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Internal and external wood fibre insulation boards – Diffutherm

Diffutherm wood fibre insulation boards are:-

  • used in external insulation and internal insulation systems.
  • the original, renderable, wet-process wood fibre insulation board, used for over 30 years.
  • breathable, eco friendly and used on flat solid walls and timber frames.
  • the best and most simple way to insulate low energy homes, including Passivhaus homes.
  • used inside and outside as part of our solid wall insulation systems.
  • great for keeping you warm in the winter and cool in the summer.

Prices: from £24.03 + VAT per board

Internal and external wood fibre insulation boards – Diffutherm

Diffutherm wood fibre insulation boards are:-

  • used in external insulation and internal insulation systems.
  • the original, renderable, wet-process wood fibre insulation board, used for over 30 years.
  • breathable, eco friendly and used on flat solid walls and timber frames.
  • the best and most simple way to insulate low energy homes, including Passivhaus homes.
  • used inside and outside as part of our solid wall insulation systems.
  • great for keeping you warm in the winter and cool in the summer.

Prices: from £24.03 + VAT per board

Close-ups.

Take a closer look at this product with these additional images.

Image description: This shows the edge profile of the Diffutherm boards and how the render that is applied to the surface is built up. This system is used externally on timber frame and masonry buildings.

Image description: This image shows the profile of the Unger-Diffutherm boards which form part of the UdiIN internal insulation system. 

“Diffutherm is one of the most time tested renderable wood fibre boards. It is versatile, easy to use and durable” – Chris Brookman

 

Product overview.

Where is it used?

  • The Unger-Diffutherm wood fibre boards can be used for internal (UdiIN) and external (UdiFRONT) solid wall insulation on brick or stone (a levelling coat of render may be required if the surface is uneven) or for direct fixing to timber frames to form a breathable and durable insulation system.

How much will you need?

  • Each Unger-Diffutherm Insulation board is 1290 x 780mm which is 1.0m².
  • Allow of 5-10% for waste depending on the complexity of the walls.
  • If you’re not sure which board you need please contact us.

What is their thermal conductivity?

  • The Diffutherm boards have a conductivity of 0.046 W/mK and a density of 230kg/m³.

How is it used?

  • In short, by screwing it to the wall and rendering it. Simple.
  • For the full video installation guide please click here or read through the quick summary below.
  • Wall surfaces need to be flat and smooth so there aren’t any voids behind the boards once installed.
  • Diffutherm boards should not be installed less than 300mm above the ground level with either plinth insulation coming up to this point or a plinth rail to start the system off.
  • Ideally there should be no horizontal or vertical joints within 300mm of the corners of any openings. If there are then the system adhesive must be used to glue the joints.
  • Diffutherm boards should be laid in horizontal rows, with the tongues pointing upward and firmly fixed with the system fixings using an average of 9/m² externally or 6/m² internally.
  • We’ve got junction detail drawings and loads more info on our product information page and installation videos in our resources section.

Product overview.

Where is it used?

  • The Unger-Diffutherm wood fibre boards can be used for internal (UdiIN) and external (UdiFRONT) solid wall insulation on brick or stone (a levelling coat of render may be required if the surface is uneven) or for direct fixing to timber frames to form a breathable and durable insulation system.

How is it used?

  • In short, by screwing it to the wall and rendering it. Simple.
  • For the full video installation guide please click here or read through the quick summary below.
  • Wall surfaces need to be flat and smooth so there aren’t any voids behind the boards once installed.
  • Diffutherm boards should not be installed less than 300mm above the ground level with either plinth insulation coming up to this point or a plinth rail to start the system off.
  • Ideally there should be no horizontal or vertical joints within 300mm of the corners of any openings. If there are then the system adhesive must be used to glue the joints.
  • Diffutherm boards should be laid in horizontal rows, with the tongues pointing upward and firmly fixed with the system fixings using an average of 9/m² externally or 6/m² internally.
  • We’ve got junction detail drawings and loads more info on our product information page.

How much will you need?

  • Each Unger-Diffutherm Insulation board is 1290 x 780mm which is 1.0m².
  • Allow of 5-10% for waste depending on the complexity of the walls.
  • If you’re not sure which board you need please contact us.

How much will you need?

  • Each Unger-Diffutherm Insulation board is 1290 x 780mm which is 1.0m².
  • Allow of 5-10% for waste depending on the complexity of the walls.
  • If you’re not sure which board you need please contact us.

What is their thermal conductivity?

  • The Diffutherm boards have a conductivity of 0.043 W/mK and a density of 210kg/m³.

Material in action.

Here you can see the Unger-Diffutherm boards being used in the UdiIN system inside an old stone cottage. Unusually the walls were very flat so no levelling coat plaster was required prior to installation.

These boards were then coated in the UdiMULTIGRUND vapour regulating plaster and the surface was finished with the Baumit Klima Glatte fine lime skimming plaster.

Prices & Shipping

Here you will find pricing and shipping estimates. To get a fixed quote, please call our technical team on 01392 861763 or get in touch via the form below.

The Unger Diffutherm boards are priced as below:-

Thickness [mm] Weight [kg/sqm] Board dim. [mm] Number of Boards per pallet Pallet covers [sqm] Per pallet [kg]  single board cost board cost in full pallets
60 9.6 1275 x 765, 0.975m² 30 29.25 300 £26.70 £24.03
80 12.8 1275 x 765, 0.975m² 22 21.45 300 £34.57 £31.11
100 16 1275 x 765, 0.975m² 18 17.55 300 £43.03 £38.72
120 19.2 1275 x 765, 0.975m² 15 14.625 300 £47.90 £43.11

Carriage is typically calculated at £70 + VAT per pallet and all orders will be sent on a pallet. This price does vary if delivery is required to remote locations. If you require only a few boards we may be able to get slightly cheaper shipping so please contact us for a more accurate price.

Request an estimate.

In summary, if you are looking for more than just a builders’ merchant, we might be the guys to talk to.

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Request an estimate.

In summary, if you are looking for more than just a builders’ merchant, we might be the guys to talk to.

  • This field is for validation purposes and should be left unchanged.

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Overview

Back to Earth is a natural building material supplier. We're not your typical builders'​ merchant though and instead work closely with our clients during the planning, designing and building phases of projects.

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