roll does not necessarily mean a cheaper completed job.
Is R3.38 the same as a total roof R-value?
No. Product R-value describes the insulation itself. Total R-value relates to the roof-and-ceiling assembly. Keep those figures separate when comparing quotes, and have the required overall performance checked for your building.
Does the higher NRC mean a quieter home?
The published NRC figures alone cannot establish that outcome. In an Aerolite vs Knauf insulation sound comparison, ask about test conditions and the complete ceiling design. Sound absorption and sound transmission through a roof are different measures.
Can I install either product myself?
Only where access is safe and you can follow the manufacturer’s instructions. Avoid stepping on ceiling boards and follow the requirements around heat-producing fittings. Arrange professional help for difficult access or electrical work.
READY TO COMPARE YOUR QUOTE?
Two good options.
One properly planned project.
Need help with Aerolite vs Knauf insulation? Send us your ceiling area and suburb or town. We can help you check the available products and prepare your enquiry.
Specification sources & comparison notes
- Isover Aerolite® Soft Touch technical datasheet (PDF) and manufacturer product page.
- Knauf Ceiling Roll / Loft Roll datasheet, September 2025 (PDF). Uses the published South African R-value.
- TIPSASA fire classification register, June 2024, Table 1 (PDF).
- Knauf Insulation: ECOSE® binder technology.
Sources reviewed October 2026. Confirm current documentation for the stock quoted. Published figures are not a guarantee of identical installed performance, energy savings or sound reduction in every home.
