The home comfort collection

Ceiling insulation.A better feeling, room by room.

Comfort starts above the ceiling. Explore Aerolite, Knauf and Isotherm insulation for new homes, renovations and upgrades to existing roof spaces.

Compare the product. Plan the quantity.
Get practical help before you order.

Aerolite glasswool being rolled out between timber ceiling joists Insulation above the ceiling
Comfort you can build on.Warmth in winter. Less heat in summer.
01
36+ years of experience

Practical advice for your insulation project.

02
Three established brands

Compare material, thickness and coverage.

03
Supply & installation options

Order materials or ask for installation help.

01 / Explore the range

Your ceiling. Your choice.

Start with a brand, then choose a thickness on its product page to see current prices and ordering options.

GlasswoolAerolite Soft Touch insulation roll and yellow packaging
ISOVER SOFT TOUCH

Aerolite insulation

Glasswool ceiling insulation with three thickness options for a new installation or a suitable existing-insulation upgrade.

  • 50mm
  • 100mm
  • 135mm
View Aerolite sizes & prices 12, 7.2 or 6m² per roll, by thickness
Glass mineral woolKnauf glass mineral wool roll with blue packaging
WITH ECOSE® TECHNOLOGY

Knauf insulation

Naturally brown glass mineral wool with a plant-based binder. Compare four thicknesses and their different roll coverage.

  • 50mm
  • 75mm
  • 100mm
  • 135mm
View Knauf sizes & prices 9–22.8m² per standard 1.2m-wide roll
PolyesterPackaged Isotherm polyester ceiling insulation
POLYESTER ALTERNATIVE

Isotherm insulation

Polyester fibre insulation for customers who prefer this material. Choose the thickness and confirm the pack specification for your project.

  • 50mm
  • 75mm
  • 100mm
  • 135mm
  • 145mm
View Isotherm sizes & prices Confirm coverage for the selected pack
Insulating a factory, warehouse or large commercial roof?

Explore Factorylite and the industrial insulation range for a specification suited to your roof.

Shop industrial insulation ↗

02 / Compare before you buy

A roll is more than its price.

Thickness affects both coverage and thermal performance. Compare the same application and the R-value you need.

Aerolite Soft Touch

1.2m-wide rolls
Coverage and product thermal resistance
ThicknessCoverage / rollR-value*
50mm12.00m²1.14
100mm7.20m²2.50
135mm6.00m²3.38

Roll lengths: 10m, 6m and 5m respectively.

Knauf Ceiling Roll

1.2m-wide rolls
Coverage and South African product R-values
ThicknessCoverage / rollR-value*
50mm22.80m²1.25
75mm15.36m²1.88
100mm12.12m²2.50
135mm9.00m²3.38

Standard Ceiling Roll / Loft Roll. Other pack formats differ.

Considering Isotherm?

Ask us to confirm the thermal rating and coverage of the exact pack supplied. The roll calculator below also works with Isotherm when you enter the coverage from your pack label or quotation.

03 / Plan your quantities

How many rolls
will you need?

Turn your ceiling area into an estimated order quantity. Choose the product and thickness, add an optional cutting allowance, and we’ll round up to whole rolls or packs.

Ceiling area ÷ pack coverageInclude your allowance, then round up.
  1. Measure the ceiling area in square metres. For a rectangular room, multiply length by width.
  2. Add together the rooms or areas you want to insulate.
  3. Choose your insulation and confirm the pack format before ordering.

This estimates material for one layer. Roof access, obstructions, offcuts and the installation layout can affect the final quantity.

Ceiling insulation calculator

A useful starting point for your materials quote.

Set from the selected roll size.
Optional allowance for cutting or offcuts.
Aerolite · 135mm
Product R-value 3.38 · 5m × 1.2m roll

For a second layer, calculate that layer separately using its own thickness and coverage.

04 / Understand the price

Compare what your money covers.

A lower price per roll does not always mean a lower project cost. Start with the thermal performance your ceiling needs, then compare the cost of covering the same area.

Roll price ÷ coverage
= material price per m²

Use the same VAT basis for every comparison. Whole-roll purchasing and offcuts can increase the effective cost per square metre of ceiling.

  1. Choose a comparable specification

    Consider the material, product R-value and required installation. Equal thickness does not always mean equal thermal performance.

  2. Check the selected product price

    Open the product page and select your thickness for current pricing. Confirm the roll or pack coverage against your choice.

  3. Include the rest of the project

    Ask for delivery and installation to be quoted separately so you can see the full project cost.

Installer fitting Knauf mineral wool insulation in a timber roof space
Plan the installation with the product

Materials & practical installation help

Buying the insulation?
We can help with the next step.

Order your materials from Roof Insulations. For professional installation in Cape Town and surrounding areas, request a quotation through Cape Ceilings & Drywalling.

Share your ceiling area, suburb and any existing insulation details. Roof access and the condition of the ceiling space help determine the scope of the work.

Read our ceiling insulation installation guide

05 / A little clarity before you order

Good questions.
Practical answers.

Choosing ceiling insulation should feel straightforward. If your project needs a closer look, speak to us before placing the order.

Call 087 711 0229 ↗
Which ceiling insulation should I choose?

Start with your project’s thermal requirements, the roof construction and the available installation space. Aerolite and Knauf are glasswool options; Isotherm is polyester. Compare the exact product’s R-value and pack coverage, then ask us to help narrow the choice.

Does thicker insulation always cover less area?

Within the Aerolite and standard Knauf ranges shown here, thicker rolls have shorter lengths and lower coverage per roll. Pack formats also differ between brands. Compare square metres per roll, rather than counting rolls alone.

Is 135mm insulation the right choice for every home?

The correct specification depends on the climate, building and complete roof system. Both 135mm Aerolite and the listed 135mm Knauf Ceiling Roll have a product R-value of 3.38. That figure alone does not establish the performance or compliance of an entire roof assembly.

Can I add insulation over an existing layer?

A top-up may be suitable after the existing material and roof space have been assessed. Check for moisture, damage and installation issues first. The installer should allow for ventilation and the required clearances around electrical fittings and heat sources, following the relevant product and fitting instructions.

Will ceiling insulation soundproof my home?

Fibrous insulation can improve acoustic comfort as part of a suitable ceiling system. Noise control also depends on ceiling boards, gaps, walls and the path the sound takes. For a noise-focused project, explore our acoustic insulation range and ask about the complete construction.

Can I order materials without installation?

Yes. Select your product and thickness to view the supply price and ordering options. Ask us to confirm stock and delivery to your suburb. Professional installation in Cape Town and surrounding areas can be quoted separately through Cape Ceilings & Drywalling.

Why does the calculator ask for Isotherm pack coverage?

The quantity must be based on the exact pack you are buying. Enter the square metres stated on its label or confirmed in your quotation. This avoids using a roll size or grade that does not match your order.

Let’s get your project started

A more comfortable home
starts with a good plan.

Send your ceiling area, preferred brand and delivery suburb. We’ll help you confirm quantities, availability and the next step.

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