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PolyWall - Cavity Wall Insulation Boards

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Order PolyWall Cavity Wall Insulation Directly Online Today!

The Cost Effective Way To Insulate Your Exterior Cavity Walls In South Africa

Store Prices:

Current Retail Prices Per m2 (Excl. VAT):

  • There are too many variations to document the per m2 for each thickness and region.
  • That said, it is very easy to calculate the per m2 rate. Just divide the board price by 3!
  • You will find that this is an extremely cost effective product for this application.

PolyWall - Cavity Wall Insulation Boards

PolyWall Insulation, also known a cavity wall insulation is a very cost effective way to insulate cavity walls.

PolyWall Insulation is an expanded polystyrene insulation board that is expanded to sufficient densities for this application unlike other extruded polystyrene options that are manufactured by default at much higher densities. The higher the density the higher the effective cost.

  • Cavity Wall Insulation is the insulation layer that is placed between the inner and outer brick layers of the outer perimeter walls of a building.

  • This insulation layer significantly reduces the transfer of heat and cold through the external perimeter walls of buildings.

  • In summer the sun-facing exterior walls get hot and this heat is kept out of the living space by the cavity wall insulation.

  • In winter this cavity wall insulation keeps the cold out.

  • When heating and cooling systems are used to keep regulate temperatures, cavity wall insulation significantly reduces the energy consumption of such HVAC systems.

SANS 10400 Part XA Building Requirements For Buildings:

Cavity Wall Insulation is a building requirement, in terms of the SANS 10400 Part XA Building Regulations.

The building code states that in residential developments a minimum thermal R-values of 1 should be achieved. This is achieved by installing a PolyWall Insulation board of minimum thickness 35mm.

Obviously the thicker the PolyWall Boards the greater the thermal insulation. In residential and commercial buildings 40mm, 50mm & 75mm boards are most commonly specified.

PolyWall Insulation For Cold Rooms:

PolyWall Insulation is used extensively in commercial cold & freezer room floor applications. Here the thicknesses can vary from 150mm to 300mm depending on the thermal insulation R-Value Requirement.

You will need to consult with your architect to determine exactly what thickness you need for your specific requirement.

PolyWall Thicknesses & Thermal Insulation R-Values:

Board Thickness Thermal Insulation (R-Value)
35mm 1.000 (Recommended)
40mm 1.143 (Recommended)
50mm 1.429 (Recommended)
75mm 2.145
100mm 2.857
120mm 3.429
150mm 4.286
200mm 5.714
300mm 8.571

PolyWall Densities & Compressive Strength:

PolyWall Insulation is sold in a Medium Density because there is no compressive strength requirement in this application. This is a very significant cost saving point when it comes to choosing between this product and other extruded polystyrene offerings.

Manufacture & Supply:

All our polystyrene sheets & blocks are manufactured locally in South Africa and distributed nationally from our regional factories in:

  • Johannesburg
  • Cape Town
  • Durban
  • East London
  • Port Elizabeth

We also export our polystyrene sheets, blocks and other products to certain countries in Africa, based on order volumes.

How Many Sheets Do I Need?

  • Simply divide the total insulation area by 3 to get the number of sheets
  • Then add a few for wastage.

Order Process:

  • Add the products and quantities you want to you order.
  • Select delivery or request a delivery quote if your location is not covered.
  • Submit your order for review
  • We will then call you to review your order or discuss delivery costs with you.
  • You will then approve the order or not.
  • We will then cut your order and deliver it.
  • Fast & Easy!

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We Can Advise & Help You Find The Best Products & Prices On All The Major - Floor, Wall, Ceiling & Concrete Roof Insulations Applications & Products In South Africa.

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VAT Number: 4220273447

CO. Reg Number: 2016/072709/07

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011 678 5626


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