What Is Isotherm Insulation and Why Does It Matter?
Isotherm is South Africa's leading ceiling and roof insulation product, manufactured from recycled PET plastic bottles. It is non-toxic, non-irritant, fire-retardant, moisture-resistant and SANS 10400-XA compliant — making it the safest and most practical insulation choice for South African homes and businesses.
Most South African homes lose between 25–40% of their heating and cooling energy through an uninsulated ceiling. In Gauteng, where winters are bitterly cold and summers are intensely hot, this represents a significant and recurring cost. A properly installed insulation layer acts as a thermal barrier — slowing heat transfer in both directions and dramatically reducing your reliance on heating and air-conditioning.
RR Roof Waterproofing installs Isotherm insulation in existing homes and new builds across Centurion and Gauteng. Our installers are experienced, efficient and take care to work cleanly — ensuring your ceiling boards and light fittings are undisturbed throughout the installation.
5 Key Benefits of Isotherm
Insulation Installation
Lower Energy Bills
Properly installed ceiling insulation reduces heating and cooling costs by 20–40%. In Gauteng's climate, most homeowners recover the cost of installation within 2–4 years through energy savings alone.
Year-Round Comfort
Insulation slows heat transfer in both directions — keeping your home warmer in winter and cooler in summer without increasing your energy consumption.
Non-Toxic & Safe for Families
Unlike fibreglass insulation, Isotherm is made from recycled plastic bottles. It contains no formaldehyde, no glass fibres and no irritants — completely safe for homes with children, pets and allergy sufferers.
SANS 10400-XA Compliance
South African building regulations require minimum insulation values in new construction. Isotherm installation ensures your property meets or exceeds current energy efficiency standards.
Noise Reduction
Isotherm's density provides meaningful acoustic insulation — reducing impact and airborne noise transmission between floors and from the roof space. A noticeably quieter home is a welcome bonus.
Isotherm Insulation for
Every Property Type
Home Insulation
Your home's comfort starts with a properly insulated ceiling. Isotherm keeps your house cool in summer and warm in winter, reducing energy bills and improving indoor air quality — with no irritation or toxins safe for children and pets.
Most residential installations are completed in a single day with minimal disruption.
Commercial Insulation
Comfort and energy efficiency matter for staff, customers and compliance. We install Isotherm in suspended ceilings, flush installations and exposed roof trusses for a wide range of commercial environments.
We work around your operating hours to keep business disruption to a minimum.
Industrial Insulation
Warehouses, plants and depots require insulation that is durable, compliant and resistant to industrial activity. Isotherm's fire-retardant and fibre-free design makes it ideal for demanding industrial environments.
We install Isotherm Roof Liner directly under roof sheeting where no conventional ceiling exists.
Our Insulation Installation Process
We install insulation efficiently and cleanly, with minimal disruption to your home or business. Most residential installations are completed in a single day.
Assessment & Measurement
We measure your ceiling area, assess your roof space access points and identify any existing insulation that may need to be removed or supplemented.
Compliance Check
We confirm the correct Isotherm thickness required to meet SANS 10400-XA for your climate zone — ensuring your installation is both effective and code-compliant.
Prepare Access
We access the ceiling space via existing hatch points. Where necessary, we carefully lift roof tiles to install insulation in areas with limited access.
Lay Insulation Batts
Isotherm batts are laid between ceiling joists with no gaps, overlaps correctly managed and all light fittings, electrical boxes and downlights properly treated to prevent fire risk.
Edge Sealing
Perimeter edges are sealed to prevent air bypass — a common cause of reduced insulation performance in poorly installed systems.
Clean-Up & Certification
We clean the work area, restore all access points and issue an installation certificate confirming the product installed, thickness and R-value achieved.
Full-Service Insulation,
Combined with Any Roof Job
As a full-service roofing contractor, we install Isotherm insulation as part of a comprehensive roof system — often combined with roof repairs, waterproofing or ceiling replacement in a single, cost-effective project. Every installation comes with a compliance certificate confirming the product, thickness and R-value achieved.
"Me and my wife can't explain how grateful we are to have met Ruan and his team at RR Roof Waterproofing. They are amazing people with the absolute best service I've ever experienced. Our home was under water and within 2 days everything was fixed and not a single leak was found. Thank you RR Roof Waterproofing."
Frequently Asked Questions About Isotherm Insulation
Isotherm is a South African-made ceiling and roof insulation product manufactured from recycled PET plastic bottles. It is non-toxic, non-irritant, fire-retardant and moisture-resistant. Unlike fibreglass or mineral wool, it contains no glass fibres or formaldehyde — making it safe for homes with children, elderly occupants and allergy sufferers.
Properly installed ceiling insulation typically reduces heating and cooling costs by 20–40% depending on your home's construction, the insulation thickness and your usage patterns. In Gauteng's climate — with cold winters and hot summers — most homeowners recover the full installation cost within 2–4 years through energy savings.
Yes. Isotherm products meet the requirements of SANS 10400-XA — the South African National Standard for energy efficiency in buildings. We install the correct thickness for your climate zone and provide an installation certificate confirming compliance. This is particularly important for new builds requiring a Section 10 energy certificate.
Yes. Isotherm can be installed in existing homes through ceiling hatches or by carefully lifting roof tiles to access areas without hatch points. No major construction or ceiling removal is required for a standard installation. Our team works cleanly and restores all access points on completion.
Most residential ceiling insulation installations are completed within a single day. Larger homes or commercial buildings may require 2–3 days. If the installation is being done as part of a combined roof repair or ceiling replacement project, we will schedule the work in the correct sequence and provide an overall timeline in your quotation.