Cornerstone Insulating Render
Render, Insulation and Dehumidifier all in one.
Insulating Render has been specifically designed to reduce heat loss in solid walls and older buildings. Working as a lightweight base coat for rendering and plastering applications, Insulating Render offers significantly improved insulation and moisture management, as well as much faster application times compared to conventional lime renders.
- Work Quicker, Apply Thicker – Insulating Render can be applied up to 30mm depth as a single coat, compared to standard lime mortar which is 15mm per coat, significantly reducing labour times and costs.
- Let Your Walls Breathe – behaves the same as a standard NHL2 render, offering a highly vapour permeable and highly flexible coating, helping reduce issues such as damp and decay
- Highly Insulating - with a measured K Value of 0.12, a 25mm coat will improve the U Value of a solid wall by around 40%, whereas a 50mm coat will improve the U Value by around 60%.
- A Dehumidifier for Your Walls – by incorporating non-porous aggregate Insulating Render helps to regulate moisture movement through the wall and reduce cold spots. Independent testing verifies how Insulating Render can absorb, store and buffer excess moisture, releasing it when suitable and never trapping it within the wall, improving the air quality and comfort of internal spaces.
- Superior Performance - Insulating Render is at least 50% more insulating than the closest performing market alternative and is priced to meet or cost less than market alternatives.
- Space Is A Premium – Insulating Render can be applied directly the wall it does not require framing or boards which can reduce space. If you are looking to maximise insulation it can also be incorporated within a boarded system.
- Natural Mineral Ingredients – made using only NHL2, recycled aggregates and additives enabling it to be used on virtually any background and contains no organic content so no fear of the coating rotting or breaking down.
Lightweight render which offers low strength, high flexibility, high vapour permeability and advanced thermal performance, for use on solid walled masonry.
Cornerstone Insulating Render is designed to improve the thermal performance of solid walled masonry, whilst maintaining the high vapour permeability and low strength of an NHL2 render. Insulating Render offers a viable solution for Part L1B legislation in that it meets the requirements for improving the thermal performance of a wall, whilst maintaining a permeable fabric which absorbs and readily allows for the evaporation of moisture and will not prejudice the character of the host building or increase the risk of long-term deterioration of the building fabric or fittings. With a measured K Value of 0.12, Insulating Render significantly outperforms similar systems both in terms of performance and cost. A 50mm application will improve the U value of a solid wall by 50% or more, significantly reducing heat loss.
Most available lightweight/insulating materials use aggregates that have a two-dimensional structure, when these are subject to pressure during application the aggregate can breakdown, reducing both the thermal performance and durability of the mortar. Cornerstone Insulating Render uses a specialist recycled ultra-lightweight hardened aggregate with a three-dimensional structure, which does not breakdown under application and improves both the durability and insulating properties of the render.
Fibre additions improve the flexural strength of the render, distributing stresses across the render to help reduce point loading, and negate the need for any mesh to be applied to the wall or inserted within the render
Insulating Render can also be used in sustainable construction projects as a basecoat onto natural building materials such as hemp, straw and rammed earth. The insulating properties help reduce the thermal expansion differentials between the background and any subsequent coatings.
For internal applications it can be applied as backing coat or through to finish coat, or finished with a lime plaster. For external applications, apply as a backing coat with Cornerstone NHL2 Drymix as a finish.
Suitable for application onto most host surfaces.
If working on weak/friable backgrounds such as cob, please contact us for further application information.
After mixing, a bag will produce approximately 13.8 litres of mortar.
For quantity purposes, assume that for every 10mm depth, you would need 0.72 bags per square meter.
- Quality controlled production.
- Consistency of mix ratio and working additions.
- Significantly reduces heat loss in solid masonry.
- Meets the requirements of Building Regulation Part L1B.
- Lightweight material, can be applied up to 25mm per coat.
- Uses recycled aggregate and NHL2, making a low carbon render.
- Significantly reduced risk of shrinkage.
- Improved durability.
- Non-porous aggregate, reducing cold bridging and damp spots.
- Improved and even cure which offers an improved bond with the substrate.
- Extended working and finishing time.
- Helps reduce the thermal expansion differentials between the background and any subsequent coatings.
- Fibre additions improve the flexural strength, distributing stresses and reduces point loading.
Area of Use
Internally on properties with solid wall construction.
Used In Conjunction With
Insulating Render can be used as a base coat, for internal plaster like finishes we would advise using Cornish Lime CLM66 fine putty plaster and for external finer finishes we would recommend using CLD35 Drymix fine render.
In general, this will be determined by the purpose and application of the mortar. We would expect appropriate preparation in accordance with best practice; where the surface is clean, free of dust and
Where necessary the background should be adequately dampened to promote adhesion/bond with the host surface. Dense impervious backgrounds/materials are unlikely to be very absorbent and require little to no dampening, whereas more absorbent backgrounds/materials require adequate dampening in order to prevent rapid drying. Whilst Cornerstone Insulating Render includes additions to try and mitigate these issues, best practice still needs to be followed.
A bag of Cornerstone Insulating Render will require 4 to 5 litres of clean potable water. The water addition will vary according to the application and desired consistency/workability of the mortar. Always avoid making the mortar too wet, as this can promote shrinkage issues, especially when used as a render.
For drum type mixers, it is essential not to overfill the mixer. As a dry mixed material, it is possible that some settlement or separation may occur in the bag during transit; when mixing part bags, it is especially important that the dry contents are thoroughly blended prior to mixing with water.
Best Practice/Advised Mixing - First add 60 to 70% water of the total water into the mixer, followed by the Cornerstone Insulating Render and turn the mixer on. Allow the mortar to mix until the water is thoroughly distributed, then add additional water to achieve desired consistency.
Mix for a minimum of 5 minutes.
Other mix methods - We accept that it is generally site practice to add the water to the mortar, providing the mortar is well mixed and not too wet, this method will be sufficient.
Quenching - Like most lime mortars Cornerstone Insulating Render will benefit from Quenching; allow the mortar to stand for 10 to 20 minutes after mixing, before use.
Should additional water be needed after quenching to maintain workability, this can be added and mixed thoroughly through the mortar.
Once water has been added, Cornerstone Insulating Render has an open time of at least 18 hours.
Each project is unique, always seek professional advice before undertaking a project.