Insulating render / plaster

听Insulating Render/Plaster.听

Climate Change Mitigation Retrofit Advancing Net Zero Solutions Operational energy

Problem Addressed

How to increase the thermal efficiency of walls and floors in older buildings without adversely affecting moisture levels.

Solution Overview

When used as a simple insulating base coat on walls or as a lightweight screed on floors,听ProofTherm听adds significantly enhanced thermal performance to what are essentially functional elements of a building and provides a simple and affordable insulation upgrade for hard-to-treat properties or areas within a property. This improvement on standard plasters, renders and screeds reduces heat loss through floors and walls and thereby reduces the carbon footprint of older buildings.听

ProofTherm uses expanded Perlite as an insulating aggregate.听Perlite is a naturally occurring form of volcanic glass that is full of minute air bubbles trapped in a honeycomb-like structure. When incorporated into their bagged, ready to use render, plaster and screed range it is these microscopic air bubbles that create an effective barrier to thermal conductivity. 听

ProofTherm听insulating render has an independently verified thermal conductivity of 0.06w/m2K. When applied as a render basecoat to an external/internal wall it creates a breathable, thermally resistant continuous barrier against heat loss, reducing the heating/cooling load of the building without creating the moisture retention problems so often associated with the regular petrochemical insulating materials.听

A 20mm base coat of听ProofTherm听render to a bare masonry wall can increase its thermal resistance by up to 250%.听

The material cost of using听ProofTherm听insulating render is approximately 拢6.50 ex vat per m2 when applied at 20mm depth. Heat loss through walls accounts for approximately听a third of all heat loss in the average UK home according to the . Once installed, ProofTherm听requires zero maintenance and has a service life in excess of 30 years.听

Company name

ProofShield

UK availability

Yes

Solution launch date

2019

Case Study

ProofTherm听was used to insulate the external walls of a Victorian property in听London听in October 2020. By February 2021 the owner had measured a 20% reduction in relative humidity in the lower ground floor area as the breathable nature of听ProofTherm听allowed the bricks to dry out once the existing sand and cement render was removed.听听听

听As the lower ground floor area was electrically heated and metered independently from the rest of the property, a recorded reduction in electricity use of 22% across the equivalent period听and with the same occupation and usage patterns can be largely attributed to the increased insulation values of the walls.听

0.06 w/m2K

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